diff --git a/applications/test/IOField/Test-IOField.cxx b/applications/test/IOField/Test-IOField.cxx
index 96f91d5e7e..e9f6123e40 100644
--- a/applications/test/IOField/Test-IOField.cxx
+++ b/applications/test/IOField/Test-IOField.cxx
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2017 OpenFOAM Foundation
-    Copyright (C) 2019-2022 OpenCFD Ltd.
+    Copyright (C) 2019-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -269,7 +269,7 @@ int main(int argc, char *argv[])
         ioOutput.rename(args.executable() + "-labels");
         Info<< "write " << ioOutput.objectRelPath() << endl;
         {
-            IOListRef<label>(ioOutput, ints).write();
+            IOList<label>::writeContents(ioOutput, ints);
         }
 
         ioOutput.rename(args.executable() + "-points");
diff --git a/applications/utilities/mesh/manipulation/checkMesh/checkTopology.C b/applications/utilities/mesh/manipulation/checkMesh/checkTopology.C
index 1c2decf3c2..8842ee73c9 100644
--- a/applications/utilities/mesh/manipulation/checkMesh/checkTopology.C
+++ b/applications/utilities/mesh/manipulation/checkMesh/checkTopology.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2017-2023 OpenCFD Ltd.
+    Copyright (C) 2017-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -700,19 +700,11 @@ Foam::label Foam::checkTopology
                 << mesh.time().timeName()/"cellToRegion"
                 << endl;
 
-            IOListRef<label>
+            IOList<label>::writeContents
             (
-                IOobject
-                (
-                    "cellToRegion",
-                    mesh.time().timeName(),
-                    mesh,
-                    IOobject::NO_READ,
-                    IOobject::NO_WRITE,
-                    IOobject::NO_REGISTER
-                ),
+                IOobject("cellToRegion", mesh.time().timeName(), mesh),
                 rs
-            ).write();
+            );
 
 
             // Points in multiple regions
diff --git a/applications/utilities/mesh/manipulation/renumberMesh/renumberMesh.C b/applications/utilities/mesh/manipulation/renumberMesh/renumberMesh.C
index 9a3eb42647..c5763634bd 100644
--- a/applications/utilities/mesh/manipulation/renumberMesh/renumberMesh.C
+++ b/applications/utilities/mesh/manipulation/renumberMesh/renumberMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2016-2024 OpenCFD Ltd.
+    Copyright (C) 2016-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -1913,13 +1913,13 @@ int main(int argc, char *argv[])
                 );
 
                 meshMapIO.resetHeader("cellMap");
-                IOListRef<label>(meshMapIO, map().cellMap()).write();
+                IOList<label>::writeContents(meshMapIO, map().cellMap());
 
                 meshMapIO.resetHeader("faceMap");
-                IOListRef<label>(meshMapIO, map().faceMap()).write();
+                IOList<label>::writeContents(meshMapIO, map().faceMap());
 
                 meshMapIO.resetHeader("pointMap");
-                IOListRef<label>(meshMapIO, map().pointMap()).write();
+                IOList<label>::writeContents(meshMapIO, map().pointMap());
             }
         }
 
diff --git a/applications/utilities/parallelProcessing/decomposePar/domainDecomposition.C b/applications/utilities/parallelProcessing/decomposePar/domainDecomposition.C
index b77f2777fb..3696708214 100644
--- a/applications/utilities/parallelProcessing/decomposePar/domainDecomposition.C
+++ b/applications/utilities/parallelProcessing/decomposePar/domainDecomposition.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2019-2024 OpenCFD Ltd.
+    Copyright (C) 2019-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -846,12 +846,9 @@ bool Foam::domainDecomposition::writeDecomposition(const bool decomposeSets)
                     "boundaryProcAddressing",
                     procMesh.facesInstance(),
                     polyMesh::meshSubDir/pointMesh::meshSubDir,
-                    procPointMesh.thisDb(),
-                    IOobject::NO_READ,
-                    IOobject::NO_WRITE,
-                    IOobject::NO_REGISTER
+                    procPointMesh.thisDb()
                 );
-                IOListRef<label>(ioAddr, boundaryProcAddressing).write();
+                IOList<label>::writeContents(ioAddr, boundaryProcAddressing);
             }
         }
 
@@ -1013,15 +1010,15 @@ bool Foam::domainDecomposition::writeDecomposition(const bool decomposeSets)
 
         // pointProcAddressing
         ioAddr.rename("pointProcAddressing");
-        IOListRef<label>(ioAddr, procPointAddressing_[proci]).write();
+        IOList<label>::writeContents(ioAddr, procPointAddressing_[proci]);
 
         // faceProcAddressing
         ioAddr.rename("faceProcAddressing");
-        IOListRef<label>(ioAddr, procFaceAddressing_[proci]).write();
+        IOList<label>::writeContents(ioAddr, procFaceAddressing_[proci]);
 
         // cellProcAddressing
         ioAddr.rename("cellProcAddressing");
-        IOListRef<label>(ioAddr, procCellAddressing_[proci]).write();
+        IOList<label>::writeContents(ioAddr, procCellAddressing_[proci]);
 
         // Write patch map for backwards compatibility.
         // (= identity map for original patches, -1 for processor patches)
@@ -1031,7 +1028,7 @@ bool Foam::domainDecomposition::writeDecomposition(const bool decomposeSets)
 
         // boundaryProcAddressing
         ioAddr.rename("boundaryProcAddressing");
-        IOListRef<label>(ioAddr, procBoundaryAddr).write();
+        IOList<label>::writeContents(ioAddr, procBoundaryAddr);
     }
 
 
diff --git a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
index 56eaa1d4d9..d4611d3f25 100644
--- a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
+++ b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2016-2024 OpenCFD Ltd.
+    Copyright (C) 2016-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -502,7 +502,7 @@ void writeMaps
 
     Info<< "    pointProcAddressing" << endl;
     ioAddr.rename("pointProcAddressing");
-    IOListRef<label>(ioAddr, pointProcAddressing).write();
+    IOList<label>::writeContents(ioAddr, pointProcAddressing);
 
     // From processor face to reconstructed mesh face
     Info<< "    faceProcAddressing" << endl;
@@ -551,13 +551,13 @@ void writeMaps
     // From processor cell to reconstructed mesh cell
     Info<< "    cellProcAddressing" << endl;
     ioAddr.rename("cellProcAddressing");
-    IOListRef<label>(ioAddr, cellProcAddressing).write();
+    IOList<label>::writeContents(ioAddr, cellProcAddressing);
 
 
     // From processor patch to reconstructed mesh patch
     Info<< "    boundaryProcAddressing" << endl;
     ioAddr.rename("boundaryProcAddressing");
-    IOListRef<label>(ioAddr, boundProcAddressing).write();
+    IOList<label>::writeContents(ioAddr, boundProcAddressing);
 
     Info<< endl;
 }
diff --git a/applications/utilities/parallelProcessing/redistributePar/redistributePar.C b/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
index 305ec95aca..4ac8fd1acb 100644
--- a/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
+++ b/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2015-2024 OpenCFD Ltd.
+    Copyright (C) 2015-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -461,19 +461,12 @@ void writeDecomposition
 {
     // Write the decomposition as labelList for use with 'manual'
     // decomposition method.
-    IOListRef<label>
+    IOList<label>::writeContents
     (
-        IOobject
-        (
-            "cellDecomposition",
-            mesh.facesInstance(),  // mesh read from facesInstance
-            mesh,
-            IOobjectOption::NO_READ,
-            IOobjectOption::NO_WRITE,
-            IOobjectOption::NO_REGISTER
-        ),
+        // NB: mesh read from facesInstance
+        IOobject("cellDecomposition", mesh.facesInstance(), mesh),
         decomp
-    ).write();
+    );
 
     InfoOrPout
         << "Writing wanted cell distribution to volScalarField " << name
@@ -991,7 +984,8 @@ autoPtr<mapDistributePolyMesh> redistributeAndWrite
             polyMesh::meshSubDir,
             mesh.thisDb(),
             IOobjectOption::NO_READ,
-            IOobjectOption::AUTO_WRITE
+            IOobjectOption::AUTO_WRITE,
+            IOobjectOption::REGISTER
         ),
         distMap()
     );
@@ -3029,20 +3023,17 @@ int main(int argc, char *argv[])
                 {
                     auto oldHandler = fileOperation::fileHandler(writeHandler);
 
-                    IOmapDistributePolyMeshRef
+                    IOmapDistributePolyMesh::writeContents
                     (
                         IOobject
                         (
                             "procAddressing",
                             areaProcMeshPtr->facesInstance(),
                             faMesh::meshSubDir,
-                            areaProcMeshPtr->thisDb(),
-                            IOobjectOption::NO_READ,
-                            IOobjectOption::NO_WRITE,
-                            IOobjectOption::NO_REGISTER
+                            areaProcMeshPtr->thisDb()
                         ),
                         faDistMap
-                    ).write();
+                    );
 
                     areaProcMeshPtr->write();
 
diff --git a/src/OpenFOAM/db/IOobjects/IOList/IOList.C b/src/OpenFOAM/db/IOobjects/IOList/IOList.C
index a6a0bbb200..1e535c861d 100644
--- a/src/OpenFOAM/db/IOobjects/IOList/IOList.C
+++ b/src/OpenFOAM/db/IOobjects/IOList/IOList.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2016-2024 OpenCFD Ltd.
+    Copyright (C) 2016-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -118,7 +118,7 @@ template<class T>
 Foam::IOListRef<T>::IOListRef
 (
     const IOobject& io,
-    const List<T>& content
+    const UList<T>& content
 )
 :
     regIOobject(io),
@@ -143,6 +143,23 @@ Foam::List<T> Foam::IOList<T>::readContents(const IOobject& io)
 }
 
 
+template<class T>
+void Foam::IOList<T>::writeContents
+(
+    const IOobject& io,
+    const UList<T>& content
+)
+{
+    IOListRef<T> writer
+    (
+        IOobject(io, IOobjectOption::NO_REGISTER),
+        content
+    );
+
+    writer.write();
+}
+
+
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 template<class T>
@@ -156,7 +173,7 @@ bool Foam::IOList<T>::writeData(Ostream& os) const
 template<class T>
 bool Foam::IOListRef<T>::writeData(Ostream& os) const
 {
-    os << contentRef_.cref();
+    os << contentRef_;
     return os.good();
 }
 
diff --git a/src/OpenFOAM/db/IOobjects/IOList/IOList.H b/src/OpenFOAM/db/IOobjects/IOList/IOList.H
index 636fab73db..40f62c6d03 100644
--- a/src/OpenFOAM/db/IOobjects/IOList/IOList.H
+++ b/src/OpenFOAM/db/IOobjects/IOList/IOList.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2018-2024 OpenCFD Ltd.
+    Copyright (C) 2018-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -96,6 +96,10 @@ public:
         //- Read and return contents. The IOobject is never registered
         static List<T> readContents(const IOobject& io);
 
+        //- Write contents. The IOobject is never registered.
+        //  Uses IOListRef internally.
+        static void writeContents(const IOobject& io, const UList<T>& content);
+
 
     //- Destructor
     virtual ~IOList() = default;
@@ -121,7 +125,7 @@ public:
                           Class IOListRef Declaration
 \*---------------------------------------------------------------------------*/
 
-//- A IOList wrapper for writing external data.
+//- A IOList wrapper for writing external List data
 template<class T>
 class IOListRef
 :
@@ -130,7 +134,7 @@ class IOListRef
     // Private Data
 
         //- Reference to the external content
-        refPtr<List<T>> contentRef_;
+        UList<T> contentRef_;
 
 
 public:
@@ -161,7 +165,7 @@ public:
     // Constructors
 
         //- Construct from IOobject and const data reference
-        IOListRef(const IOobject& io, const List<T>& content);
+        IOListRef(const IOobject& io, const UList<T>& content);
 
 
     //- Destructor
@@ -171,10 +175,9 @@ public:
     // Member Functions
 
         //- Allow cast to const content
-        //  Fatal if content is not set
-        operator const List<T>&() const
+        operator const UList<T>&() const
         {
-            return contentRef_.cref();
+            return contentRef_;
         }
 
         //- The writeData method for regIOobject write operation
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.C b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.C
index 8f35bbedaa..0557a63f54 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.C
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2015 OpenFOAM Foundation
-    Copyright (C) 2022-2024 OpenCFD Ltd.
+    Copyright (C) 2022-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -124,6 +124,23 @@ Foam::IOmapDistributePolyMeshRef::IOmapDistributePolyMeshRef
 ///     contentRef_.ref(map);  // writable reference
 /// }
 
+// * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
+
+void Foam::IOmapDistributePolyMesh::writeContents
+(
+    const IOobject& io,
+    const mapDistributePolyMesh& map
+)
+{
+    IOmapDistributePolyMeshRef writer
+    (
+        IOobject(io, IOobjectOption::NO_REGISTER),
+        map
+    );
+
+    writer.write();
+}
+
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
diff --git a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.H b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.H
index b0d85a2afd..92fb1390c6 100644
--- a/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.H
+++ b/src/OpenFOAM/meshes/polyMesh/mapPolyMesh/mapDistribute/IOmapDistributePolyMesh.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2015 OpenFOAM Foundation
-    Copyright (C) 2022-2024 OpenCFD Ltd.
+    Copyright (C) 2022-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -88,6 +88,17 @@ public:
         );
 
 
+    // Factory Methods
+
+        //- Write contents. The IOobject is never registered.
+        //  Uses IOmapDistributePolyMeshRef internally.
+        static void writeContents
+        (
+            const IOobject& io,
+            const mapDistributePolyMesh& map
+        );
+
+
     //- Destructor
     virtual ~IOmapDistributePolyMesh() = default;
 
diff --git a/src/conversion/ccm/reader/ccmReader.H b/src/conversion/ccm/reader/ccmReader.H
index 147c320a4d..ab05dc2c0e 100644
--- a/src/conversion/ccm/reader/ccmReader.H
+++ b/src/conversion/ccm/reader/ccmReader.H
@@ -393,7 +393,7 @@ private:
         (
             const objectRegistry& registry,
             const word& propertyName,
-            const labelList& list,
+            const labelUList& list,
             IOstreamOption streamOpt
         ) const;
 
diff --git a/src/conversion/ccm/reader/ccmReaderAux.C b/src/conversion/ccm/reader/ccmReaderAux.C
index 3e119be25c..eb5167095a 100644
--- a/src/conversion/ccm/reader/ccmReaderAux.C
+++ b/src/conversion/ccm/reader/ccmReaderAux.C
@@ -145,7 +145,7 @@ void Foam::ccm::reader::writeMeshLabelList
 (
     const objectRegistry& registry,
     const word& propertyName,
-    const labelList& list,
+    const labelUList& list,
     IOstreamOption streamOpt
 ) const
 {
diff --git a/src/conversion/common/reader/meshReader.H b/src/conversion/common/reader/meshReader.H
index 68baf6a775..3bd02e90bc 100644
--- a/src/conversion/common/reader/meshReader.H
+++ b/src/conversion/common/reader/meshReader.H
@@ -192,7 +192,7 @@ private:
         (
             const objectRegistry& registry,
             const word& propertyName,
-            const labelList& list,
+            const labelUList& list,
             IOstreamOption streamOpt
         ) const;
 
diff --git a/src/conversion/common/reader/meshReaderAux.C b/src/conversion/common/reader/meshReaderAux.C
index d4b4d5f426..bdf234e949 100644
--- a/src/conversion/common/reader/meshReaderAux.C
+++ b/src/conversion/common/reader/meshReaderAux.C
@@ -108,7 +108,7 @@ void Foam::meshReader::writeMeshLabelList
 (
     const objectRegistry& registry,
     const word& propertyName,
-    const labelList& list,
+    const labelUList& list,
     IOstreamOption streamOpt
 ) const
 {
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
index 78bb1bfe48..e3f66c3503 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.C
@@ -101,8 +101,8 @@ Foam::hexRef8Data::hexRef8Data
 (
     const IOobject& io,
     const hexRef8Data& data,
-    const labelList& cellMap,
-    const labelList& pointMap
+    const labelUList& cellMap,
+    const labelUList& pointMap
 )
 {
     if (data.cellLevelPtr_)
diff --git a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.H b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.H
index 8363c3839a..9e5b4706f6 100644
--- a/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.H
+++ b/src/dynamicMesh/polyTopoChange/polyTopoChange/hexRef8/hexRef8Data.H
@@ -93,8 +93,8 @@ public:
         (
             const IOobject& io,
             const hexRef8Data&,
-            const labelList& cellMap,
-            const labelList& pointMap
+            const labelUList& cellMap,
+            const labelUList& pointMap
         );
 
         //- Construct from multiple hexRef8Data
diff --git a/src/parallel/decompose/faDecompose/faMeshDecomposition.C b/src/parallel/decompose/faDecompose/faMeshDecomposition.C
index 006b556e5a..6380659279 100644
--- a/src/parallel/decompose/faDecompose/faMeshDecomposition.C
+++ b/src/parallel/decompose/faDecompose/faMeshDecomposition.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2016-2017 Wikki Ltd
-    Copyright (C) 2018-2024 OpenCFD Ltd.
+    Copyright (C) 2018-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -1318,19 +1318,19 @@ bool Foam::faMeshDecomposition::writeDecomposition()
 
         // pointProcAddressing
         ioAddr.rename("pointProcAddressing");
-        IOListRef<label>(ioAddr, procPatchPointAddressing_[procI]).write();
+        IOList<label>::writeContents(ioAddr, procPatchPointAddressing_[procI]);
 
         // edgeProcAddressing
         ioAddr.rename("edgeProcAddressing");
-        IOListRef<label>(ioAddr, procEdgeAddressing_[procI]).write();
+        IOList<label>::writeContents(ioAddr, procEdgeAddressing_[procI]);
 
         // faceProcAddressing
         ioAddr.rename("faceProcAddressing");
-        IOListRef<label>(ioAddr, procFaceAddressing_[procI]).write();
+        IOList<label>::writeContents(ioAddr, procFaceAddressing_[procI]);
 
         // boundaryProcAddressing
         ioAddr.rename("boundaryProcAddressing");
-        IOListRef<label>(ioAddr, procBoundaryAddressing_[procI]).write();
+        IOList<label>::writeContents(ioAddr, procBoundaryAddressing_[procI]);
     }
 
 
diff --git a/src/parallel/reconstruct/faReconstruct/faMeshReconstructor.C b/src/parallel/reconstruct/faReconstruct/faMeshReconstructor.C
index 4f6002839d..8786ffb395 100644
--- a/src/parallel/reconstruct/faReconstruct/faMeshReconstructor.C
+++ b/src/parallel/reconstruct/faReconstruct/faMeshReconstructor.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2021-2024 OpenCFD Ltd.
+    Copyright (C) 2021-2025 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -693,19 +693,19 @@ void Foam::faMeshReconstructor::writeAddressing
 
     // boundaryProcAddressing
     ioAddr.rename("boundaryProcAddressing");
-    IOListRef<label>(ioAddr, faBoundaryProcAddr).write();
+    IOList<label>::writeContents(ioAddr, faBoundaryProcAddr);
 
     // faceProcAddressing
     ioAddr.rename("faceProcAddressing");
-    IOListRef<label>(ioAddr, faFaceProcAddr).write();
+    IOList<label>::writeContents(ioAddr, faFaceProcAddr);
 
     // pointProcAddressing
     ioAddr.rename("pointProcAddressing");
-    IOListRef<label>(ioAddr, faPointProcAddr).write();
+    IOList<label>::writeContents(ioAddr, faPointProcAddr);
 
     // edgeProcAddressing
     ioAddr.rename("edgeProcAddressing");
-    IOListRef<label>(ioAddr, faEdgeProcAddr).write();
+    IOList<label>::writeContents(ioAddr, faEdgeProcAddr);
 }
 
 
@@ -760,7 +760,7 @@ void Foam::faMeshReconstructor::writeMesh
         IOobject io(fullMesh.boundary());
 
         io.rename("faceLabels");
-        IOListRef<label>(io, singlePatchFaceLabels).write();
+        IOList<label>::writeContents(io, singlePatchFaceLabels);
 
         fullMesh.boundary().write();