diff --git a/applications/solvers/electromagnetics/mhdFoam/createPhiB.H b/applications/solvers/electromagnetics/mhdFoam/createPhiB.H
index 02b48f8d28..967c98f55b 100644
--- a/applications/solvers/electromagnetics/mhdFoam/createPhiB.H
+++ b/applications/solvers/electromagnetics/mhdFoam/createPhiB.H
@@ -1,4 +1,4 @@
-IOobject phiBHeader
+typeIOobject<surfaceScalarField> phiBHeader
 (
     "phiB",
     runTime.timeName(),
@@ -9,7 +9,7 @@ IOobject phiBHeader
 
 surfaceScalarField* phiBPtr = nullptr;
 
-if (phiBHeader.typeHeaderOk<surfaceScalarField>(true))
+if (phiBHeader.headerOk())
 {
     Info<< "Reading face flux ";
 
diff --git a/applications/solvers/lagrangian/particleFoam/createFields.H b/applications/solvers/lagrangian/particleFoam/createFields.H
index 7039378a86..2dfff06109 100644
--- a/applications/solvers/lagrangian/particleFoam/createFields.H
+++ b/applications/solvers/lagrangian/particleFoam/createFields.H
@@ -56,7 +56,7 @@ volScalarField mu
 Info<< "Constructing clouds" << endl;
 parcelCloudList clouds(rhoInf, U, mu, g);
 
-IOobject Hheader
+typeIOobject<volVectorField> Hheader
 (
     "H",
     runTime.timeName(),
@@ -67,14 +67,14 @@ IOobject Hheader
 
 autoPtr<volVectorField> HPtr;
 
-if (Hheader.typeHeaderOk<volVectorField>(true))
+if (Hheader.headerOk())
 {
     Info<< "\nReading field H\n" << endl;
 
     HPtr.reset(new volVectorField (Hheader, mesh));
 }
 
-IOobject HdotGradHheader
+typeIOobject<volVectorField> HdotGradHheader
 (
     "HdotGradH",
     runTime.timeName(),
@@ -85,7 +85,7 @@ IOobject HdotGradHheader
 
 autoPtr<volVectorField> HdotGradHPtr;
 
-if (HdotGradHheader.typeHeaderOk<volVectorField>(true))
+if (HdotGradHheader.headerOk())
 {
     Info<< "Reading field HdotGradH" << endl;
 
diff --git a/applications/solvers/lagrangian/particleFoam/createNonInertialFrameFields.H b/applications/solvers/lagrangian/particleFoam/createNonInertialFrameFields.H
index 731a8196da..6ca6c7afe5 100644
--- a/applications/solvers/lagrangian/particleFoam/createNonInertialFrameFields.H
+++ b/applications/solvers/lagrangian/particleFoam/createNonInertialFrameFields.H
@@ -1,6 +1,6 @@
     Info<< "Reading non-inertial frame fields" << endl;
 
-    IOobject linearAccelerationHeader
+    typeIOobject<uniformDimensionedVectorField> linearAccelerationHeader
     (
         "linearAcceleration",
         runTime.timeName(),
@@ -11,13 +11,7 @@
 
     autoPtr<uniformDimensionedVectorField> linearAccelerationPtr;
 
-    if
-    (
-        linearAccelerationHeader.typeHeaderOk<uniformDimensionedVectorField>
-        (
-            true
-        )
-    )
+    if (linearAccelerationHeader.headerOk())
     {
         Info<< "    Reading " << linearAccelerationHeader.name() << endl;
 
@@ -28,7 +22,7 @@
     }
 
 
-    IOobject angularVelocityHeader
+    typeIOobject<uniformDimensionedVectorField> angularVelocityHeader
     (
         "angularVelocity",
         runTime.timeName(),
@@ -39,7 +33,7 @@
 
     autoPtr<uniformDimensionedVectorField> angularVelocityPtr;
 
-    if (angularVelocityHeader.typeHeaderOk<uniformDimensionedVectorField>(true))
+    if (angularVelocityHeader.headerOk())
     {
         Info<< "    Reading " << angularVelocityHeader.name() << endl;
 
@@ -50,7 +44,7 @@
     }
 
 
-    IOobject angularAccelerationHeader
+    typeIOobject<uniformDimensionedVectorField> angularAccelerationHeader
     (
         "angularAcceleration",
         runTime.timeName(),
@@ -61,13 +55,7 @@
 
     autoPtr<uniformDimensionedVectorField> angularAccelerationPtr;
 
-    if
-    (
-        angularAccelerationHeader.typeHeaderOk<uniformDimensionedVectorField>
-        (
-            true
-        )
-    )
+    if (angularAccelerationHeader.headerOk())
     {
         Info<< "    Reading " << angularAccelerationHeader.name() << endl;
 
@@ -78,7 +66,7 @@
     }
 
 
-    IOobject centreOfRotationHeader
+    typeIOobject<uniformDimensionedVectorField> centreOfRotationHeader
     (
         "centreOfRotation",
         runTime.timeName(),
@@ -89,13 +77,7 @@
 
     autoPtr<uniformDimensionedVectorField> centreOfRotationPtr;
 
-    if
-    (
-        centreOfRotationHeader.typeHeaderOk<uniformDimensionedVectorField>
-        (
-            true
-        )
-    )
+    if (centreOfRotationHeader.headerOk())
     {
         Info<< "    Reading " << centreOfRotationHeader.name() << endl;
 
diff --git a/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C b/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
index 36d768e2ee..5bb4e4d0f1 100644
--- a/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
+++ b/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
@@ -46,7 +46,7 @@ Foam::IOobject Foam::twoPhaseChangeModel::createIOobject
     const compressibleTwoPhaseMixture& mixture
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         phaseChangePropertiesName,
         mixture.alpha1().mesh().time().constant(),
@@ -55,7 +55,7 @@ Foam::IOobject Foam::twoPhaseChangeModel::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         io.readOpt() = IOobject::MUST_READ_IF_MODIFIED;
         return io;
diff --git a/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C b/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
index 27bf5ffe45..f7384ef5c0 100644
--- a/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
+++ b/applications/solvers/multiphase/compressibleInterFoam/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
@@ -32,7 +32,7 @@ Foam::autoPtr<Foam::twoPhaseChangeModel> Foam::twoPhaseChangeModel::New
     const compressibleTwoPhaseMixture& mixture
 )
 {
-    IOobject twoPhaseChangeModelIO
+    typeIOobject<IOdictionary> twoPhaseChangeModelIO
     (
         IOobject
         (
@@ -47,7 +47,7 @@ Foam::autoPtr<Foam::twoPhaseChangeModel> Foam::twoPhaseChangeModel::New
 
     word modelType(twoPhaseChangeModels::noPhaseChange::typeName);
 
-    if (twoPhaseChangeModelIO.typeHeaderOk<IOdictionary>(false))
+    if (twoPhaseChangeModelIO.headerOk())
     {
         IOdictionary(twoPhaseChangeModelIO).lookup
         (
diff --git a/applications/solvers/multiphase/multiphaseEulerFoam/phaseSystems/phaseModel/MovingPhaseModel/MovingPhaseModel.C b/applications/solvers/multiphase/multiphaseEulerFoam/phaseSystems/phaseModel/MovingPhaseModel/MovingPhaseModel.C
index 12ebd0b7df..aa79f834bc 100644
--- a/applications/solvers/multiphase/multiphaseEulerFoam/phaseSystems/phaseModel/MovingPhaseModel/MovingPhaseModel.C
+++ b/applications/solvers/multiphase/multiphaseEulerFoam/phaseSystems/phaseModel/MovingPhaseModel/MovingPhaseModel.C
@@ -44,7 +44,7 @@ Foam::MovingPhaseModel<BasePhaseModel>::phi(const volVectorField& U) const
 {
     word phiName(IOobject::groupName("phi", this->name()));
 
-    IOobject phiHeader
+    typeIOobject<surfaceScalarField> phiHeader
     (
         phiName,
         U.mesh().time().timeName(),
@@ -52,7 +52,7 @@ Foam::MovingPhaseModel<BasePhaseModel>::phi(const volVectorField& U) const
         IOobject::NO_READ
     );
 
-    if (phiHeader.typeHeaderOk<surfaceScalarField>(true))
+    if (phiHeader.headerOk())
     {
         Info<< "Reading face flux field " << phiName << endl;
 
diff --git a/applications/utilities/mesh/advanced/autoRefineMesh/autoRefineMesh.C b/applications/utilities/mesh/advanced/autoRefineMesh/autoRefineMesh.C
index 58f812b34b..b46ba36b87 100644
--- a/applications/utilities/mesh/advanced/autoRefineMesh/autoRefineMesh.C
+++ b/applications/utilities/mesh/advanced/autoRefineMesh/autoRefineMesh.C
@@ -639,7 +639,7 @@ int main(int argc, char *argv[])
 
     Info<< "Checking for motionProperties\n" << endl;
 
-    IOobject motionObj
+    typeIOobject<IOdictionary> motionObj
     (
         "motionProperties",
         runTime.constant(),
@@ -651,7 +651,7 @@ int main(int argc, char *argv[])
     // corrector for mesh motion
     twoDPointCorrector* correct2DPtr = nullptr;
 
-    if (motionObj.typeHeaderOk<IOdictionary>(true))
+    if (motionObj.headerOk())
     {
         Info<< "Reading " << runTime.constant() / "motionProperties"
             << endl << endl;
diff --git a/applications/utilities/mesh/advanced/refinementLevel/refinementLevel.C b/applications/utilities/mesh/advanced/refinementLevel/refinementLevel.C
index de8fe12cb4..2a4deec137 100644
--- a/applications/utilities/mesh/advanced/refinementLevel/refinementLevel.C
+++ b/applications/utilities/mesh/advanced/refinementLevel/refinementLevel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -230,7 +230,7 @@ int main(int argc, char *argv[])
 
 
     // Refinement level
-    IOobject refHeader
+    typeIOobject<labelIOList> refHeader
     (
         "refinementLevel",
         runTime.timeName(),
@@ -238,7 +238,7 @@ int main(int argc, char *argv[])
         runTime
     );
 
-    if (!readLevel && refHeader.typeHeaderOk<labelIOList>(true))
+    if (!readLevel && refHeader.headerOk())
     {
         WarningInFunction
             << "Detected " << refHeader.name() << " file in "
diff --git a/applications/utilities/mesh/advanced/selectCells/edgeStats.C b/applications/utilities/mesh/advanced/selectCells/edgeStats.C
index 35427309da..284714dc45 100644
--- a/applications/utilities/mesh/advanced/selectCells/edgeStats.C
+++ b/applications/utilities/mesh/advanced/selectCells/edgeStats.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -74,7 +74,7 @@ Foam::edgeStats::edgeStats(const polyMesh& mesh)
     mesh_(mesh),
     normalDir_(3)
 {
-    IOobject motionObj
+    typeIOobject<IOdictionary> motionObj
     (
         "motionProperties",
         mesh.time().constant(),
@@ -83,7 +83,7 @@ Foam::edgeStats::edgeStats(const polyMesh& mesh)
         IOobject::NO_WRITE
     );
 
-    if (motionObj.typeHeaderOk<IOdictionary>(true))
+    if (motionObj.headerOk())
     {
         Info<< "Reading " << mesh.time().constant() / "motionProperties"
             << endl << endl;
diff --git a/applications/utilities/mesh/conversion/foamToStarMesh/getTimeIndex.H b/applications/utilities/mesh/conversion/foamToStarMesh/getTimeIndex.H
index bcfd41ec99..f9f10d2edb 100644
--- a/applications/utilities/mesh/conversion/foamToStarMesh/getTimeIndex.H
+++ b/applications/utilities/mesh/conversion/foamToStarMesh/getTimeIndex.H
@@ -8,7 +8,7 @@
      && runTime.timeName() != "0"
     )
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "time",
             runTime.timeName(),
@@ -19,7 +19,7 @@
             false
         );
 
-        if (io.typeHeaderOk<IOdictionary>(true))
+        if (io.headerOk())
         {
             IOdictionary timeObject
             (
diff --git a/applications/utilities/mesh/conversion/foamToSurface/getTimeIndex.H b/applications/utilities/mesh/conversion/foamToSurface/getTimeIndex.H
index 22b31b514c..5ba1650b6c 100644
--- a/applications/utilities/mesh/conversion/foamToSurface/getTimeIndex.H
+++ b/applications/utilities/mesh/conversion/foamToSurface/getTimeIndex.H
@@ -8,7 +8,7 @@
      && runTime.timeName() != "0"
     )
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "time",
             runTime.timeName(),
@@ -19,7 +19,7 @@
             false
         );
 
-        if (io.typeHeaderOk<IOdictionary>(true))
+        if (io.headerOk())
         {
             IOdictionary timeObject
             (
diff --git a/applications/utilities/mesh/generation/blockMesh/blockMesh.C b/applications/utilities/mesh/generation/blockMesh/blockMesh.C
index 195030cd2e..b5014c8eae 100644
--- a/applications/utilities/mesh/generation/blockMesh/blockMesh.C
+++ b/applications/utilities/mesh/generation/blockMesh/blockMesh.C
@@ -149,9 +149,12 @@ int main(int argc, char *argv[])
         }
     }
 
-    IOobject meshDictIO(systemDictIO(dictName, args, runTime, regionName));
+    typeIOobject<IOdictionary> meshDictIO
+    (
+        systemDictIO(dictName, args, runTime, regionName)
+    );
 
-    if (!meshDictIO.typeHeaderOk<IOdictionary>(true))
+    if (!meshDictIO.headerOk())
     {
         FatalErrorInFunction
             << "Cannot find file " << meshDictIO.relativeObjectPath()
diff --git a/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C b/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
index dc1060c05a..1aaf2d7e34 100644
--- a/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
+++ b/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
@@ -84,7 +84,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
 {
     // Create dummy system/fv*
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSchemes",
             mesh.time().system(),
@@ -95,9 +95,9 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
             false
         );
 
-        Info<< "Testing:" << io.objectPath<IOdictionary>() << endl;
+        Info<< "Testing:" << io.objectPath() << endl;
 
-        if (!io.typeHeaderOk<IOdictionary>(false))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
@@ -112,7 +112,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
         }
     }
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSolution",
             mesh.time().system(),
@@ -123,7 +123,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
             false
         );
 
-        if (!io.typeHeaderOk<IOdictionary>(false))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
diff --git a/applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C b/applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C
index 2d2d252a6a..0e644fba5c 100644
--- a/applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C
+++ b/applications/utilities/mesh/generation/extrude/extrudeToRegionMesh/extrudeToRegionMesh.C
@@ -342,7 +342,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
 {
     // Create dummy system/fv*
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSchemes",
             mesh.time().system(),
@@ -353,9 +353,9 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
             false
         );
 
-        Info<< "Testing:" << io.objectPath<IOdictionary>() << endl;
+        Info<< "Testing:" << io.objectPath() << endl;
 
-        if (!io.typeHeaderOk<IOdictionary>(true))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
@@ -370,7 +370,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
         }
     }
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSolution",
             mesh.time().system(),
@@ -381,7 +381,7 @@ void createDummyFvMeshFiles(const polyMesh& mesh, const word& regionName)
             false
         );
 
-        if (!io.typeHeaderOk<IOdictionary>(true))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
@@ -2492,7 +2492,7 @@ int main(int argc, char *argv[])
     {
         autoPtr<pointIOField> patchFaceCentresPtr;
 
-        IOobject io
+        typeIOobject<pointIOField> io
         (
             "patchFaceCentres",
             mesh.pointsInstance(),
@@ -2500,7 +2500,8 @@ int main(int argc, char *argv[])
             mesh,
             IOobject::MUST_READ
         );
-        if (io.typeHeaderOk<pointIOField>(true))
+
+        if (io.headerOk())
         {
             // Read patchFaceCentres and patchEdgeCentres
             Info<< "Reading patch face,edge centres : "
diff --git a/applications/utilities/mesh/manipulation/deformedGeom/deformedGeom.C b/applications/utilities/mesh/manipulation/deformedGeom/deformedGeom.C
index 508c76aade..6b4a3995d4 100644
--- a/applications/utilities/mesh/manipulation/deformedGeom/deformedGeom.C
+++ b/applications/utilities/mesh/manipulation/deformedGeom/deformedGeom.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -65,7 +65,7 @@ int main(int argc, char *argv[])
 
         Info<< "Time = " << runTime.timeName() << endl;
 
-        IOobject Uheader
+        typeIOobject<volVectorField> Uheader
         (
             "U",
             runTime.timeName(),
@@ -74,7 +74,7 @@ int main(int argc, char *argv[])
         );
 
         // Check U exists
-        if (Uheader.typeHeaderOk<volVectorField>(true))
+        if (Uheader.headerOk())
         {
             Info<< "    Reading U" << endl;
             volVectorField U(Uheader, mesh);
diff --git a/applications/utilities/mesh/manipulation/refineMesh/refineMesh.C b/applications/utilities/mesh/manipulation/refineMesh/refineMesh.C
index a03afc206a..24b25675eb 100644
--- a/applications/utilities/mesh/manipulation/refineMesh/refineMesh.C
+++ b/applications/utilities/mesh/manipulation/refineMesh/refineMesh.C
@@ -189,11 +189,11 @@ int main(int argc, char *argv[])
 
     // Dictionary to control refinement
     const word dictName("refineMeshDict");
-    IOobject dictIO(systemDictIO(dictName, args, runTime));
+    typeIOobject<IOdictionary> dictIO(systemDictIO(dictName, args, runTime));
     dictionary refineDict;
     if (readDict)
     {
-        if (dictIO.typeHeaderOk<IOdictionary>(true))
+        if (dictIO.headerOk())
         {
             Info<< "Refining according to "
                 << dictIO.path(typeGlobalFile<IOdictionary>()) << nl << endl;
@@ -209,7 +209,7 @@ int main(int argc, char *argv[])
     }
     else if (!refineAllCells)
     {
-        if (dictIO.typeHeaderOk<IOdictionary>(true))
+        if (dictIO.headerOk())
         {
             Info<< "Refining according to "
                 << dictIO.path(typeGlobalFile<IOdictionary>()) << nl << endl;
diff --git a/applications/utilities/mesh/manipulation/splitMeshRegions/splitMeshRegions.C b/applications/utilities/mesh/manipulation/splitMeshRegions/splitMeshRegions.C
index 8a0b855962..6f6c29f9c5 100644
--- a/applications/utilities/mesh/manipulation/splitMeshRegions/splitMeshRegions.C
+++ b/applications/utilities/mesh/manipulation/splitMeshRegions/splitMeshRegions.C
@@ -575,7 +575,7 @@ autoPtr<mapPolyMesh> createRegionMesh
 {
     // Create dummy system/fv*
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSchemes",
             mesh.time().system(),
@@ -586,9 +586,9 @@ autoPtr<mapPolyMesh> createRegionMesh
             false
         );
 
-        Info<< "Testing:" << io.objectPath<IOdictionary>() << endl;
+        Info<< "Testing:" << io.objectPath() << endl;
 
-        if (!io.typeHeaderOk<IOdictionary>(true))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
@@ -603,7 +603,7 @@ autoPtr<mapPolyMesh> createRegionMesh
         }
     }
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "fvSolution",
             mesh.time().system(),
@@ -614,8 +614,7 @@ autoPtr<mapPolyMesh> createRegionMesh
             false
         );
 
-        if (!io.typeHeaderOk<IOdictionary>(true))
-        // if (!exists(io.objectPath()))
+        if (!io.headerOk())
         {
             Info<< "Writing dummy " << regionName/io.name() << endl;
             dictionary dummyDict;
diff --git a/applications/utilities/mesh/manipulation/topoSet/Make/options b/applications/utilities/mesh/manipulation/topoSet/Make/options
index 54c035b8f5..b90bc48df7 100644
--- a/applications/utilities/mesh/manipulation/topoSet/Make/options
+++ b/applications/utilities/mesh/manipulation/topoSet/Make/options
@@ -2,4 +2,5 @@ EXE_INC = \
     -I$(LIB_SRC)/meshTools/lnInclude
 
 EXE_LIBS = \
+    -lfiniteVolume \
     -lmeshTools
diff --git a/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C b/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
index 14f89c3fd0..055249d662 100644
--- a/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
+++ b/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
@@ -89,7 +89,7 @@ bool writeZones(const word& name, const fileName& meshDir, Time& runTime)
 
     bool writeOk = false;
 
-    if (io.typeHeaderOk<meshCellZones>(false))
+    if (io.headerOk())
     {
         Info<< "        Reading " << io.headerClassName()
             << " : " << name << endl;
@@ -199,7 +199,7 @@ bool writeOptionalMeshObject
 
     bool writeOk = false;
 
-    bool haveFile = io.typeHeaderOk<IOField<label>>(false);
+    bool haveFile = io.headerOk();
 
     // Make sure all know if there is a valid class name
     stringList classNames(1, io.headerClassName());
diff --git a/applications/utilities/miscellaneous/foamFormatConvert/writeMeshObject.H b/applications/utilities/miscellaneous/foamFormatConvert/writeMeshObject.H
index 18d2098b38..dc35152135 100644
--- a/applications/utilities/miscellaneous/foamFormatConvert/writeMeshObject.H
+++ b/applications/utilities/miscellaneous/foamFormatConvert/writeMeshObject.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -48,7 +48,7 @@ inline bool writeMeshObject
     bool disableHeaderChecking = false
 )
 {
-    IOobject io
+    typeIOobject<CheckType> io
     (
         name,
         runTime.timeName(),
@@ -61,11 +61,7 @@ inline bool writeMeshObject
 
     bool writeOk = false;
 
-    if
-    (
-        io.typeHeaderOk<Type>(false)
-     && io.headerClassName() == CheckType::typeName
-    )
+    if (io.headerOk())
     {
         Info<< "        Reading " << io.headerClassName()
             << " : " << name << endl;
diff --git a/applications/utilities/miscellaneous/patchSummary/patchSummary.C b/applications/utilities/miscellaneous/patchSummary/patchSummary.C
index a0d424aade..8788cb1982 100644
--- a/applications/utilities/miscellaneous/patchSummary/patchSummary.C
+++ b/applications/utilities/miscellaneous/patchSummary/patchSummary.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -106,7 +106,7 @@ int main(int argc, char *argv[])
                 IOobject::MUST_READ
             );
 
-            if (obj.typeHeaderOk<volScalarField>(false))
+            if (obj.headerOk())
             {
                 addToFieldList(vsf, obj, objI, mesh);
                 addToFieldList(vvf, obj, objI, mesh);
diff --git a/applications/utilities/parallelProcessing/decomposePar/decomposePar.C b/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
index 22c0883f28..c23c05a043 100644
--- a/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
+++ b/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
@@ -382,7 +382,7 @@ int main(int argc, char *argv[])
         label nProcs = fileHandler().nProcs(runTime.path(), regionDir);
 
         // Get the dictionary IO
-        const IOobject dictIO
+        const typeIOobject<IOdictionary> dictIO
         (
             systemDictIO(dictName, args, runTime, regionName)
         );
@@ -432,13 +432,13 @@ int main(int argc, char *argv[])
                 IOobject::NO_WRITE,
                 false
             ),
-            dictIO.objectPath<domainDecomposition>()
+            dictIO.objectPath()
         );
 
         // Decompose the mesh
         if (!decomposeFieldsOnly)
         {
-            mesh.decomposeMesh(dictIO.objectPath<domainDecomposition>());
+            mesh.decomposeMesh(dictIO.objectPath());
 
             mesh.writeDecomposition(decomposeSets);
 
diff --git a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
index a56541a3bd..a41c52eaa4 100644
--- a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
+++ b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
@@ -331,9 +331,8 @@ int main(int argc, char *argv[])
 
 
             // Problem: faceCompactIOList recognises both 'faceList' and
-            //          'faceCompactList' so we should be lenient when doing
-            //          typeHeaderOk
-            if (!facesIO.typeHeaderOk<faceCompactIOList>(false))
+            //          'faceCompactList' so we cannot check the type
+            if (!facesIO.headerOk())
             {
                 Info<< "No mesh." << nl << endl;
                 continue;
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkData.H b/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkData.H
index 47a3540da7..76b55aada7 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkData.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkData.H
@@ -16,6 +16,6 @@ for (label n1=0; n1<Times.size() && variableGood; ++n1)
             Times[n1].name(),
             mesh,
             IOobject::NO_READ
-        ).typeHeaderOk<volScalarField>(false);
+        ).headerOk();
     }
 }
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkMeshMoving.H b/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkMeshMoving.H
index d4027ad1c5..a0b096e328 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkMeshMoving.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/checkMeshMoving.H
@@ -9,7 +9,7 @@ if (Times.size() > 1)
     {
         if (Times[timeI].name() != mesh.pointsInstance())
         {
-            IOobject io
+            typeIOobject<pointIOField> io
             (
                 "points",
                 Times[timeI].name(),
@@ -17,7 +17,8 @@ if (Times.size() > 1)
                 mesh,
                 IOobject::NO_READ
             );
-            if (io.typeHeaderOk<pointIOField>(true))
+
+            if (io.headerOk())
             {
                 meshMoving = true;
                 break;
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C b/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
index 0958680bff..14326151ba 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -584,10 +584,8 @@ int main(int argc, char *argv[])
                     IOobject::MUST_READ
                 );
 
-                bool fieldExists = fieldObject.typeHeaderOk<IOField<scalar>>
-                (
-                    false
-                );
+                bool fieldExists = fieldObject.headerOk();
+
                 if (fieldType == scalarIOField::typeName)
                 {
                     ensightCloudField<scalar>
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/checkHasMovingMesh.H b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/checkHasMovingMesh.H
index 454cb3ebb6..00a3f283b3 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/checkHasMovingMesh.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/checkHasMovingMesh.H
@@ -6,13 +6,13 @@ if (timeDirs.size() > 1)
     hasMovingMesh = true;
     for (label i=0; i < timeDirs.size() && hasMovingMesh; ++i)
     {
-        hasMovingMesh = IOobject
+        hasMovingMesh = typeIOobject<pointIOField>
         (
             "points",
             timeDirs[i].name(),
             polyMesh::meshSubDir,
             mesh,
             IOobject::NO_READ
-        ).typeHeaderOk<pointIOField>(true);
+        ).headerOk();
     }
 }
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/getTimeIndex.H b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/getTimeIndex.H
index 12d7674501..553d7140fc 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/getTimeIndex.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/getTimeIndex.H
@@ -13,7 +13,7 @@
      && runTime.timeName() != "0"
     )
     {
-        IOobject io
+        typeIOobject<IOdictionary> io
         (
             "time",
             runTime.timeName(),
@@ -24,7 +24,7 @@
             false
         );
 
-        if (io.typeHeaderOk<IOdictionary>(true))
+        if (io.headerOk())
         {
             io.readOpt() = IOobject::MUST_READ_IF_MODIFIED;
             IOdictionary timeObject(io);
@@ -34,7 +34,7 @@
         else
         {
             Info<< "skip ... missing entry "
-                << io.objectPath<IOdictionary>() << endl;
+                << io.objectPath() << endl;
             continue;
         }
     }
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/moveMesh.H b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/moveMesh.H
index f894e2c136..c92d52603a 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/moveMesh.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsightParts/moveMesh.H
@@ -1,5 +1,5 @@
 {
-    IOobject io
+    typeIOobject<pointIOField> io
     (
         "points",
         runTime.timeName(),
@@ -7,7 +7,7 @@
         mesh
     );
 
-    if (io.typeHeaderOk<pointIOField>(true))
+    if (io.headerOk())
     {
         // Read new points
         io.readOpt() = IOobject::MUST_READ;
diff --git a/applications/utilities/postProcessing/dataConversion/foamToGMV/gmvOutput.H b/applications/utilities/postProcessing/dataConversion/foamToGMV/gmvOutput.H
index 03a76e5856..4c65e583e3 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToGMV/gmvOutput.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToGMV/gmvOutput.H
@@ -71,13 +71,7 @@ for (label i=0; i < nTypes; i++)
             IOobject::NO_READ
         );
 
-        if
-        (
-            lagrangianHeader.typeHeaderOk<IOPosition<Cloud<passiveParticle>>>
-            (
-                false
-            )
-        )
+        if (lagrangianHeader.headerOk())
         {
             Cloud<passiveParticle> particles(mesh, cloud::defaultName);
 
diff --git a/applications/utilities/postProcessing/dataConversion/foamToGMV/moveMesh.H b/applications/utilities/postProcessing/dataConversion/foamToGMV/moveMesh.H
index c1a1f8dee7..c85f55efaa 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToGMV/moveMesh.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToGMV/moveMesh.H
@@ -1,4 +1,4 @@
-IOobject ioPoints
+typeIOobject<pointIOField> ioPoints
 (
     "points",
     runTime.timeName(),
@@ -6,7 +6,7 @@ IOobject ioPoints
     mesh
 );
 
-if (ioPoints.typeHeaderOk<pointIOField>(true))
+if (ioPoints.headerOk())
 {
     Info<< "new points available" << endl;
     // Reading new points
diff --git a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoam.C b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoam.C
index bf30c483cc..3f285ff716 100644
--- a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoam.C
+++ b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoam.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -586,13 +586,13 @@ double* Foam::vtkPVFoam::findTimes(int& nTimeSteps)
 
             if
             (
-                IOobject
+                typeIOobject<pointIOField>
                 (
                     "points",
                     timeName,
                     meshDir_,
                     runTime
-                ).typeHeaderOk<pointIOField>(true)
+                ).headerOk()
             )
             {
                 break;
diff --git a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamFields.C b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamFields.C
index a6344fc67d..8a2ffa30a2 100644
--- a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamFields.C
+++ b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamFields.C
@@ -120,7 +120,7 @@ void Foam::vtkPVFoam::convertFields(vtkMultiBlockDataSet* output)
         forAllConstIter(IOobjectList, objects, iter)
         {
             Info<< "  " << iter()->name()
-                << " == " << iter()->objectPath<volScalarField>() << nl;
+                << " == " << iter()->objectPath(false) << nl;
         }
         printMemory();
     }
diff --git a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamUpdateInfo.C b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamUpdateInfo.C
index 70891352a0..73a764db06 100644
--- a/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamUpdateInfo.C
+++ b/applications/utilities/postProcessing/graphics/PVReaders/vtkPVFoam/vtkPVFoamUpdateInfo.C
@@ -124,7 +124,7 @@ Foam::wordList Foam::vtkPVFoam::getZoneNames(const word& zoneType) const
         false
     );
 
-    if (ioObj.typeHeaderOk<meshCellZones>(false))
+    if (ioObj.headerOk())
     {
         zonesEntries zones(ioObj);
 
@@ -321,7 +321,7 @@ void Foam::vtkPVFoam::updateInfoPatches
     {
         // Mesh not loaded - read from file
         // but this could fail if we've supplied a bad region name
-        IOobject ioObj
+        typeIOobject<polyBoundaryMesh> ioObj
         (
             "boundary",
             dbPtr_().findInstance
@@ -338,7 +338,7 @@ void Foam::vtkPVFoam::updateInfoPatches
         );
 
         // This should only ever fail if the mesh region doesn't exist
-        if (ioObj.typeHeaderOk<polyBoundaryMesh>(true))
+        if (ioObj.headerOk())
         {
             polyBoundaryMeshEntries patchEntries(ioObj);
 
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/USERD_set_filenames.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/USERD_set_filenames.H
index 164602e22d..0da7ed1e0d 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/USERD_set_filenames.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/USERD_set_filenames.H
@@ -171,7 +171,7 @@ int USERD_set_filenames
         false
     );
 
-    if (sprayHeader.typeHeaderOk<Cloud<passiveParticle>>(false))
+    if (sprayHeader.headerOk())
     {
         Info<< "[Found lagrangian]" << endl;
 
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldScalar.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldScalar.H
index 518b53bb18..2beba1f74f 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldScalar.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldScalar.H
@@ -1,10 +1,9 @@
-
 if (nVar >= Num_variables - nSprayVariables)
 {
     return Z_UNDEF;
 }
 
-IOobject fieldObjectPtr
+typeIOobject<volScalarField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -12,7 +11,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volScalarField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldTensor.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldTensor.H
index f8b45ec83c..19bb27f5e4 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldTensor.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldTensor.H
@@ -4,7 +4,7 @@ if (nVar >= Num_variables - nSprayVariables)
 }
 
 
-IOobject fieldObjectPtr
+typeIOobject<volTensorField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -12,7 +12,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volTensorField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldVector.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldVector.H
index ec94dbf460..d5652d2518 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldVector.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getFieldVector.H
@@ -4,7 +4,7 @@ if (nVar >= Num_variables - nSprayVariables)
 }
 
 
-IOobject fieldObjectPtr
+typeIOobject<volVectorField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -12,7 +12,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volVectorField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldScalar.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldScalar.H
index 549a80f64f..b1325d9757 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldScalar.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldScalar.H
@@ -5,7 +5,7 @@ if (nVar >= Num_variables - nSprayVariables)
     return Z_UNDEF;
 }
 
-IOobject fieldObjectPtr
+typeIOobject<volScalarField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -13,7 +13,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volScalarField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldTensor.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldTensor.H
index 0aed2ac26e..b9954689fb 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldTensor.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldTensor.H
@@ -5,7 +5,7 @@ if (nVar >= Num_variables - nSprayVariables)
     return Z_UNDEF;
 }
 
-IOobject fieldObjectPtr
+typeIOobject<volTensorField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -13,7 +13,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volTensorField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldVector.H b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldVector.H
index 4c6fe3832f..6a8f139955 100644
--- a/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldVector.H
+++ b/applications/utilities/postProcessing/graphics/ensightFoamReader/getPatchFieldVector.H
@@ -5,7 +5,7 @@ if (nVar >= Num_variables - nSprayVariables)
     return Z_UNDEF;
 }
 
-IOobject fieldObjectPtr
+typeIOobject<volVectorField> fieldObjectPtr
 (
     fieldNames[var2field[nVar]],
     runTime.timeName(),
@@ -13,7 +13,7 @@ IOobject fieldObjectPtr
     IOobject::NO_READ
 );
 
-if (!fieldObjectPtr.typeHeaderOk<volVectorField>(true))
+if (!fieldObjectPtr.headerOk())
 {
     return Z_UNDEF;
 }
diff --git a/applications/utilities/postProcessing/miscellaneous/postChannel/readFields.H b/applications/utilities/postProcessing/miscellaneous/postChannel/readFields.H
index 83a7c12046..b257d73645 100644
--- a/applications/utilities/postProcessing/miscellaneous/postChannel/readFields.H
+++ b/applications/utilities/postProcessing/miscellaneous/postChannel/readFields.H
@@ -1,4 +1,4 @@
-    IOobject UMeanHeader
+    typeIOobject<volVectorField> UMeanHeader
     (
         "UMean",
         runTime.timeName(),
@@ -6,7 +6,7 @@
         IOobject::MUST_READ
     );
 
-    if (!UMeanHeader.typeHeaderOk<volVectorField>(true))
+    if (!UMeanHeader.headerOk())
     {
         Info<< "    No UMean field" << endl;
         continue;
diff --git a/applications/utilities/preProcessing/applyBoundaryLayer/applyBoundaryLayer.C b/applications/utilities/preProcessing/applyBoundaryLayer/applyBoundaryLayer.C
index 467317e5c3..1bc77c5567 100644
--- a/applications/utilities/preProcessing/applyBoundaryLayer/applyBoundaryLayer.C
+++ b/applications/utilities/preProcessing/applyBoundaryLayer/applyBoundaryLayer.C
@@ -174,7 +174,7 @@ int main(int argc, char *argv[])
         epsilon.write();
 
         // Turbulence omega
-        IOobject omegaHeader
+        typeIOobject<volScalarField> omegaHeader
         (
             "omega",
             runTime.timeName(),
@@ -184,7 +184,7 @@ int main(int argc, char *argv[])
             false
         );
 
-        if (omegaHeader.typeHeaderOk<volScalarField>(true))
+        if (omegaHeader.headerOk())
         {
             volScalarField omega(omegaHeader, mesh);
 
@@ -202,7 +202,7 @@ int main(int argc, char *argv[])
         }
 
         // Turbulence nuTilda
-        IOobject nuTildaHeader
+        typeIOobject<volScalarField> nuTildaHeader
         (
             "nuTilda",
             runTime.timeName(),
@@ -212,7 +212,7 @@ int main(int argc, char *argv[])
             false
         );
 
-        if (nuTildaHeader.typeHeaderOk<volScalarField>(true))
+        if (nuTildaHeader.headerOk())
         {
             volScalarField nuTilda(nuTildaHeader, mesh);
             nuTilda = nut;
diff --git a/applications/utilities/preProcessing/mapFields/Make/options b/applications/utilities/preProcessing/mapFields/Make/options
index 7bd964094e..579fec7157 100644
--- a/applications/utilities/preProcessing/mapFields/Make/options
+++ b/applications/utilities/preProcessing/mapFields/Make/options
@@ -1,4 +1,4 @@
-EXE_INC = \
+EXE_INC = -ggdb3 \
     -I$(LIB_SRC)/meshTools/lnInclude \
     -I$(LIB_SRC)/lagrangian/basic/lnInclude \
     -I$(LIB_SRC)/finiteVolume/lnInclude \
diff --git a/applications/utilities/preProcessing/mapFields/MapConsistentVolFields.H b/applications/utilities/preProcessing/mapFields/MapConsistentVolFields.H
index 922027b677..8dcaffa00f 100644
--- a/applications/utilities/preProcessing/mapFields/MapConsistentVolFields.H
+++ b/applications/utilities/preProcessing/mapFields/MapConsistentVolFields.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -59,7 +59,7 @@ void MapConsistentVolFields
         // Read field
         fieldType fieldSource(*fieldIter(), meshSource);
 
-        IOobject fieldTargetIOobject
+        typeIOobject<fieldType> fieldTargetIOobject
         (
             fieldIter()->name(),
             meshTarget.time().timeName(),
@@ -68,7 +68,7 @@ void MapConsistentVolFields
             IOobject::AUTO_WRITE
         );
 
-        if (fieldTargetIOobject.typeHeaderOk<fieldType>(true))
+        if (fieldTargetIOobject.headerOk())
         {
             // Read fieldTarget
             fieldType fieldTarget
diff --git a/applications/utilities/preProcessing/mapFields/MapVolFields.H b/applications/utilities/preProcessing/mapFields/MapVolFields.H
index 1e74a3e483..a570b36faa 100644
--- a/applications/utilities/preProcessing/mapFields/MapVolFields.H
+++ b/applications/utilities/preProcessing/mapFields/MapVolFields.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -53,7 +53,7 @@ void MapVolFields
 
     forAllIter(IOobjectList, fields, fieldIter)
     {
-        IOobject fieldTargetIOobject
+        typeIOobject<fieldType> fieldTargetIOobject
         (
             fieldIter()->name(),
             meshTarget.time().timeName(),
@@ -62,7 +62,7 @@ void MapVolFields
             IOobject::AUTO_WRITE
         );
 
-        if (fieldTargetIOobject.typeHeaderOk<fieldType>(true))
+        if (fieldTargetIOobject.headerOk())
         {
             Info<< "    interpolating " << fieldIter()->name() << endl;
 
diff --git a/applications/utilities/preProcessing/mapFields/UnMapped.H b/applications/utilities/preProcessing/mapFields/UnMapped.H
index 5b92eb6562..7357060be5 100644
--- a/applications/utilities/preProcessing/mapFields/UnMapped.H
+++ b/applications/utilities/preProcessing/mapFields/UnMapped.H
@@ -41,7 +41,7 @@ void UnMapped(const IOobjectList& objects)
 
     forAllConstIter(IOobjectList, fields, fieldIter)
     {
-        mvBak(fieldIter()->objectPath<Type>(), "unmapped");
+        mvBak(fieldIter()->objectPath(false), "unmapped");
     }
 }
 
diff --git a/applications/utilities/preProcessing/mapFieldsPar/MapVolFields.H b/applications/utilities/preProcessing/mapFieldsPar/MapVolFields.H
index d8fb072627..fae37a73a3 100644
--- a/applications/utilities/preProcessing/mapFieldsPar/MapVolFields.H
+++ b/applications/utilities/preProcessing/mapFieldsPar/MapVolFields.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -141,7 +141,7 @@ void MapVolFields
         {
             const fieldType fieldSource(*fieldIter(), meshSource);
 
-            IOobject targetIO
+            typeIOobject<fieldType> targetIO
             (
                 fieldName,
                 meshTarget.time().timeName(),
@@ -149,7 +149,7 @@ void MapVolFields
                 IOobject::MUST_READ
             );
 
-            if (targetIO.typeHeaderOk<fieldType>(true))
+            if (targetIO.headerOk())
             {
                 Info<< "    interpolating onto existing field "
                     << fieldName << endl;
diff --git a/applications/utilities/preProcessing/mapFieldsPar/UnMapped.H b/applications/utilities/preProcessing/mapFieldsPar/UnMapped.H
index 5b92eb6562..7357060be5 100644
--- a/applications/utilities/preProcessing/mapFieldsPar/UnMapped.H
+++ b/applications/utilities/preProcessing/mapFieldsPar/UnMapped.H
@@ -41,7 +41,7 @@ void UnMapped(const IOobjectList& objects)
 
     forAllConstIter(IOobjectList, fields, fieldIter)
     {
-        mvBak(fieldIter()->objectPath<Type>(), "unmapped");
+        mvBak(fieldIter()->objectPath(false), "unmapped");
     }
 }
 
diff --git a/applications/utilities/preProcessing/setFields/setFields.C b/applications/utilities/preProcessing/setFields/setFields.C
index 2f3f6992aa..6f91d0c1ff 100644
--- a/applications/utilities/preProcessing/setFields/setFields.C
+++ b/applications/utilities/preProcessing/setFields/setFields.C
@@ -58,7 +58,7 @@ bool setCellFieldType
     word fieldName(fieldValueStream);
 
     // Check the current time directory
-    IOobject fieldHeader
+    typeIOobject<fieldType> fieldHeader
     (
         fieldName,
         mesh.time().timeName(),
@@ -67,9 +67,9 @@ bool setCellFieldType
     );
 
     // Check the "constant" directory
-    if (!fieldHeader.typeHeaderOk<fieldType>(true))
+    if (!fieldHeader.headerOk())
     {
-        fieldHeader = IOobject
+        fieldHeader = typeIOobject<fieldType>
         (
             fieldName,
             mesh.time().constant(),
@@ -79,7 +79,7 @@ bool setCellFieldType
     }
 
     // Check field exists
-    if (fieldHeader.typeHeaderOk<fieldType>(true))
+    if (fieldHeader.headerOk())
     {
         Info<< "    Setting internal values of "
             << fieldHeader.headerClassName()
@@ -204,7 +204,7 @@ bool setFaceFieldType
     word fieldName(fieldValueStream);
 
     // Check the current time directory
-    IOobject fieldHeader
+    typeIOobject<fieldType> fieldHeader
     (
         fieldName,
         mesh.time().timeName(),
@@ -213,9 +213,9 @@ bool setFaceFieldType
     );
 
     // Check the "constant" directory
-    if (!fieldHeader.typeHeaderOk<fieldType>(true))
+    if (!fieldHeader.headerOk())
     {
-        fieldHeader = IOobject
+        fieldHeader = typeIOobject<fieldType>
         (
             fieldName,
             mesh.time().constant(),
@@ -225,7 +225,7 @@ bool setFaceFieldType
     }
 
     // Check field exists
-    if (fieldHeader.typeHeaderOk<fieldType>(true))
+    if (fieldHeader.headerOk())
     {
         Info<< "    Setting patchField values of "
             << fieldHeader.headerClassName()
diff --git a/applications/utilities/surface/surfaceRedistributePar/surfaceRedistributePar.C b/applications/utilities/surface/surfaceRedistributePar/surfaceRedistributePar.C
index 4ba1d85088..cd94c5deda 100644
--- a/applications/utilities/surface/surfaceRedistributePar/surfaceRedistributePar.C
+++ b/applications/utilities/surface/surfaceRedistributePar/surfaceRedistributePar.C
@@ -156,7 +156,7 @@ int main(int argc, char *argv[])
         Pstream::scatterList(meshBb);
     }
 
-    IOobject io
+    typeIOobject<searchableSurface> io
     (
         surfFileName,
         runTime.constant(),
@@ -167,7 +167,7 @@ int main(int argc, char *argv[])
     );
 
     // Look for file (using searchableSurface rules)
-    const fileName actualPath(typeFilePath<searchableSurface>(io));
+    const fileName actualPath(io.filePath());
     fileName localPath(actualPath);
     localPath.replace(runTime.rootPath() + '/', "");
 
diff --git a/src/MomentumTransportModels/momentumTransportModels/laminar/Maxwell/Maxwell.C b/src/MomentumTransportModels/momentumTransportModels/laminar/Maxwell/Maxwell.C
index 631bde75ed..f766efb810 100644
--- a/src/MomentumTransportModels/momentumTransportModels/laminar/Maxwell/Maxwell.C
+++ b/src/MomentumTransportModels/momentumTransportModels/laminar/Maxwell/Maxwell.C
@@ -159,7 +159,7 @@ Maxwell<BasicMomentumTransportModel>::Maxwell
 
         forAll(sigmas_, modei)
         {
-            IOobject header
+            typeIOobject<volSymmTensorField> header
             (
                 IOobject::groupName("sigma" + name(modei), alphaRhoPhi.group()),
                 this->runTime_.timeName(),
@@ -168,7 +168,7 @@ Maxwell<BasicMomentumTransportModel>::Maxwell
             );
 
             // Check if mode field exists and can be read
-            if (header.typeHeaderOk<volSymmTensorField>(true))
+            if (header.headerOk())
             {
                 Info<< "    Reading mode stress field "
                     << header.name() << endl;
diff --git a/src/MomentumTransportModels/momentumTransportModels/momentumTransportModel.C b/src/MomentumTransportModels/momentumTransportModels/momentumTransportModel.C
index 744ad74fc4..e9b853fdcb 100644
--- a/src/MomentumTransportModels/momentumTransportModels/momentumTransportModel.C
+++ b/src/MomentumTransportModels/momentumTransportModels/momentumTransportModel.C
@@ -45,7 +45,7 @@ Foam::IOdictionary Foam::momentumTransportModel::readModelDict
     bool registerObject
 )
 {
-    IOobject momentumTransport
+    typeIOobject<IOdictionary> momentumTransport
     (
         IOobject::groupName(typeName, group),
         obr.time().constant(),
@@ -55,13 +55,13 @@ Foam::IOdictionary Foam::momentumTransportModel::readModelDict
         registerObject
     );
 
-    if (momentumTransport.typeHeaderOk<IOdictionary>(true))
+    if (momentumTransport.headerOk())
     {
         return momentumTransport;
     }
     else
     {
-        IOobject turbulenceProperties
+        typeIOobject<IOdictionary> turbulenceProperties
         (
             IOobject::groupName("turbulenceProperties", group),
             obr.time().constant(),
@@ -71,7 +71,7 @@ Foam::IOdictionary Foam::momentumTransportModel::readModelDict
             registerObject
         );
 
-        if (turbulenceProperties.typeHeaderOk<IOdictionary>(true))
+        if (turbulenceProperties.headerOk())
         {
             return turbulenceProperties;
         }
diff --git a/src/OpenFOAM/db/IOobject/IOobject.H b/src/OpenFOAM/db/IOobject/IOobject.H
index 0004f8fe54..9768f97deb 100644
--- a/src/OpenFOAM/db/IOobject/IOobject.H
+++ b/src/OpenFOAM/db/IOobject/IOobject.H
@@ -61,6 +61,13 @@ Description
       - \par NO_WRITE
         No automatic write on destruction but can be written explicitly
 
+Class
+    Foam::typeIOobject
+
+Description
+    Templated form of IOobject providing type information for file reading and
+    header type checking.
+
 SourceFiles
     IOobject.C
     IOobjectReadHeader.C
@@ -134,6 +141,7 @@ public:
 
         static const NamedEnum<fileCheckTypes, 4> fileCheckTypesNames;
 
+
 private:
 
     // Private Data
@@ -176,6 +184,11 @@ protected:
         //- Set the object state to bad
         void setBad(const string&);
 
+        //- Read header using typeGlobalFile to find file
+        //  and optionally check the headerClassName against Type
+        template<class Type>
+        bool typeHeaderOk(const bool checkType);
+
 
 public:
 
@@ -411,11 +424,6 @@ public:
                 return path(global)/name();
             }
 
-            //- Return complete path + object name including the processor
-            //  sub-directory for a parallel run if globalFile is false for Type
-            template<class Type>
-            inline fileName objectPath() const;
-
             //- Return the path relative to the case directory
             fileName relativePath() const;
 
@@ -438,10 +446,9 @@ public:
             //- Read header
             bool readHeader(Istream&);
 
-            //- Read header (uses typeFilePath to find file) and check header
-            //  info. Optionally checks headerClassName against type
-            template<class Type>
-            bool typeHeaderOk(const bool checkType = true);
+            //- Read header of local object without type-checking
+            //  Mainly used to create IOobjectLists
+            bool headerOk();
 
             //- Helper: warn that type does not support re-reading
             template<class Type>
@@ -516,19 +523,6 @@ inline bool typeGlobalFile()
     return typeGlobal<Type>();
 }
 
-//- Template function for obtaining filePath
-template<class Type>
-inline fileName typeFilePath(const IOobject& io)
-{
-    return io.filePath(Type::typeName, typeGlobalFile<Type>());
-}
-
-template<class Type>
-inline fileName IOobject::objectPath() const
-{
-    return objectPath(typeGlobalFile<Type>());
-}
-
 inline IOobject unregister(const IOobject& io)
 {
     IOobject uio(io);
@@ -537,6 +531,53 @@ inline IOobject unregister(const IOobject& io)
 }
 
 
+/*---------------------------------------------------------------------------*\
+                         Class typeIOobject Declaration
+\*---------------------------------------------------------------------------*/
+
+template<class Type>
+class typeIOobject
+:
+    public IOobject
+{
+
+public:
+
+    // Constructors
+
+        using IOobject::IOobject;
+
+        typeIOobject(const IOobject& io)
+        :
+            IOobject(io)
+        {}
+
+
+    // Member Functions
+
+        // Reading
+
+            //- Read header (uses typeGlobalFile to find file) and check
+            bool headerOk();
+
+            using IOobject::objectPath;
+
+            //- Return the object path for this Type
+            inline fileName objectPath() const
+            {
+                return objectPath(typeGlobalFile<Type>());
+            }
+
+            using IOobject::filePath;
+
+            //- Return the path for the file for this Type
+            inline fileName filePath() const
+            {
+                return filePath(Type::typeName, typeGlobalFile<Type>());
+            }
+};
+
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 } // End namespace Foam
diff --git a/src/OpenFOAM/db/IOobject/IOobjectReadHeader.C b/src/OpenFOAM/db/IOobject/IOobjectReadHeader.C
index 209d465691..465d2e7272 100644
--- a/src/OpenFOAM/db/IOobject/IOobjectReadHeader.C
+++ b/src/OpenFOAM/db/IOobject/IOobjectReadHeader.C
@@ -28,6 +28,12 @@ License
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
+bool Foam::IOobject::headerOk()
+{
+    return typeHeaderOk<IOobject>(false);
+}
+
+
 bool Foam::IOobject::readHeader(Istream& is)
 {
     if (IOobject::debug)
diff --git a/src/OpenFOAM/db/IOobject/IOobjectTemplates.C b/src/OpenFOAM/db/IOobject/IOobjectTemplates.C
index 658479d010..b997a26151 100644
--- a/src/OpenFOAM/db/IOobject/IOobjectTemplates.C
+++ b/src/OpenFOAM/db/IOobject/IOobjectTemplates.C
@@ -49,7 +49,10 @@ bool Foam::IOobject::typeHeaderOk(const bool checkType)
     // Determine local status
     if (!masterOnly || Pstream::master())
     {
-        const fileName fName(typeFilePath<Type>(*this));
+        const fileName fName
+        (
+            filePath(Type::typeName, typeGlobalFile<Type>())
+        );
 
         ok = fp.readHeader(*this, fName, Type::typeName);
         if (ok && checkType && headerClassName_ != Type::typeName)
@@ -88,4 +91,11 @@ void Foam::IOobject::warnNoRereading() const
 }
 
 
+template<class Type>
+bool Foam::typeIOobject<Type>::headerOk()
+{
+    return typeHeaderOk<Type>(true);
+}
+
+
 // ************************************************************************* //
diff --git a/src/OpenFOAM/db/IOobjectList/IOobjectList.C b/src/OpenFOAM/db/IOobjectList/IOobjectList.C
index c698c1df49..ea64485816 100644
--- a/src/OpenFOAM/db/IOobjectList/IOobjectList.C
+++ b/src/OpenFOAM/db/IOobjectList/IOobjectList.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -26,7 +26,6 @@ License
 #include "IOobjectList.H"
 #include "Time.H"
 #include "OSspecific.H"
-#include "IOList.H"
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
@@ -57,7 +56,6 @@ Foam::IOobjectList::IOobjectList
         newInstance
     );
 
-
     forAll(ObjectNames, i)
     {
         IOobject* objectPtr = new IOobject
@@ -72,7 +70,7 @@ Foam::IOobjectList::IOobjectList
         );
 
         // Use object with local scope
-        if (objectPtr->typeHeaderOk<IOList<label>>(false))
+        if (objectPtr->headerOk())
         {
             insert(ObjectNames[i], objectPtr);
         }
diff --git a/src/OpenFOAM/db/regIOobject/regIOobject.C b/src/OpenFOAM/db/regIOobject/regIOobject.C
index 74c556ff0c..1dfe88a1de 100644
--- a/src/OpenFOAM/db/regIOobject/regIOobject.C
+++ b/src/OpenFOAM/db/regIOobject/regIOobject.C
@@ -421,15 +421,15 @@ Foam::fileName Foam::regIOobject::filePath() const
 
 bool Foam::regIOobject::headerOk()
 {
-    // Note: Should be consistent with IOobject::typeHeaderOk(false)
+    // Note: Should be consistent with typeIOobject<Type>::headerOk()
 
     bool ok = true;
 
-    fileName fName(filePath());
+    const fileName fName(filePath());
 
     ok = Foam::fileHandler().readHeader(*this, fName, type());
 
-    if (!ok && IOobject::debug)
+    if (IOobject::debug && (!ok || headerClassName() != type()))
     {
         IOWarningInFunction(fName)
             << "failed to read header of file " << objectPath()
diff --git a/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C b/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
index 37259eab28..f2410313f3 100644
--- a/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
+++ b/src/OpenFOAM/fields/GeometricFields/GeometricField/GeometricField.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -110,10 +110,7 @@ bool Foam::GeometricField<Type, PatchField, GeoMesh>::readIfPresent()
     else if
     (
         this->readOpt() == IOobject::READ_IF_PRESENT
-     && this->template typeHeaderOk<GeometricField<Type, PatchField, GeoMesh>>
-        (
-            true
-        )
+     && this->headerOk()
     )
     {
         readFields();
@@ -141,7 +138,7 @@ template<class Type, template<class> class PatchField, class GeoMesh>
 bool Foam::GeometricField<Type, PatchField, GeoMesh>::readOldTimeIfPresent()
 {
     // Read the old time field if present
-    IOobject field0
+    typeIOobject<GeometricField<Type, PatchField, GeoMesh>> field0
     (
         this->name()  + "_0",
         this->time().timeName(),
@@ -151,13 +148,7 @@ bool Foam::GeometricField<Type, PatchField, GeoMesh>::readOldTimeIfPresent()
         this->registerObject()
     );
 
-    if
-    (
-        field0.template typeHeaderOk<GeometricField<Type, PatchField, GeoMesh>>
-        (
-            true
-        )
-    )
+    if (field0.headerOk())
     {
         if (debug)
         {
diff --git a/src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.C b/src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.C
index f3a75c7ca7..8b2e57ae51 100644
--- a/src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.C
+++ b/src/OpenFOAM/global/fileOperations/fileOperation/fileOperation.C
@@ -370,9 +370,8 @@ bool Foam::fileOperation::exists(IOobject& io) const
     }
     else
     {
-        ok =
-            isFile(objPath)
-         && io.typeHeaderOk<IOList<label>>(false);// object with local scope
+        // IOobject::headerOk assumes local scope
+        ok = isFile(objPath) && io.headerOk();
     }
 
     if (!ok)
@@ -389,9 +388,8 @@ bool Foam::fileOperation::exists(IOobject& io) const
             }
             else
             {
-                ok =
-                    isFile(originalPath)
-                 && io.typeHeaderOk<IOList<label>>(false);
+                // IOobject::headerOk assumes local scope
+                ok = isFile(originalPath) && io.headerOk();
             }
         }
     }
diff --git a/src/OpenFOAM/meshes/polyMesh/globalMeshData/globalMeshData.C b/src/OpenFOAM/meshes/polyMesh/globalMeshData/globalMeshData.C
index a8903d8317..28ffabfa4d 100644
--- a/src/OpenFOAM/meshes/polyMesh/globalMeshData/globalMeshData.C
+++ b/src/OpenFOAM/meshes/polyMesh/globalMeshData/globalMeshData.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -1858,7 +1858,7 @@ const Foam::labelList& Foam::globalMeshData::sharedPointGlobalLabels() const
         );
         labelList& sharedPointGlobalLabels = sharedPointGlobalLabelsPtr_();
 
-        IOobject addrHeader
+        typeIOobject<labelIOList> addrHeader
         (
             "pointProcAddressing",
             mesh_.facesInstance()/mesh_.meshSubDir,
@@ -1866,7 +1866,7 @@ const Foam::labelList& Foam::globalMeshData::sharedPointGlobalLabels() const
             IOobject::MUST_READ
         );
 
-        if (addrHeader.typeHeaderOk<labelIOList>(true))
+        if (addrHeader.headerOk())
         {
             // There is a pointProcAddressing file so use it to get labels
             // on the original mesh
diff --git a/src/OpenFOAM/meshes/polyMesh/polyMesh.C b/src/OpenFOAM/meshes/polyMesh/polyMesh.C
index c638081595..2337430f95 100644
--- a/src/OpenFOAM/meshes/polyMesh/polyMesh.C
+++ b/src/OpenFOAM/meshes/polyMesh/polyMesh.C
@@ -137,7 +137,7 @@ void Foam::polyMesh::calcDirections() const
 
 Foam::autoPtr<Foam::labelIOList> Foam::polyMesh::readTetBasePtIs() const
 {
-    IOobject io
+    typeIOobject<labelIOList> io
     (
         "tetBasePtIs",
         instance(),
@@ -147,7 +147,7 @@ Foam::autoPtr<Foam::labelIOList> Foam::polyMesh::readTetBasePtIs() const
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<labelIOList>())
+    if (io.headerOk())
     {
         return autoPtr<labelIOList>(new labelIOList(io));
     }
@@ -1250,7 +1250,7 @@ Foam::IOobject Foam::polyMesh::points0IO
     {
         // Check that points0 are actually in constant directory
 
-        IOobject io
+        typeIOobject<pointIOField> io
         (
             "points0",
             instance,
@@ -1261,7 +1261,7 @@ Foam::IOobject Foam::polyMesh::points0IO
             false
         );
 
-        if (io.typeHeaderOk<pointIOField>())
+        if (io.headerOk())
         {
             return io;
         }
diff --git a/src/OpenFOAM/meshes/preservePatchTypes/preservePatchTypes.C b/src/OpenFOAM/meshes/preservePatchTypes/preservePatchTypes.C
index 160c92e6e8..331d7b370e 100644
--- a/src/OpenFOAM/meshes/preservePatchTypes/preservePatchTypes.C
+++ b/src/OpenFOAM/meshes/preservePatchTypes/preservePatchTypes.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -46,7 +46,7 @@ void Foam::preservePatchTypes
 
     // Read boundary file as single dictionary
     {
-        IOobject patchEntriesHeader
+        typeIOobject<polyBoundaryMeshEntries> patchEntriesHeader
         (
             "boundary",
             meshInstance,
@@ -57,7 +57,7 @@ void Foam::preservePatchTypes
             false
         );
 
-        if (patchEntriesHeader.typeHeaderOk<polyBoundaryMesh>(true))
+        if (patchEntriesHeader.headerOk())
         {
             // Create a list of entries from the boundary file.
             polyBoundaryMeshEntries patchEntries(patchEntriesHeader);
diff --git a/src/ThermophysicalTransportModels/laminar/laminarThermophysicalTransportModel/laminarThermophysicalTransportModel.C b/src/ThermophysicalTransportModels/laminar/laminarThermophysicalTransportModel/laminarThermophysicalTransportModel.C
index 154fec2113..14c8508ec3 100644
--- a/src/ThermophysicalTransportModels/laminar/laminarThermophysicalTransportModel/laminarThermophysicalTransportModel.C
+++ b/src/ThermophysicalTransportModels/laminar/laminarThermophysicalTransportModel/laminarThermophysicalTransportModel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2020-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -82,7 +82,7 @@ Foam::laminarThermophysicalTransportModel
     const thermoModel& thermo
 )
 {
-    IOobject header
+    typeIOobject<IOdictionary> header
     (
         IOobject::groupName
         (
@@ -96,7 +96,7 @@ Foam::laminarThermophysicalTransportModel
         false
     );
 
-    if (header.typeHeaderOk<IOdictionary>(true))
+    if (header.headerOk())
     {
         IOdictionary modelDict(header);
 
diff --git a/src/ThermophysicalTransportModels/turbulence/LES/LESThermophysicalTransportModel/LESThermophysicalTransportModel.C b/src/ThermophysicalTransportModels/turbulence/LES/LESThermophysicalTransportModel/LESThermophysicalTransportModel.C
index 8d82ef73d9..e9f7d994fc 100644
--- a/src/ThermophysicalTransportModels/turbulence/LES/LESThermophysicalTransportModel/LESThermophysicalTransportModel.C
+++ b/src/ThermophysicalTransportModels/turbulence/LES/LESThermophysicalTransportModel/LESThermophysicalTransportModel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2020-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -82,7 +82,7 @@ Foam::LESThermophysicalTransportModel
     const thermoModel& thermo
 )
 {
-    IOobject header
+    typeIOobject<IOdictionary> header
     (
         IOobject::groupName
         (
@@ -96,7 +96,7 @@ Foam::LESThermophysicalTransportModel
         false
     );
 
-    if (header.typeHeaderOk<IOdictionary>(true))
+    if (header.headerOk())
     {
         IOdictionary modelDict(header);
 
diff --git a/src/ThermophysicalTransportModels/turbulence/RAS/RASThermophysicalTransportModel/RASThermophysicalTransportModel.C b/src/ThermophysicalTransportModels/turbulence/RAS/RASThermophysicalTransportModel/RASThermophysicalTransportModel.C
index 12f30e60fe..e00596da93 100644
--- a/src/ThermophysicalTransportModels/turbulence/RAS/RASThermophysicalTransportModel/RASThermophysicalTransportModel.C
+++ b/src/ThermophysicalTransportModels/turbulence/RAS/RASThermophysicalTransportModel/RASThermophysicalTransportModel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2020-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -82,7 +82,7 @@ Foam::RASThermophysicalTransportModel
     const thermoModel& thermo
 )
 {
-    IOobject header
+    typeIOobject<IOdictionary> header
     (
         IOobject::groupName
         (
@@ -96,7 +96,7 @@ Foam::RASThermophysicalTransportModel
         false
     );
 
-    if (header.typeHeaderOk<IOdictionary>(true))
+    if (header.headerOk())
     {
         IOdictionary modelDict(header);
 
diff --git a/src/combustionModels/combustionModel/combustionModel.C b/src/combustionModels/combustionModel/combustionModel.C
index 60545c1c19..056ffe4f98 100644
--- a/src/combustionModels/combustionModel/combustionModel.C
+++ b/src/combustionModels/combustionModel/combustionModel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -47,7 +47,7 @@ Foam::IOobject Foam::combustionModel::createIOobject
     const word& combustionProperties
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         thermo.phasePropertyName(combustionProperties),
         thermo.T().mesh().time().constant(),
@@ -56,7 +56,7 @@ Foam::IOobject Foam::combustionModel::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         io.readOpt() = IOobject::MUST_READ_IF_MODIFIED;
         return io;
diff --git a/src/combustionModels/combustionModel/combustionModelNew.C b/src/combustionModels/combustionModel/combustionModelNew.C
index 28f64d8415..526ed49284 100644
--- a/src/combustionModels/combustionModel/combustionModelNew.C
+++ b/src/combustionModels/combustionModel/combustionModelNew.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -35,7 +35,7 @@ Foam::autoPtr<Foam::combustionModel> Foam::combustionModel::New
     const word& combustionProperties
 )
 {
-    IOobject combIO
+    typeIOobject<IOdictionary> combIO
     (
         IOobject
         (
@@ -49,7 +49,7 @@ Foam::autoPtr<Foam::combustionModel> Foam::combustionModel::New
     );
 
     word modelType(combustionModels::noCombustion::typeName);
-    if (combIO.typeHeaderOk<IOdictionary>(false))
+    if (combIO.headerOk())
     {
         IOdictionary(combIO).lookup(combustionModel::typeName) >> modelType;
     }
diff --git a/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C b/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
index fa86056ea4..784f410673 100644
--- a/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
+++ b/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -30,9 +30,9 @@ License
 
 Foam::autoPtr<Foam::dynamicFvMesh> Foam::dynamicFvMesh::New(const IOobject& io)
 {
-    IOobject dictHeader(dynamicMeshDictIOobject(io));
+    typeIOobject<IOdictionary> dictHeader(dynamicMeshDictIOobject(io));
 
-    if (dictHeader.typeHeaderOk<IOdictionary>(true))
+    if (dictHeader.headerOk())
     {
         IOdictionary dict(dictHeader);
 
diff --git a/src/dynamicMesh/motionSolvers/componentDisplacement/componentDisplacementMotionSolver.C b/src/dynamicMesh/motionSolvers/componentDisplacement/componentDisplacementMotionSolver.C
index ee139a34aa..09549824dc 100644
--- a/src/dynamicMesh/motionSolvers/componentDisplacement/componentDisplacementMotionSolver.C
+++ b/src/dynamicMesh/motionSolvers/componentDisplacement/componentDisplacementMotionSolver.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2012-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2012-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -111,19 +111,16 @@ Foam::componentDisplacementMotionSolver::componentDisplacementMotionSolver
             << "Number of points in mesh " << mesh.nPoints()
             << " differs from number of points " << points0_.size()
             << " read from file "
-            <<  typeFilePath<pointIOField>
-                (
-                    IOobject
-                    (
-                        "points",
-                        mesh.time().constant(),
-                        polyMesh::meshSubDir,
-                        mesh,
-                        IOobject::MUST_READ,
-                        IOobject::NO_WRITE,
-                        false
-                    )
-                )
+            << typeIOobject<pointIOField>
+               (
+                   "points",
+                   mesh.time().constant(),
+                   polyMesh::meshSubDir,
+                   mesh,
+                   IOobject::MUST_READ,
+                   IOobject::NO_WRITE,
+                   false
+               ).filePath()
             << exit(FatalError);
     }
 }
diff --git a/src/dynamicMesh/motionSolvers/displacement/points0/points0MotionSolver.C b/src/dynamicMesh/motionSolvers/displacement/points0/points0MotionSolver.C
index 01adf0ced7..311cee53ea 100644
--- a/src/dynamicMesh/motionSolvers/displacement/points0/points0MotionSolver.C
+++ b/src/dynamicMesh/motionSolvers/displacement/points0/points0MotionSolver.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2016-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2016-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -51,19 +51,16 @@ Foam::points0MotionSolver::points0MotionSolver
             << "Number of points in mesh " << mesh.nPoints()
             << " differs from number of points " << points0_.size()
             << " read from file "
-            <<  typeFilePath<pointIOField>
-                (
-                    IOobject
-                    (
-                        "points",
-                        mesh.time().constant(),
-                        polyMesh::meshSubDir,
-                        mesh,
-                        IOobject::MUST_READ,
-                        IOobject::NO_WRITE,
-                        false
-                    )
-                )
+            << typeIOobject<pointIOField>
+               (
+                   "points",
+                   mesh.time().constant(),
+                   polyMesh::meshSubDir,
+                   mesh,
+                   IOobject::MUST_READ,
+                   IOobject::NO_WRITE,
+                   false
+               ).filePath()
             << exit(FatalError);
     }
 }
diff --git a/src/dynamicMesh/pointInterpolator/dynamicMeshPointInterpolator.C b/src/dynamicMesh/pointInterpolator/dynamicMeshPointInterpolator.C
index f77a81d7fc..88f9c6ad81 100644
--- a/src/dynamicMesh/pointInterpolator/dynamicMeshPointInterpolator.C
+++ b/src/dynamicMesh/pointInterpolator/dynamicMeshPointInterpolator.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -52,7 +52,7 @@ Foam::dynamicMeshPointInterpolator::dynamicMeshPointInterpolator
 
     forAll(allTimes, i)
     {
-        IOobject io
+        typeIOobject<pointVectorField> io
         (
             fieldName_,
             allTimes[i].name(),
@@ -61,7 +61,8 @@ Foam::dynamicMeshPointInterpolator::dynamicMeshPointInterpolator
             IOobject::NO_WRITE,
             false
         );
-        if (io.typeHeaderOk<pointVectorField>(false))
+
+        if (io.headerOk())
         {
             names.append(allTimes[i].name());
             values.append(allTimes[i].value());
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
index 983a9afe29..0d5be0102e 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2015-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2015-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -39,11 +39,11 @@ License
 Foam::hexRef8Data::hexRef8Data(const IOobject& io)
 {
     {
-        IOobject rio(io);
+        typeIOobject<labelIOList> rio(io);
         rio.rename("cellLevel");
         bool haveFile = returnReduce
         (
-            rio.typeHeaderOk<labelIOList>(true),
+            rio.headerOk(),
             orOp<bool>()
         );
         if (haveFile)
@@ -53,11 +53,11 @@ Foam::hexRef8Data::hexRef8Data(const IOobject& io)
         }
     }
     {
-        IOobject rio(io);
+        typeIOobject<labelIOList> rio(io);
         rio.rename("pointLevel");
         bool haveFile = returnReduce
         (
-            rio.typeHeaderOk<labelIOList>(true),
+            rio.headerOk(),
             orOp<bool>()
         );
         if (haveFile)
@@ -67,11 +67,11 @@ Foam::hexRef8Data::hexRef8Data(const IOobject& io)
         }
     }
     {
-        IOobject rio(io);
+        typeIOobject<uniformDimensionedScalarField> rio(io);
         rio.rename("level0Edge");
         bool haveFile = returnReduce
         (
-            rio.typeHeaderOk<uniformDimensionedScalarField>(true),
+            rio.headerOk(),
             orOp<bool>()
         );
         if (haveFile)
@@ -81,11 +81,11 @@ Foam::hexRef8Data::hexRef8Data(const IOobject& io)
         }
     }
     {
-        IOobject rio(io);
+        typeIOobject<refinementHistory> rio(io);
         rio.rename("refinementHistory");
         bool haveFile = returnReduce
         (
-            rio.typeHeaderOk<refinementHistory>(true),
+            rio.headerOk(),
             orOp<bool>()
         );
         if (haveFile)
diff --git a/src/finiteVolume/Make/files b/src/finiteVolume/Make/files
index bfe0298e47..9a1b74d2c5 100644
--- a/src/finiteVolume/Make/files
+++ b/src/finiteVolume/Make/files
@@ -470,4 +470,10 @@ fvConstraints = $(general)/fvConstraints
 $(fvConstraints)/fvConstraint.C
 $(fvConstraints)/fvConstraints.C
 
+cellSources = sets/cellSources
+$(cellSources)/fieldToCell/fieldToCell.C
+
+faceSources = sets/faceSources
+$(faceSources)/patchFluxToFace/patchFluxToFace.C
+
 LIB = $(FOAM_LIBBIN)/libfiniteVolume
diff --git a/src/finiteVolume/cfdTools/general/MRF/IOMRFZoneList.C b/src/finiteVolume/cfdTools/general/MRF/IOMRFZoneList.C
index 35c9e0919a..14970e005f 100644
--- a/src/finiteVolume/cfdTools/general/MRF/IOMRFZoneList.C
+++ b/src/finiteVolume/cfdTools/general/MRF/IOMRFZoneList.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2012-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2012-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -34,7 +34,7 @@ Foam::IOobject Foam::IOMRFZoneList::createIOobject
     const fvMesh& mesh
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         "MRFProperties",
         mesh.time().constant(),
@@ -43,7 +43,7 @@ Foam::IOobject Foam::IOMRFZoneList::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         Info<< "Creating MRF zone list from " << io.name() << endl;
 
diff --git a/src/finiteVolume/cfdTools/general/fvConstraints/fvConstraints.C b/src/finiteVolume/cfdTools/general/fvConstraints/fvConstraints.C
index 3cc6dd6c9a..0fddcd59d6 100644
--- a/src/finiteVolume/cfdTools/general/fvConstraints/fvConstraints.C
+++ b/src/finiteVolume/cfdTools/general/fvConstraints/fvConstraints.C
@@ -42,7 +42,7 @@ Foam::IOobject Foam::fvConstraints::createIOobject
     const fvMesh& mesh
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         typeName,
         mesh.time().system(),
@@ -51,7 +51,7 @@ Foam::IOobject Foam::fvConstraints::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         Info<< "Creating fvConstraints from "
             << io.instance()/io.name() << nl
@@ -66,7 +66,7 @@ Foam::IOobject Foam::fvConstraints::createIOobject
         // check if the fvOptions file is in system
         io.rename("fvOptions");
 
-        if (io.typeHeaderOk<IOdictionary>(true))
+        if (io.headerOk())
         {
             Warning
                 << "Creating fvConstraints from "
@@ -82,7 +82,7 @@ Foam::IOobject Foam::fvConstraints::createIOobject
             // check if the fvOptions file is in constant
             io.instance() = mesh.time().constant();
 
-            if (io.typeHeaderOk<IOdictionary>(true))
+            if (io.headerOk())
             {
                 Warning
                     << "Creating fvConstraints from "
diff --git a/src/finiteVolume/cfdTools/general/fvModels/fvModels.C b/src/finiteVolume/cfdTools/general/fvModels/fvModels.C
index 014a5a62e4..5f8d1212d7 100644
--- a/src/finiteVolume/cfdTools/general/fvModels/fvModels.C
+++ b/src/finiteVolume/cfdTools/general/fvModels/fvModels.C
@@ -42,7 +42,7 @@ Foam::IOobject Foam::fvModels::createIOobject
     const fvMesh& mesh
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         typeName,
         mesh.time().constant(),
@@ -51,7 +51,7 @@ Foam::IOobject Foam::fvModels::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         Info<< "Creating fvModels from "
             << io.instance()/io.name() << nl
@@ -66,7 +66,7 @@ Foam::IOobject Foam::fvModels::createIOobject
         // check if the fvOptions file is in constant
         io.rename("fvOptions");
 
-        if (io.typeHeaderOk<IOdictionary>(true))
+        if (io.headerOk())
         {
             Warning
                 << "Creating fvModels from "
@@ -82,7 +82,7 @@ Foam::IOobject Foam::fvModels::createIOobject
             // check if the fvOptions file is in system
             io.instance() = mesh.time().system();
 
-            if (io.typeHeaderOk<IOdictionary>(true))
+            if (io.headerOk())
             {
                 Warning
                     << "Creating fvModels from "
diff --git a/src/finiteVolume/cfdTools/general/include/checkRadiationModel.H b/src/finiteVolume/cfdTools/general/include/checkRadiationModel.H
index 8decaf9bc9..afdf9f52f4 100644
--- a/src/finiteVolume/cfdTools/general/include/checkRadiationModel.H
+++ b/src/finiteVolume/cfdTools/general/include/checkRadiationModel.H
@@ -1,6 +1,6 @@
 if (!mesh.foundObject<IOdictionary>("radiationProperties"))
 {
-    IOobject radiationProperties
+    typeIOobject<IOdictionary> radiationProperties
     (
         "radiationProperties",
         runTime.constant(),
@@ -10,7 +10,7 @@ if (!mesh.foundObject<IOdictionary>("radiationProperties"))
         false
     );
 
-    if (radiationProperties.typeHeaderOk<IOdictionary>(false))
+    if (radiationProperties.headerOk())
     {
         const word modelType
         (
diff --git a/src/finiteVolume/cfdTools/general/porosityModel/porosityModel/IOporosityModelList.C b/src/finiteVolume/cfdTools/general/porosityModel/porosityModel/IOporosityModelList.C
index a873a32828..9699838e8d 100644
--- a/src/finiteVolume/cfdTools/general/porosityModel/porosityModel/IOporosityModelList.C
+++ b/src/finiteVolume/cfdTools/general/porosityModel/porosityModel/IOporosityModelList.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2012-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2012-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -34,7 +34,7 @@ Foam::IOobject Foam::IOporosityModelList::createIOobject
     const fvMesh& mesh
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         "porosityProperties",
         mesh.time().constant(),
@@ -43,7 +43,7 @@ Foam::IOobject Foam::IOporosityModelList::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         Info<< "Creating porosity model list from " << io.name() << nl << endl;
 
diff --git a/src/finiteVolume/finiteVolume/ddtSchemes/CrankNicolsonDdtScheme/CrankNicolsonDdtScheme.C b/src/finiteVolume/finiteVolume/ddtSchemes/CrankNicolsonDdtScheme/CrankNicolsonDdtScheme.C
index 02ed57bad1..b4a0eb78dc 100644
--- a/src/finiteVolume/finiteVolume/ddtSchemes/CrankNicolsonDdtScheme/CrankNicolsonDdtScheme.C
+++ b/src/finiteVolume/finiteVolume/ddtSchemes/CrankNicolsonDdtScheme/CrankNicolsonDdtScheme.C
@@ -120,12 +120,12 @@ CrankNicolsonDdtScheme<Type>::ddt0_
                 runTime.timeIndex() == runTime.startTimeIndex()
              || runTime.timeIndex() == runTime.startTimeIndex() + 1
             )
-         && IOobject
+         && typeIOobject<DDt0Field<GeoField>>
             (
                 name,
                 startTimeName,
                 mesh()
-            ).typeHeaderOk<DDt0Field<GeoField>>()
+            ).headerOk()
         )
         {
             regIOobject::store
diff --git a/src/meshTools/sets/cellSources/fieldToCell/fieldDictionary.H b/src/finiteVolume/sets/cellSources/fieldToCell/fieldDictionary.H
similarity index 97%
rename from src/meshTools/sets/cellSources/fieldToCell/fieldDictionary.H
rename to src/finiteVolume/sets/cellSources/fieldToCell/fieldDictionary.H
index 839e00b381..9001b56806 100644
--- a/src/meshTools/sets/cellSources/fieldToCell/fieldDictionary.H
+++ b/src/finiteVolume/sets/cellSources/fieldToCell/fieldDictionary.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
diff --git a/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C b/src/finiteVolume/sets/cellSources/fieldToCell/fieldToCell.C
similarity index 76%
rename from src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C
rename to src/finiteVolume/sets/cellSources/fieldToCell/fieldToCell.C
index ee6ff3c007..3038e9a641 100644
--- a/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C
+++ b/src/finiteVolume/sets/cellSources/fieldToCell/fieldToCell.C
@@ -29,6 +29,7 @@ License
 #include "Time.H"
 #include "IFstream.H"
 #include "fieldDictionary.H"
+#include "volFields.H"
 #include "addToRunTimeSelectionTable.H"
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
@@ -125,8 +126,7 @@ void Foam::fieldToCell::applyToSet
     topoSet& set
 ) const
 {
-    // Try to load field
-    IOobject fieldObject
+    typeIOobject<volScalarField> fieldObject
     (
         fieldName_,
         mesh().time().timeName(),
@@ -136,41 +136,68 @@ void Foam::fieldToCell::applyToSet
         false
     );
 
-    // Note: should check for volScalarField but that introduces dependency
-    //       on volMesh so just use another type with processor-local scope
-    if (!fieldObject.typeHeaderOk<labelIOList>(false))
+    if (!fieldObject.IOobject::headerOk())
     {
         WarningInFunction
             << "Cannot read field " << fieldName_
             << " from time " << mesh().time().timeName() << endl;
     }
-    else if (fieldObject.headerClassName() == "volScalarField")
+    else if (fieldObject.IOobject::headerOk())
     {
-        IFstream str(typeFilePath<labelIOList>(fieldObject));
+        IFstream str(fieldObject.filePath());
 
         // Read dictionary
-        fieldDictionary fieldDict(fieldObject, fieldObject.headerClassName());
+        const fieldDictionary fieldDict
+        (
+            fieldObject,
+            volScalarField::typeName
+        );
 
-        scalarField internalVals("internalField", fieldDict, mesh().nCells());
+        const scalarField internalVals
+        (
+            "internalField",
+            fieldDict, mesh().nCells()
+        );
 
         applyToSet(action, internalVals, set);
     }
-    else if (fieldObject.headerClassName() == "volVectorField")
-    {
-        IFstream str(typeFilePath<labelIOList>(fieldObject));
-
-        // Read dictionary
-        fieldDictionary fieldDict(fieldObject, fieldObject.headerClassName());
-
-        vectorField internalVals("internalField", fieldDict, mesh().nCells());
-
-        applyToSet(action, mag(internalVals), set);
-    }
     else
     {
-        WarningInFunction
+        typeIOobject<volVectorField> fieldObject
+        (
+            fieldName_,
+            mesh().time().timeName(),
+            mesh(),
+            IOobject::MUST_READ,
+            IOobject::AUTO_WRITE,
+            false
+        );
+
+        if (fieldObject.IOobject::headerOk())
+        {
+            IFstream str(fieldObject.filePath());
+
+            // Read dictionary
+            const fieldDictionary fieldDict
+            (
+                fieldObject,
+                volVectorField::typeName
+            );
+
+            const vectorField internalVals
+            (
+                "internalField",
+                fieldDict, mesh().nCells()
+            );
+
+            applyToSet(action, mag(internalVals), set);
+        }
+        else
+        {
+            WarningInFunction
             << "Cannot handle fields of type " << fieldObject.headerClassName()
             << endl;
+        }
     }
 }
 
diff --git a/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.H b/src/finiteVolume/sets/cellSources/fieldToCell/fieldToCell.H
similarity index 100%
rename from src/meshTools/sets/cellSources/fieldToCell/fieldToCell.H
rename to src/finiteVolume/sets/cellSources/fieldToCell/fieldToCell.H
diff --git a/src/meshTools/sets/faceSources/patchFluxToFace/patchFluxToFace.C b/src/finiteVolume/sets/faceSources/patchFluxToFace/patchFluxToFace.C
similarity index 89%
rename from src/meshTools/sets/faceSources/patchFluxToFace/patchFluxToFace.C
rename to src/finiteVolume/sets/faceSources/patchFluxToFace/patchFluxToFace.C
index 10a96eb4eb..fc26b5e036 100644
--- a/src/meshTools/sets/faceSources/patchFluxToFace/patchFluxToFace.C
+++ b/src/finiteVolume/sets/faceSources/patchFluxToFace/patchFluxToFace.C
@@ -29,6 +29,7 @@ License
 #include "Time.H"
 #include "IFstream.H"
 #include "fieldDictionary.H"
+#include "surfaceFields.H"
 #include "addToRunTimeSelectionTable.H"
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
@@ -132,8 +133,7 @@ void Foam::patchFluxToFace::applyToSet
     topoSet& set
 ) const
 {
-    // Try to load field
-    IOobject fieldObject
+    typeIOobject<surfaceScalarField> fieldObject
     (
         fieldName_,
         mesh().time().timeName(),
@@ -143,17 +143,9 @@ void Foam::patchFluxToFace::applyToSet
         false
     );
 
-    // Note: should check for surfaceScalarField but that introduces dependency
-    //       on volMesh so just use another type with processor-local scope
-    if (!fieldObject.typeHeaderOk<labelIOList>(false))
+    if (fieldObject.headerOk())
     {
-        WarningInFunction
-            << "Cannot read flux field " << fieldName_
-            << " from time " << mesh().time().timeName() << endl;
-    }
-    else if (fieldObject.headerClassName() == "surfaceScalarField")
-    {
-        IFstream str(typeFilePath<labelIOList>(fieldObject));
+        IFstream str(fieldObject.filePath());
 
         // Read dictionary
         const fieldDictionary fieldDict
@@ -174,8 +166,8 @@ void Foam::patchFluxToFace::applyToSet
     else
     {
         WarningInFunction
-            << "Incorrect flux field type " << fieldObject.headerClassName()
-            << endl;
+            << "Cannot read flux field " << fieldName_
+            << " from time " << mesh().time().timeName() << endl;
     }
 }
 
diff --git a/src/meshTools/sets/faceSources/patchFluxToFace/patchFluxToFace.H b/src/finiteVolume/sets/faceSources/patchFluxToFace/patchFluxToFace.H
similarity index 100%
rename from src/meshTools/sets/faceSources/patchFluxToFace/patchFluxToFace.H
rename to src/finiteVolume/sets/faceSources/patchFluxToFace/patchFluxToFace.H
diff --git a/src/functionObjects/field/fieldAverage/fieldAverage.C b/src/functionObjects/field/fieldAverage/fieldAverage.C
index 794bca26bb..1a67f8e973 100644
--- a/src/functionObjects/field/fieldAverage/fieldAverage.C
+++ b/src/functionObjects/field/fieldAverage/fieldAverage.C
@@ -243,7 +243,7 @@ void Foam::functionObjects::fieldAverage::readAveragingProperties()
     }
     else
     {
-        IOobject propsDictHeader
+        typeIOobject<timeIOdictionary> propsDictHeader
         (
             name() + "Properties",
             obr_.time().timeName(obr_.time().startTime().value()),
@@ -254,7 +254,7 @@ void Foam::functionObjects::fieldAverage::readAveragingProperties()
             false
         );
 
-        if (!propsDictHeader.typeHeaderOk<timeIOdictionary>())
+        if (!propsDictHeader.headerOk())
         {
             Log << "    Starting averaging at time "
                 << obr_.time().timeName() << nl;
diff --git a/src/functionObjects/field/fieldCoordinateSystemTransform/fieldCoordinateSystemTransformTemplates.C b/src/functionObjects/field/fieldCoordinateSystemTransform/fieldCoordinateSystemTransformTemplates.C
index 8b44b3fb23..5204f7dc79 100644
--- a/src/functionObjects/field/fieldCoordinateSystemTransform/fieldCoordinateSystemTransformTemplates.C
+++ b/src/functionObjects/field/fieldCoordinateSystemTransform/fieldCoordinateSystemTransformTemplates.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -79,7 +79,7 @@ void Foam::functionObjects::fieldCoordinateSystemTransform::transform
     }
     else
     {
-        IOobject fieldHeader
+        typeIOobject<VolFieldType> fieldHeader
         (
             fieldName,
             mesh_.time().timeName(),
@@ -88,11 +88,7 @@ void Foam::functionObjects::fieldCoordinateSystemTransform::transform
             IOobject::NO_WRITE
         );
 
-        if
-        (
-            fieldHeader.typeHeaderOk<VolFieldType>(false)
-         && fieldHeader.headerClassName() == VolFieldType::typeName
-        )
+        if (fieldHeader.headerOk())
         {
             DebugInfo
                 << type() << ": Field " << fieldName << " read from file"
@@ -103,20 +99,28 @@ void Foam::functionObjects::fieldCoordinateSystemTransform::transform
                 mesh_.lookupObject<VolFieldType>(fieldName)
             );
         }
-        else if
-        (
-            fieldHeader.typeHeaderOk<SurfaceFieldType>(false)
-         && fieldHeader.headerClassName() == SurfaceFieldType::typeName
-        )
+        else
         {
-            DebugInfo
-                << type() << ": Field " << fieldName << " read from file"
-                << endl;
-
-            transformField<SurfaceFieldType>
+            typeIOobject<SurfaceFieldType> fieldHeader
             (
-                mesh_.lookupObject<SurfaceFieldType>(fieldName)
+                fieldName,
+                mesh_.time().timeName(),
+                mesh_,
+                IOobject::MUST_READ,
+                IOobject::NO_WRITE
             );
+
+            if (fieldHeader.headerOk())
+            {
+                DebugInfo
+                    << type() << ": Field " << fieldName << " read from file"
+                    << endl;
+
+                transformField<SurfaceFieldType>
+                (
+                    mesh_.lookupObject<SurfaceFieldType>(fieldName)
+                );
+            }
         }
     }
 }
diff --git a/src/functionObjects/field/readFields/readFieldsTemplates.C b/src/functionObjects/field/readFields/readFieldsTemplates.C
index db024808c1..4d3f19eeb3 100644
--- a/src/functionObjects/field/readFields/readFieldsTemplates.C
+++ b/src/functionObjects/field/readFields/readFieldsTemplates.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -55,7 +55,7 @@ void Foam::functionObjects::readFields::loadField
     }
     else
     {
-        IOobject fieldHeader
+        typeIOobject<VolFieldType> fieldHeader
         (
             fieldName,
             mesh_.time().timeName(),
@@ -64,11 +64,7 @@ void Foam::functionObjects::readFields::loadField
             IOobject::NO_WRITE
         );
 
-        if
-        (
-            fieldHeader.typeHeaderOk<VolFieldType>(false)
-         && fieldHeader.headerClassName() == VolFieldType::typeName
-        )
+        if (fieldHeader.headerOk())
         {
             // Store field locally
             Log << "    Reading " << fieldName << endl;
@@ -77,18 +73,26 @@ void Foam::functionObjects::readFields::loadField
             vflds.setSize(sz+1);
             vflds.set(sz, new VolFieldType(fieldHeader, mesh_));
         }
-        else if
-        (
-            fieldHeader.typeHeaderOk<SurfaceFieldType>(false)
-         && fieldHeader.headerClassName() == SurfaceFieldType::typeName
-        )
+        else
         {
-            // Store field locally
-            Log << "    Reading " << fieldName << endl;
+            typeIOobject<SurfaceFieldType> fieldHeader
+            (
+                fieldName,
+                mesh_.time().timeName(),
+                mesh_,
+                IOobject::MUST_READ,
+                IOobject::NO_WRITE
+            );
 
-            label sz = sflds.size();
-            sflds.setSize(sz+1);
-            sflds.set(sz, new SurfaceFieldType(fieldHeader, mesh_));
+            if (fieldHeader.headerOk())
+            {
+                // Store field locally
+                Log << "    Reading " << fieldName << endl;
+
+                label sz = sflds.size();
+                sflds.setSize(sz+1);
+                sflds.set(sz, new SurfaceFieldType(fieldHeader, mesh_));
+            }
         }
     }
 }
diff --git a/src/functionObjects/utilities/writeDictionary/writeDictionary.C b/src/functionObjects/utilities/writeDictionary/writeDictionary.C
index 80633bab6d..1993f4cad6 100644
--- a/src/functionObjects/utilities/writeDictionary/writeDictionary.C
+++ b/src/functionObjects/utilities/writeDictionary/writeDictionary.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2013-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2013-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -56,7 +56,7 @@ bool Foam::functionObjects::writeDictionary::tryDirectory
     bool& firstDict
 )
 {
-    IOobject dictIO
+    typeIOobject<IOdictionary> dictIO
     (
         dictNames_[dictI],
         location,
@@ -66,7 +66,7 @@ bool Foam::functionObjects::writeDictionary::tryDirectory
         false
     );
 
-    if (dictIO.typeHeaderOk<IOdictionary>(true))
+    if (dictIO.headerOk())
     {
         IOdictionary dict(dictIO);
 
diff --git a/src/fvModels/derived/heatTransfer/heatTransferModels/constant/constant.C b/src/fvModels/derived/heatTransfer/heatTransferModels/constant/constant.C
index 6a7a130896..0e68770c1c 100644
--- a/src/fvModels/derived/heatTransfer/heatTransferModels/constant/constant.C
+++ b/src/fvModels/derived/heatTransfer/heatTransferModels/constant/constant.C
@@ -47,7 +47,7 @@ namespace heatTransferModels
 
 void Foam::fv::heatTransferModels::constant::readCoeffs()
 {
-    IOobject htcIO
+    typeIOobject<volScalarField> htcIO
     (
         "htc",
         mesh().time().constant(),
@@ -67,7 +67,7 @@ void Foam::fv::heatTransferModels::constant::readCoeffs()
             );
         htcPtr_.clear();
     }
-    else if (htcIO.typeHeaderOk<volScalarField>(false))
+    else if (htcIO.headerOk())
     {
         htc_ = dimensionedScalar("htc", dimPower/dimTemperature/dimArea, NaN);
         htcPtr_.set(new volScalarField(htcIO, mesh()));
@@ -77,7 +77,7 @@ void Foam::fv::heatTransferModels::constant::readCoeffs()
         FatalIOErrorInFunction(coeffs())
             << "Heat transfer coefficient (htc) not found. A uniform htc "
             << "value should be specified, or a non-uniform field should "
-            << "exist at " << htcIO.objectPath<volScalarField>()
+            << "exist at " << htcIO.objectPath()
             << exit(FatalIOError);
     }
 }
diff --git a/src/fvModels/derived/heatTransfer/heatTransferModels/heatTransferModel/heatTransferModel.C b/src/fvModels/derived/heatTransfer/heatTransferModels/heatTransferModel/heatTransferModel.C
index 8cdd71bdea..e8f655b297 100644
--- a/src/fvModels/derived/heatTransfer/heatTransferModels/heatTransferModel/heatTransferModel.C
+++ b/src/fvModels/derived/heatTransfer/heatTransferModels/heatTransferModel/heatTransferModel.C
@@ -42,7 +42,7 @@ namespace fv
 
 void Foam::fv::heatTransferModel::readCoeffs()
 {
-    IOobject AoVIO
+    typeIOobject<volScalarField> AoVIO
     (
         "AoV",
         mesh().time().constant(),
@@ -56,7 +56,7 @@ void Foam::fv::heatTransferModel::readCoeffs()
         AoV_ = dimensionedScalar("AoV", dimless/dimLength, coeffs());
         AoVPtr_.clear();
     }
-    else if (AoVIO.typeHeaderOk<volScalarField>(false))
+    else if (AoVIO.headerOk())
     {
         AoV_ = dimensionedScalar("AoV", dimless/dimLength, NaN);
         AoVPtr_.set(new volScalarField(AoVIO, mesh()));
@@ -66,7 +66,7 @@ void Foam::fv::heatTransferModel::readCoeffs()
         FatalIOErrorInFunction(coeffs())
             << "Area per unit volume (AoV) not found. A uniform AoV "
             << "value should be specified, or a non-uniform field should "
-            << "exist at " << AoVIO.objectPath<volScalarField>()
+            << "exist at " << AoVIO.objectPath()
             << exit(FatalIOError);
     }
 }
diff --git a/src/fvMotionSolver/fvMotionSolvers/displacement/laplacian/displacementLaplacianFvMotionSolver.C b/src/fvMotionSolver/fvMotionSolvers/displacement/laplacian/displacementLaplacianFvMotionSolver.C
index bce940015b..c040801887 100644
--- a/src/fvMotionSolver/fvMotionSolvers/displacement/laplacian/displacementLaplacianFvMotionSolver.C
+++ b/src/fvMotionSolver/fvMotionSolvers/displacement/laplacian/displacementLaplacianFvMotionSolver.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -88,7 +88,7 @@ Foam::displacementLaplacianFvMotionSolver::displacementLaplacianFvMotionSolver
       : -1
     )
 {
-    IOobject io
+    typeIOobject<pointVectorField> io
     (
         "pointLocation",
         fvMesh_.time().timeName(),
@@ -105,7 +105,7 @@ Foam::displacementLaplacianFvMotionSolver::displacementLaplacianFvMotionSolver
     }
 
 
-    if (io.typeHeaderOk<pointVectorField>(true))
+    if (io.headerOk())
     {
         pointLocation_.reset
         (
diff --git a/src/lagrangian/basic/Cloud/CloudIO.C b/src/lagrangian/basic/Cloud/CloudIO.C
index 6c2a99fe81..ee665d2799 100644
--- a/src/lagrangian/basic/Cloud/CloudIO.C
+++ b/src/lagrangian/basic/Cloud/CloudIO.C
@@ -39,7 +39,7 @@ Foam::word Foam::Cloud<ParticleType>::cloudPropertiesName("cloudProperties");
 template<class ParticleType>
 void Foam::Cloud<ParticleType>::readCloudUniformProperties()
 {
-    IOobject dictObj
+    typeIOobject<timeIOdictionary> dictObj
     (
         cloudPropertiesName,
         time().timeName(),
@@ -50,7 +50,7 @@ void Foam::Cloud<ParticleType>::readCloudUniformProperties()
         false
     );
 
-    if (dictObj.typeHeaderOk<timeIOdictionary>(true))
+    if (dictObj.headerOk())
     {
         const timeIOdictionary uniformPropsDict(dictObj);
 
diff --git a/src/lagrangian/basic/particle/particleTemplates.C b/src/lagrangian/basic/particle/particleTemplates.C
index a284a07b63..0578a38ec5 100644
--- a/src/lagrangian/basic/particle/particleTemplates.C
+++ b/src/lagrangian/basic/particle/particleTemplates.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -44,9 +44,12 @@ void Foam::particle::readFields(TrackCloudType& c)
 {
     bool valid = c.size();
 
-    IOobject procIO(c.fieldIOobject("origProcId", IOobject::MUST_READ));
+    typeIOobject<IOField<label>> procIO
+    (
+        c.fieldIOobject("origProcId", IOobject::MUST_READ)
+    );
 
-    bool haveFile = procIO.typeHeaderOk<IOField<label>>(true);
+    bool haveFile = procIO.headerOk();
 
     IOField<label> origProcId(procIO, valid && haveFile);
     c.checkFieldIOobject(c, origProcId);
diff --git a/src/lagrangian/parcel/parcelCloudList/parcelCloudList.C b/src/lagrangian/parcel/parcelCloudList/parcelCloudList.C
index 6af4fac250..c776ee8dfd 100644
--- a/src/lagrangian/parcel/parcelCloudList/parcelCloudList.C
+++ b/src/lagrangian/parcel/parcelCloudList/parcelCloudList.C
@@ -41,7 +41,7 @@ void Foam::parcelCloudList::initialise
     const Args& ... args
 )
 {
-    IOobject cloudsIO
+    typeIOobject<wordGlobalIOList> cloudsIO
     (
         cloudsName,
         mesh_.time().constant(),
@@ -50,7 +50,7 @@ void Foam::parcelCloudList::initialise
         IOobject::NO_WRITE
     );
 
-    if (cloudsIO.typeHeaderOk<wordGlobalIOList>(false))
+    if (cloudsIO.headerOk())
     {
         wordGlobalIOList cloudNames(cloudsIO);
 
@@ -63,7 +63,7 @@ void Foam::parcelCloudList::initialise
     }
     else
     {
-        IOobject cloudIO
+        typeIOobject<IOdictionary> cloudIO
         (
             "cloudProperties",
             mesh_.time().constant(),
@@ -72,7 +72,7 @@ void Foam::parcelCloudList::initialise
             IOobject::NO_WRITE
         );
 
-        if (cloudIO.typeHeaderOk<IOdictionary>(false))
+        if (cloudIO.headerOk())
         {
             this->setSize(1);
 
diff --git a/src/lagrangian/parcel/submodels/CloudFunctionObjects/PatchCollisionDensity/PatchCollisionDensity.C b/src/lagrangian/parcel/submodels/CloudFunctionObjects/PatchCollisionDensity/PatchCollisionDensity.C
index b938726299..58dd867ec1 100644
--- a/src/lagrangian/parcel/submodels/CloudFunctionObjects/PatchCollisionDensity/PatchCollisionDensity.C
+++ b/src/lagrangian/parcel/submodels/CloudFunctionObjects/PatchCollisionDensity/PatchCollisionDensity.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2018-2020 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2018-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -101,7 +101,7 @@ Foam::PatchCollisionDensity<CloudType>::PatchCollisionDensity
     collisionDensity_ == 0;
     collisionDensity0_ == 0;
 
-    IOobject io
+    typeIOobject<volScalarField> io
     (
         this->owner().name() + ":collisionDensity",
         this->owner().mesh().time().timeName(),
@@ -110,7 +110,7 @@ Foam::PatchCollisionDensity<CloudType>::PatchCollisionDensity
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<volScalarField>())
+    if (io.headerOk())
     {
         const volScalarField collisionDensity(io, this->owner().mesh());
         collisionDensity_ == collisionDensity.boundaryField();
diff --git a/src/mesh/snappyHexMesh/refinementFeatures/refinementFeatures.C b/src/mesh/snappyHexMesh/refinementFeatures/refinementFeatures.C
index 79b33ed3db..7c8c499414 100644
--- a/src/mesh/snappyHexMesh/refinementFeatures/refinementFeatures.C
+++ b/src/mesh/snappyHexMesh/refinementFeatures/refinementFeatures.C
@@ -46,7 +46,7 @@ void Foam::refinementFeatures::read
 
         // Try reading extendedEdgeMesh first
 
-        IOobject extFeatObj
+        typeIOobject<extendedFeatureEdgeMesh> extFeatObj
         (
             featFileName,                       // name
             io.time().constant(),               // instance
@@ -57,7 +57,7 @@ void Foam::refinementFeatures::read
             false
         );
 
-        const fileName fName(typeFilePath<extendedFeatureEdgeMesh>(extFeatObj));
+        const fileName fName(extFeatObj.filePath());
 
         if (!fName.empty() && extendedEdgeMesh::canRead(fName))
         {
@@ -77,7 +77,7 @@ void Foam::refinementFeatures::read
         {
             // Try reading edgeMesh
 
-            IOobject featObj
+            typeIOobject<featureEdgeMesh> featObj
             (
                 featFileName,
                 io.time().constant(),
@@ -88,7 +88,7 @@ void Foam::refinementFeatures::read
                 false
             );
 
-            const fileName fName(typeFilePath<featureEdgeMesh>(featObj));
+            const fileName fName(featObj.filePath());
 
             if (fName.empty())
             {
@@ -96,7 +96,7 @@ void Foam::refinementFeatures::read
                 (
                     dict
                 )   << "Could not open "
-                    << featObj.objectPath<featureEdgeMesh>()
+                    << featObj.objectPath()
                     << exit(FatalIOError);
             }
 
diff --git a/src/meshTools/Make/files b/src/meshTools/Make/files
index 584849a332..bb9dbdbc6c 100644
--- a/src/meshTools/Make/files
+++ b/src/meshTools/Make/files
@@ -128,9 +128,8 @@ $(topoSets)/pointZoneSet.C
 
 sets/topoSetSource/topoSetSource.C
 
-cellSources =  sets/cellSources
+cellSources = sets/cellSources
 $(cellSources)/faceToCell/faceToCell.C
-$(cellSources)/fieldToCell/fieldToCell.C
 $(cellSources)/pointToCell/pointToCell.C
 $(cellSources)/shapeToCell/shapeToCell.C
 $(cellSources)/boxToCell/boxToCell.C
@@ -154,15 +153,14 @@ $(faceSources)/faceToFace/faceToFace.C
 $(faceSources)/labelToFace/labelToFace.C
 $(faceSources)/cellToFace/cellToFace.C
 $(faceSources)/normalToFace/normalToFace.C
-$(faceSources)/pointToFace/pointToFace.C
 $(faceSources)/patchToFace/patchToFace.C
+$(faceSources)/pointToFace/pointToFace.C
 $(faceSources)/boundaryToFace/boundaryToFace.C
 $(faceSources)/zoneToFace/zoneToFace.C
 $(faceSources)/boxToFace/boxToFace.C
 $(faceSources)/regionToFace/regionToFace.C
 $(faceSources)/cylinderToFace/cylinderToFace.C
 $(faceSources)/cylinderAnnulusToFace/cylinderAnnulusToFace.C
-$(faceSources)/patchFluxToFace/patchFluxToFace.C
 
 pointSources = sets/pointSources
 $(pointSources)/labelToPoint/labelToPoint.C
diff --git a/src/meshTools/edgeMesh/edgeMeshFormats/edgeMesh/edgeMeshFormat.C b/src/meshTools/edgeMesh/edgeMeshFormats/edgeMesh/edgeMeshFormat.C
index 55940dfe16..6447b8ca02 100644
--- a/src/meshTools/edgeMesh/edgeMeshFormats/edgeMesh/edgeMeshFormat.C
+++ b/src/meshTools/edgeMesh/edgeMeshFormats/edgeMesh/edgeMeshFormat.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -66,7 +66,7 @@ bool Foam::fileFormats::edgeMeshFormat::read
 
     // Construct IOobject to re-use the headerOk & readHeader
     // (so we can read ascii and binary)
-    IOobject io
+    typeIOobject<featureEdgeMesh> io
     (
         filename,
         dummyTime,
@@ -75,14 +75,14 @@ bool Foam::fileFormats::edgeMeshFormat::read
         false
     );
 
-    if (!io.typeHeaderOk<featureEdgeMesh>(false))
+    if (!io.headerOk())
     {
         FatalErrorInFunction
             << "Cannot read file " << filename
             << exit(FatalError);
     }
 
-    const fileName fName(typeFilePath<featureEdgeMesh>(io));
+    const fileName fName(io.filePath());
 
     autoPtr<IFstream> isPtr(new IFstream(fName));
     bool ok = false;
diff --git a/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMeshFormats/extendedEdgeMeshFormat/extendedEdgeMeshFormat.C b/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMeshFormats/extendedEdgeMeshFormat/extendedEdgeMeshFormat.C
index 90b4df17f2..82d4036338 100644
--- a/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMeshFormats/extendedEdgeMeshFormat/extendedEdgeMeshFormat.C
+++ b/src/meshTools/edgeMesh/extendedEdgeMesh/extendedEdgeMeshFormats/extendedEdgeMeshFormat/extendedEdgeMeshFormat.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2013-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2013-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -64,7 +64,7 @@ bool Foam::fileFormats::extendedEdgeMeshFormat::read
 
     // Construct IOobject to re-use the headerOk & readHeader
     // (so we can read ascii and binary)
-    IOobject io
+    typeIOobject<extendedFeatureEdgeMesh> io
     (
         filename,
         dummyTime,
@@ -73,14 +73,14 @@ bool Foam::fileFormats::extendedEdgeMeshFormat::read
         false
     );
 
-    if (!io.typeHeaderOk<extendedFeatureEdgeMesh>(false))
+    if (!io.headerOk())
     {
         FatalErrorInFunction
             << "Cannot read file " << filename
             << exit(FatalError);
     }
 
-    const fileName fName(typeFilePath<extendedFeatureEdgeMesh>(io));
+    const fileName fName(io.filePath());
 
     autoPtr<IFstream> isPtr(new IFstream(fName));
     bool ok = false;
diff --git a/src/parallel/reconstruct/reconstruct/reconstructLagrangianFields.C b/src/parallel/reconstruct/reconstruct/reconstructLagrangianFields.C
index 0b7865f210..8a904f230b 100644
--- a/src/parallel/reconstruct/reconstruct/reconstructLagrangianFields.C
+++ b/src/parallel/reconstruct/reconstruct/reconstructLagrangianFields.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -60,7 +60,7 @@ Foam::tmp<Foam::IOField<Type>> Foam::reconstructLagrangianField
     forAll(meshes, i)
     {
         // Check object on local mesh
-        IOobject localIOobject
+        typeIOobject<IOField<Type>> localIOobject
         (
             fieldName,
             meshes[i].time().timeName(),
@@ -70,7 +70,7 @@ Foam::tmp<Foam::IOField<Type>> Foam::reconstructLagrangianField
             IOobject::NO_WRITE
         );
 
-        if (localIOobject.typeHeaderOk<IOField<Type>>(true))
+        if (localIOobject.headerOk())
         {
             IOField<Type> fieldi(localIOobject);
 
@@ -119,7 +119,7 @@ Foam::reconstructLagrangianFieldField
 
     forAll(meshes, i)
     {
-        // Check object on local mesh
+        // No type checking is done to handle CompactIOField and IOField
         IOobject localIOobject
         (
             fieldName,
@@ -130,14 +130,7 @@ Foam::reconstructLagrangianFieldField
             IOobject::NO_WRITE
         );
 
-        if
-        (
-            localIOobject.typeHeaderOk<CompactIOField<Field<Type>, Type>>
-            (
-                false
-            )
-         || localIOobject.typeHeaderOk<IOField<Field<Type>>>(false)
-        )
+        if (localIOobject.headerOk())
         {
             CompactIOField<Field<Type>, Type> fieldi(localIOobject);
 
diff --git a/src/physicalProperties/physicalProperties/physicalProperties.C b/src/physicalProperties/physicalProperties/physicalProperties.C
index fbd7610777..c943e2144b 100644
--- a/src/physicalProperties/physicalProperties/physicalProperties.C
+++ b/src/physicalProperties/physicalProperties/physicalProperties.C
@@ -43,7 +43,7 @@ Foam::IOobject Foam::physicalProperties::findModelDict
     bool registerObject
 )
 {
-    IOobject physicalPropertiesIO
+    typeIOobject<IOdictionary> physicalPropertiesIO
     (
         IOobject::groupName(physicalProperties::typeName, group),
         obr.time().constant(),
@@ -53,13 +53,13 @@ Foam::IOobject Foam::physicalProperties::findModelDict
         registerObject
     );
 
-    if (physicalPropertiesIO.typeHeaderOk<IOdictionary>(true))
+    if (physicalPropertiesIO.headerOk())
     {
         return physicalPropertiesIO;
     }
     else
     {
-        IOobject thermophysicalPropertiesIO
+        typeIOobject<IOdictionary> thermophysicalPropertiesIO
         (
             IOobject::groupName("thermophysicalProperties", group),
             obr.time().constant(),
@@ -69,13 +69,13 @@ Foam::IOobject Foam::physicalProperties::findModelDict
             registerObject
         );
 
-        if (thermophysicalPropertiesIO.typeHeaderOk<IOdictionary>(true))
+        if (thermophysicalPropertiesIO.headerOk())
         {
             return thermophysicalPropertiesIO;
         }
         else
         {
-            IOobject transportPropertiesIO
+            typeIOobject<IOdictionary> transportPropertiesIO
             (
                 IOobject::groupName("transportProperties", group),
                 obr.time().constant(),
@@ -85,7 +85,7 @@ Foam::IOobject Foam::physicalProperties::findModelDict
                 registerObject
             );
 
-            if (transportPropertiesIO.typeHeaderOk<IOdictionary>(true))
+            if (transportPropertiesIO.headerOk())
             {
                 return transportPropertiesIO;
             }
diff --git a/src/radiationModels/radiationModels/fvDOM/radiativeIntensityRay/radiativeIntensityRay.C b/src/radiationModels/radiationModels/fvDOM/radiativeIntensityRay/radiativeIntensityRay.C
index d9679d7fd7..1e183acce1 100644
--- a/src/radiationModels/radiationModels/fvDOM/radiativeIntensityRay/radiativeIntensityRay.C
+++ b/src/radiationModels/radiationModels/fvDOM/radiativeIntensityRay/radiativeIntensityRay.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -177,7 +177,7 @@ Foam::radiationModels::radiativeIntensityRay::radiativeIntensityRay
 
     forAll(ILambda_, lambdaI)
     {
-        IOobject IHeader
+        typeIOobject<volScalarField> IHeader
         (
             intensityPrefix + "_" + name(rayId) + "_" + name(lambdaI),
             mesh_.time().timeName(),
@@ -187,7 +187,7 @@ Foam::radiationModels::radiativeIntensityRay::radiativeIntensityRay
         );
 
         // Check if field exists and can be read
-        if (IHeader.typeHeaderOk<volScalarField>(true))
+        if (IHeader.headerOk())
         {
             ILambda_.set
             (
diff --git a/src/radiationModels/radiationModels/radiationModel/radiationModel.C b/src/radiationModels/radiationModels/radiationModel/radiationModel.C
index e1011e5598..8540caff64 100644
--- a/src/radiationModels/radiationModels/radiationModel/radiationModel.C
+++ b/src/radiationModels/radiationModels/radiationModel/radiationModel.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2019 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -44,7 +44,7 @@ namespace Foam
 
 Foam::IOobject Foam::radiationModel::createIOobject(const fvMesh& mesh) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         "radiationProperties",
         mesh.time().constant(),
@@ -53,7 +53,7 @@ Foam::IOobject Foam::radiationModel::createIOobject(const fvMesh& mesh) const
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         io.readOpt() = IOobject::MUST_READ_IF_MODIFIED;
         return io;
diff --git a/src/regionModels/surfaceFilmModels/surfaceFilmModel/surfaceFilmModelNew.C b/src/regionModels/surfaceFilmModels/surfaceFilmModel/surfaceFilmModelNew.C
index 1620bcf5b7..84bde3bca1 100644
--- a/src/regionModels/surfaceFilmModels/surfaceFilmModel/surfaceFilmModelNew.C
+++ b/src/regionModels/surfaceFilmModels/surfaceFilmModel/surfaceFilmModelNew.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2021 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -45,7 +45,7 @@ autoPtr<surfaceFilmModel> surfaceFilmModel::New
     word modelType;
 
     {
-        IOobject surfaceFilmPropertiesDictHeader
+        typeIOobject<IOdictionary> surfaceFilmPropertiesDictHeader
         (
             regionType + "Properties",
             mesh.time().constant(),
@@ -55,7 +55,7 @@ autoPtr<surfaceFilmModel> surfaceFilmModel::New
             false
         );
 
-        if (surfaceFilmPropertiesDictHeader.typeHeaderOk<IOdictionary>())
+        if (surfaceFilmPropertiesDictHeader.headerOk())
         {
             IOdictionary surfaceFilmPropertiesDict
             (
diff --git a/src/rigidBodyMeshMotion/rigidBodyMeshMotion/rigidBodyMeshMotion.C b/src/rigidBodyMeshMotion/rigidBodyMeshMotion/rigidBodyMeshMotion.C
index b78c4da9af..73884c3e9b 100644
--- a/src/rigidBodyMeshMotion/rigidBodyMeshMotion/rigidBodyMeshMotion.C
+++ b/src/rigidBodyMeshMotion/rigidBodyMeshMotion/rigidBodyMeshMotion.C
@@ -92,13 +92,13 @@ Foam::rigidBodyMeshMotion::rigidBodyMeshMotion
     RBD::rigidBodyMotion
     (
         coeffDict(),
-        IOobject
+        typeIOobject<timeIOdictionary>
         (
             "rigidBodyMotionState",
             mesh.time().timeName(),
             "uniform",
             mesh
-        ).typeHeaderOk<timeIOdictionary>(true)
+        ).headerOk()
       ? timeIOdictionary
         (
             IOobject
diff --git a/src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C b/src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C
index 8fdfb14f1a..0550be55b7 100644
--- a/src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C
+++ b/src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C
@@ -76,13 +76,13 @@ Foam::rigidBodyMeshMotionSolver::rigidBodyMeshMotionSolver
     RBD::rigidBodyMotion
     (
         coeffDict(),
-        IOobject
+        typeIOobject<timeIOdictionary>
         (
             "rigidBodyMotionState",
             mesh.time().timeName(),
             "uniform",
             mesh
-        ).typeHeaderOk<timeIOdictionary>(true)
+        ).headerOk()
       ? timeIOdictionary
         (
             IOobject
diff --git a/src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionSolver/sixDoFRigidBodyMotionSolver.C b/src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionSolver/sixDoFRigidBodyMotionSolver.C
index edf6ed3989..39710d4c93 100644
--- a/src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionSolver/sixDoFRigidBodyMotionSolver.C
+++ b/src/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionSolver/sixDoFRigidBodyMotionSolver.C
@@ -60,13 +60,13 @@ Foam::sixDoFRigidBodyMotionSolver::sixDoFRigidBodyMotionSolver
     sixDoFRigidBodyMotion
     (
         coeffDict(),
-        IOobject
+        typeIOobject<timeIOdictionary>
         (
             "sixDoFRigidBodyMotionState",
             mesh.time().timeName(),
             "uniform",
             mesh
-        ).typeHeaderOk<timeIOdictionary>(true)
+        ).headerOk()
       ? timeIOdictionary
         (
             IOobject
diff --git a/src/thermophysicalModels/chemistryModel/chemistryModel/TDACChemistryModel/TDACChemistryModel.C b/src/thermophysicalModels/chemistryModel/chemistryModel/TDACChemistryModel/TDACChemistryModel.C
index 83a23b5f92..8749e7aeee 100644
--- a/src/thermophysicalModels/chemistryModel/chemistryModel/TDACChemistryModel/TDACChemistryModel.C
+++ b/src/thermophysicalModels/chemistryModel/chemistryModel/TDACChemistryModel/TDACChemistryModel.C
@@ -71,7 +71,7 @@ Foam::TDACChemistryModel<ThermoType>::TDACChemistryModel
     {
         forAll(this->Y(), i)
         {
-            IOobject header
+            typeIOobject<volScalarField> header
             (
                 this->Y()[i].name(),
                 this->mesh().time().timeName(),
@@ -81,7 +81,7 @@ Foam::TDACChemistryModel<ThermoType>::TDACChemistryModel
 
             // Check if the species file is provided, if not set inactive
             // and NO_WRITE
-            if (!header.typeHeaderOk<volScalarField>(true))
+            if (!header.headerOk())
             {
                 composition.setInactive(i);
             }
diff --git a/src/thermophysicalModels/reactionThermo/mixtures/basicSpecieMixture/basicSpecieMixture.C b/src/thermophysicalModels/reactionThermo/mixtures/basicSpecieMixture/basicSpecieMixture.C
index 856e2f0713..23d0afd825 100644
--- a/src/thermophysicalModels/reactionThermo/mixtures/basicSpecieMixture/basicSpecieMixture.C
+++ b/src/thermophysicalModels/reactionThermo/mixtures/basicSpecieMixture/basicSpecieMixture.C
@@ -78,7 +78,7 @@ Foam::basicSpecieMixture::basicSpecieMixture
 
     forAll(species_, i)
     {
-        IOobject header
+        typeIOobject<volScalarField> header
         (
             IOobject::groupName(species_[i], phaseName),
             mesh.time().timeName(),
@@ -87,7 +87,7 @@ Foam::basicSpecieMixture::basicSpecieMixture
         );
 
         // check if field exists and can be read
-        if (header.typeHeaderOk<volScalarField>(true))
+        if (header.headerOk())
         {
             Y_.set
             (
@@ -116,7 +116,7 @@ Foam::basicSpecieMixture::basicSpecieMixture
                     IOobject::groupName("Ydefault", phaseName)
                 );
 
-                IOobject timeIO
+                typeIOobject<volScalarField> timeIO
                 (
                     YdefaultName,
                     mesh.time().timeName(),
@@ -125,7 +125,7 @@ Foam::basicSpecieMixture::basicSpecieMixture
                     IOobject::NO_WRITE
                 );
 
-                IOobject constantIO
+                typeIOobject<volScalarField> constantIO
                 (
                     YdefaultName,
                     mesh.time().constant(),
@@ -134,7 +134,7 @@ Foam::basicSpecieMixture::basicSpecieMixture
                     IOobject::NO_WRITE
                 );
 
-                IOobject time0IO
+                typeIOobject<volScalarField> time0IO
                 (
                     YdefaultName,
                     Time::timeName(0),
@@ -143,11 +143,11 @@ Foam::basicSpecieMixture::basicSpecieMixture
                     IOobject::NO_WRITE
                 );
 
-                if (timeIO.typeHeaderOk<volScalarField>(true))
+                if (timeIO.headerOk())
                 {
                     tYdefault = new volScalarField(timeIO, mesh);
                 }
-                else if (constantIO.typeHeaderOk<volScalarField>(true))
+                else if (constantIO.headerOk())
                 {
                     tYdefault = new volScalarField(constantIO, mesh);
                 }
diff --git a/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C b/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
index b5a5df8cec..36cf9259d4 100644
--- a/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
+++ b/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModel.C
@@ -46,7 +46,7 @@ Foam::IOobject Foam::twoPhaseChangeModel::createIOobject
     const immiscibleIncompressibleTwoPhaseMixture& mixture
 ) const
 {
-    IOobject io
+    typeIOobject<IOdictionary> io
     (
         phaseChangePropertiesName,
         mixture.U().mesh().time().constant(),
@@ -55,7 +55,7 @@ Foam::IOobject Foam::twoPhaseChangeModel::createIOobject
         IOobject::NO_WRITE
     );
 
-    if (io.typeHeaderOk<IOdictionary>(true))
+    if (io.headerOk())
     {
         io.readOpt() = IOobject::MUST_READ_IF_MODIFIED;
         return io;
diff --git a/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C b/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
index 56c27d36f8..6fa019ddf6 100644
--- a/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
+++ b/src/twoPhaseModels/twoPhaseChange/twoPhaseChangeModel/twoPhaseChangeModelNew.C
@@ -32,7 +32,7 @@ Foam::autoPtr<Foam::twoPhaseChangeModel> Foam::twoPhaseChangeModel::New
     const immiscibleIncompressibleTwoPhaseMixture& mixture
 )
 {
-    IOobject twoPhaseChangeModelIO
+    typeIOobject<IOdictionary> twoPhaseChangeModelIO
     (
         IOobject
         (
@@ -47,7 +47,7 @@ Foam::autoPtr<Foam::twoPhaseChangeModel> Foam::twoPhaseChangeModel::New
 
     word modelType(twoPhaseChangeModels::noPhaseChange::typeName);
 
-    if (twoPhaseChangeModelIO.typeHeaderOk<IOdictionary>(false))
+    if (twoPhaseChangeModelIO.headerOk())
     {
         IOdictionary(twoPhaseChangeModelIO).lookup
         (
diff --git a/src/twoPhaseModels/twoPhaseMixture/VoF/createAlphaFluxes.H b/src/twoPhaseModels/twoPhaseMixture/VoF/createAlphaFluxes.H
index 0fa8981b74..2384ddac04 100644
--- a/src/twoPhaseModels/twoPhaseMixture/VoF/createAlphaFluxes.H
+++ b/src/twoPhaseModels/twoPhaseMixture/VoF/createAlphaFluxes.H
@@ -1,4 +1,4 @@
-IOobject alphaPhi1Header
+typeIOobject<surfaceScalarField> alphaPhi1Header
 (
     IOobject::groupName("alphaPhi", alpha1.group()),
     runTime.timeName(),
@@ -7,7 +7,7 @@ IOobject alphaPhi1Header
     IOobject::AUTO_WRITE
 );
 
-const bool alphaRestart = alphaPhi1Header.typeHeaderOk<surfaceScalarField>();
+const bool alphaRestart = alphaPhi1Header.headerOk();
 
 if (alphaRestart)
 {
diff --git a/src/twoPhaseModels/twoPhaseMixture/twoPhaseMixture/twoPhaseMixture.C b/src/twoPhaseModels/twoPhaseMixture/twoPhaseMixture/twoPhaseMixture.C
index 91654b5587..2a9f52f0d8 100644
--- a/src/twoPhaseModels/twoPhaseMixture/twoPhaseMixture/twoPhaseMixture.C
+++ b/src/twoPhaseModels/twoPhaseMixture/twoPhaseMixture/twoPhaseMixture.C
@@ -40,7 +40,7 @@ Foam::IOdictionary Foam::twoPhaseMixture::readPhasePropertiesDict
     const objectRegistry& obr
 )
 {
-    IOobject phasePropertiesIO
+    typeIOobject<IOdictionary> phasePropertiesIO
     (
         "phaseProperties",
         obr.time().constant(),
@@ -50,13 +50,13 @@ Foam::IOdictionary Foam::twoPhaseMixture::readPhasePropertiesDict
         false
     );
 
-    if (phasePropertiesIO.typeHeaderOk<IOdictionary>(true))
+    if (phasePropertiesIO.headerOk())
     {
         return phasePropertiesIO;
     }
     else
     {
-        IOobject thermophysicalPropertiesIO
+        typeIOobject<IOdictionary> thermophysicalPropertiesIO
         (
             "thermophysicalProperties",
             obr.time().constant(),
@@ -66,7 +66,7 @@ Foam::IOdictionary Foam::twoPhaseMixture::readPhasePropertiesDict
             false
         );
 
-        if (thermophysicalPropertiesIO.typeHeaderOk<IOdictionary>(true))
+        if (thermophysicalPropertiesIO.headerOk())
         {
             IOdictionary phasePropertiesDict(thermophysicalPropertiesIO);
             phasePropertiesDict.rename("phaseProperties");
@@ -74,7 +74,7 @@ Foam::IOdictionary Foam::twoPhaseMixture::readPhasePropertiesDict
         }
         else
         {
-            IOobject transportPropertiesIO
+            typeIOobject<IOdictionary> transportPropertiesIO
             (
                 "transportProperties",
                 obr.time().constant(),
@@ -84,7 +84,7 @@ Foam::IOdictionary Foam::twoPhaseMixture::readPhasePropertiesDict
                 false
             );
 
-            if (transportPropertiesIO.typeHeaderOk<IOdictionary>(true))
+            if (transportPropertiesIO.headerOk())
             {
                 IOdictionary phasePropertiesDict(transportPropertiesIO);
                 phasePropertiesDict.rename("phaseProperties");