diff --git a/src/ifcparse/IfcWrite.cpp b/src/ifcparse/IfcWrite.cpp
index 4ff08eec48..2adabed7f8 100644
--- a/src/ifcparse/IfcWrite.cpp
+++ b/src/ifcparse/IfcWrite.cpp
@@ -289,9 +289,9 @@ void IfcWriteArgument::set(const aggregate_of_aggregate_of_instance::ptr& v) {
 }
 
 // Overload to detect null values
-void IfcWriteArgument::set(IfcUtil::IfcBaseClass*const& v) {
+void IfcWriteArgument::set(IfcUtil::IfcBaseInterface*const& v) {
 	if (v) {
-		container = v;
+		container = v->as<IfcUtil::IfcBaseClass>();
 	} else {
 		container = boost::blank();
 	}
diff --git a/src/ifcparse/IfcWrite.h b/src/ifcparse/IfcWrite.h
index 502ec21f1e..c69ca6052b 100644
--- a/src/ifcparse/IfcWrite.h
+++ b/src/ifcparse/IfcWrite.h
@@ -129,7 +129,7 @@ namespace IfcWrite {
 		}
 
 		template <typename T>
-		typename boost::disable_if<boost::is_base_of<IfcUtil::IfcBaseClass, typename boost::remove_pointer<T>::type>, void>::type
+		typename boost::disable_if<boost::is_base_of<IfcUtil::IfcBaseInterface, typename boost::remove_pointer<T>::type>, void>::type
 		set(const T& t) {
 			container = t;
 		}
@@ -141,7 +141,7 @@ namespace IfcWrite {
 		void set(const aggregate_of_aggregate_of_instance::ptr& v);
 
 		// Overload to detect null values
-		void set(IfcUtil::IfcBaseClass*const & v);
+		void set(IfcUtil::IfcBaseInterface*const & v);
 		
 		operator int() const;
 		operator bool() const;