I drew a building that has a shading device by using Rhino and Grasshopper. The entire body is drawn by Rhino except the louvers of shading device (Mashrabiya) is drawn by Grasshopper. I used for simulation DIVA twice; one with the Mashrabiya DIand another with not. I got similar results!! How could I assign the Mashrabiya as a shading device? Please any advice!

Thanks in advance,