diff --git a/src/ifcgeom/mapping/IfcVector.cpp b/src/ifcgeom/mapping/IfcVector.cpp
index c88e22a774..04ac6474cc 100644
--- a/src/ifcgeom/mapping/IfcVector.cpp
+++ b/src/ifcgeom/mapping/IfcVector.cpp
@@ -23,6 +23,7 @@ using namespace ifcopenshell::geometry;
 
 taxonomy::ptr mapping::map_impl(const IfcSchema::IfcVector* inst) {
 	auto d = taxonomy::cast<taxonomy::direction3>(map(inst->Orientation()));
+	d = taxonomy::direction3::ptr(d->clone_());
 	d->components() *= inst->Magnitude() * length_unit_;
 	return d;
 }