diff --git a/lib/to_openstudio/geometry/face.rb b/lib/to_openstudio/geometry/face.rb
index e153bd4..86daec1 100644
--- a/lib/to_openstudio/geometry/face.rb
+++ b/lib/to_openstudio/geometry/face.rb
@@ -207,7 +207,7 @@ def to_openstudio(openstudio_model)
       os_surface
     end
 
-    def to_openstudio_shade(openstudio_model, shading_surface_group)
+    def to_openstudio_shade(openstudio_model)
       # get the vertices from the face
       if @hash[:geometry][:vertices].nil?
         hb_verts = @hash[:geometry][:boundary]