diff --git a/src/ifcconvert/IgesSerializer.h b/src/ifcconvert/IgesSerializer.h
index 8591af9902..fccb0a09f1 100644
--- a/src/ifcconvert/IgesSerializer.h
+++ b/src/ifcconvert/IgesSerializer.h
@@ -46,6 +46,7 @@ public:
 	void setUnitNameAndMagnitude(const std::string& name, float magnitude) {
 		const char* symbol = getSymbolForUnitMagnitude(magnitude);
 		if (symbol) {
+			Interface_Static::SetCVal("xstep.cascade.unit", symbol);
 			Interface_Static::SetCVal("write.iges.unit", symbol);
 		}
 	}
diff --git a/src/ifcconvert/OpenCascadeBasedSerializer.cpp b/src/ifcconvert/OpenCascadeBasedSerializer.cpp
index 3dc8ad9386..2dbb642c3d 100644
--- a/src/ifcconvert/OpenCascadeBasedSerializer.cpp
+++ b/src/ifcconvert/OpenCascadeBasedSerializer.cpp
@@ -42,6 +42,12 @@ void OpenCascadeBasedSerializer::write(const IfcGeom::BRepElement<double>* o) {
 
 		const gp_Trsf& o_trsf = o->transformation().data();
 		gtrsf.PreMultiply(o_trsf);
+
+		if (o->geometry().settings().convert_back_units()) {
+			gp_Trsf scale;
+			scale.SetScaleFactor(1.0 / o->geometry().settings().unit_magnitude());
+			gtrsf.PreMultiply(scale);
+		}
 		
 		const TopoDS_Shape& s = it->Shape();			
 			
diff --git a/src/ifcconvert/StepSerializer.h b/src/ifcconvert/StepSerializer.h
index 4667104a38..9d8ca7b211 100644
--- a/src/ifcconvert/StepSerializer.h
+++ b/src/ifcconvert/StepSerializer.h
@@ -52,6 +52,7 @@ public:
 	void setUnitNameAndMagnitude(const std::string& name, float magnitude) {
 		const char* symbol = getSymbolForUnitMagnitude(magnitude);
 		if (symbol) {
+			Interface_Static::SetCVal("xstep.cascade.unit", symbol);
 			Interface_Static::SetCVal("write.step.unit", symbol);
 		}
 	}