diff --git a/src/ifcconvert/IfcConvert.cpp b/src/ifcconvert/IfcConvert.cpp
index c3eb82e2c9..f5f6c44346 100644
--- a/src/ifcconvert/IfcConvert.cpp
+++ b/src/ifcconvert/IfcConvert.cpp
@@ -737,6 +737,7 @@ int main(int argc, char** argv) {
 
 	if (vmap.count("force-space-transparency")) {
 		settings.force_space_transparency(force_space_transparency);
+		IfcGeom::update_default_style("IfcSpace").Transparency().reset(force_space_transparency);
 	}
 
 	boost::shared_ptr<GeometrySerializer> serializer; /**< @todo use std::unique_ptr when possible */
diff --git a/src/ifcgeom_schema_agnostic/IfcGeomRenderStyles.h b/src/ifcgeom_schema_agnostic/IfcGeomRenderStyles.h
index 2154fe24b4..33971f7182 100644
--- a/src/ifcgeom_schema_agnostic/IfcGeomRenderStyles.h
+++ b/src/ifcgeom_schema_agnostic/IfcGeomRenderStyles.h
@@ -96,7 +96,10 @@ namespace IfcGeom {
 		boost::optional<double>& Specularity() { return specularity; }
 	};
 
-  IFC_GEOM_API const SurfaceStyle* get_default_style(const std::string& ifc_type);
+	IFC_GEOM_API const SurfaceStyle* get_default_style(const std::string& ifc_type);
+
+	IFC_GEOM_API SurfaceStyle& update_default_style(const std::string& ifc_type);
+
 	IFC_GEOM_API void set_default_style_file(const std::string& json_file);
 }
 
diff --git a/src/ifcgeom_schema_agnostic/SurfaceStyle.cpp b/src/ifcgeom_schema_agnostic/SurfaceStyle.cpp
index 10c2335ff3..6760b20a6d 100644
--- a/src/ifcgeom_schema_agnostic/SurfaceStyle.cpp
+++ b/src/ifcgeom_schema_agnostic/SurfaceStyle.cpp
@@ -43,6 +43,10 @@ void InitDefaultMaterials() {
 	default_materials.insert(std::make_pair("IfcPlate", IfcGeom::SurfaceStyle("IfcPlate")));
 	default_materials["IfcPlate"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.8, 0.8, 0.8));
 
+	default_materials.insert(std::make_pair("IfcSpace", IfcGeom::SurfaceStyle("IfcSpace")));
+	default_materials["IfcWindow"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.65, 0.75, 0.8));
+	default_materials["IfcWindow"].Transparency().reset(0.8);
+
 	default_material = IfcGeom::SurfaceStyle("DefaultMaterial");
 	default_material.Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.7, 0.7, 0.7));
 
@@ -121,3 +125,12 @@ const IfcGeom::SurfaceStyle* IfcGeom::get_default_style(const std::string& s) {
 	const IfcGeom::SurfaceStyle& surface_style = it->second;
 	return &surface_style;
 }
+
+IfcGeom::SurfaceStyle& IfcGeom::update_default_style(const std::string& s) {
+	if (!default_materials_initialized) InitDefaultMaterials();
+	std::map<std::string, IfcGeom::SurfaceStyle>::iterator it = default_materials.find(s);
+	if (it == default_materials.end()) {
+		throw std::runtime_error("No style registered for " + s);
+	}
+	return it->second;
+}