diff --git a/src/turbulenceModels/compressible/RAS/derivedFvPatchFields/wallFunctions/mutWallFunctions/mutkRoughWallFunction/mutkRoughWallFunctionFvPatchScalarField.C b/src/turbulenceModels/compressible/RAS/derivedFvPatchFields/wallFunctions/mutWallFunctions/mutkRoughWallFunction/mutkRoughWallFunctionFvPatchScalarField.C
index 67353e4319..3452692f0e 100644
--- a/src/turbulenceModels/compressible/RAS/derivedFvPatchFields/wallFunctions/mutWallFunctions/mutkRoughWallFunction/mutkRoughWallFunctionFvPatchScalarField.C
+++ b/src/turbulenceModels/compressible/RAS/derivedFvPatchFields/wallFunctions/mutWallFunctions/mutkRoughWallFunction/mutkRoughWallFunctionFvPatchScalarField.C
@@ -77,7 +77,7 @@ tmp<scalarField> mutkRoughWallFunctionFvPatchScalarField::calcMut() const
 
     const scalar Cmu25 = pow025(Cmu_);
 
-    tmp<scalarField> tmutw(new scalarField(patch().size(), 0.0));
+    tmp<scalarField> tmutw(new scalarField(*this));
     scalarField& mutw = tmutw();
 
     forAll(mutw, faceI)
diff --git a/src/turbulenceModels/incompressible/RAS/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutkRoughWallFunction/nutkRoughWallFunctionFvPatchScalarField.C b/src/turbulenceModels/incompressible/RAS/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutkRoughWallFunction/nutkRoughWallFunctionFvPatchScalarField.C
index fdd5428a71..ce9fe5465a 100644
--- a/src/turbulenceModels/incompressible/RAS/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutkRoughWallFunction/nutkRoughWallFunctionFvPatchScalarField.C
+++ b/src/turbulenceModels/incompressible/RAS/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutkRoughWallFunction/nutkRoughWallFunctionFvPatchScalarField.C
@@ -76,7 +76,7 @@ tmp<scalarField> nutkRoughWallFunctionFvPatchScalarField::calcNut() const
 
     const scalar Cmu25 = pow025(Cmu_);
 
-    tmp<scalarField> tnutw(new scalarField(patch().size(), 0.0));
+    tmp<scalarField> tnutw(new scalarField(*this));
     scalarField& nutw = tnutw();
 
     forAll(nutw, faceI)