diff --git a/src/ifcgeomserver/IfcGeomServer.cpp b/src/ifcgeomserver/IfcGeomServer.cpp
index 03850784ce..e15d888f2b 100644
--- a/src/ifcgeomserver/IfcGeomServer.cpp
+++ b/src/ifcgeomserver/IfcGeomServer.cpp
@@ -240,7 +240,12 @@ protected:
 			   0,    0,    0,     1
 		};
 		swrite(s, std::string((char*)matrix_array, 16 * sizeof(float)));
-		swrite<int32_t>(s, geom->geometry().id());
+		
+		// The first bit of the string is always the instance name of the representation.
+		const std::string& representation_id = geom->geometry().id();
+		const int integer_representation_id = atoi(representation_id.c_str());
+		swrite<int32_t>(s, (int32_t)integer_representation_id);
+
 		swrite(s, std::string((char*)geom->geometry().verts().data(), geom->geometry().verts().size() * sizeof(float)));
 		swrite(s, std::string((char*)geom->geometry().normals().data(), geom->geometry().normals().size() * sizeof(float)));
 		{
diff --git a/src/ifcwrap/IfcGeomWrapper.i b/src/ifcwrap/IfcGeomWrapper.i
index f6870770ae..01fbc575ac 100644
--- a/src/ifcwrap/IfcGeomWrapper.i
+++ b/src/ifcwrap/IfcGeomWrapper.i
@@ -374,7 +374,7 @@ struct ShapeRTTI : public boost::static_visitor<PyObject*>
 					IfcGeom::IfcRepresentationShapeItems shapes;
 					if (kernel.convert_shapes(instance, shapes)) {
 						IfcGeom::ElementSettings element_settings(settings, kernel.getValue(IfcGeom::Kernel::GV_LENGTH_UNIT), IfcSchema::Type::ToString(instance->type()));
-						IfcGeom::Representation::BRep brep(element_settings, instance->entity->id(), shapes);
+						IfcGeom::Representation::BRep brep(element_settings, boost::lexical_cast<std::string>(instance->entity->id()), shapes);
 						try {
 							if (settings.get(IfcGeom::IteratorSettings::USE_BREP_DATA)) {
 								return new IfcGeom::Representation::Serialization(brep);