May 29, 2011 by: Eric Mac Inerney

Solar Shade Study, Study vs Real
Real vs. Study Shot of the Solar Shading on May 28 at 3:00

     Part of designing green buildings, whether it be residential design or commercial design, is properly shading the windows so that you let the sun's heat in when you want it and block it when you don't.  Fortunately (or not, as we have already hit 100° this summer), in the Texas climate, it is mostly a battle to shade the windows.  
The computer's ability to model not just the building, but shadows and lights, has become a great tool for looking at solar shading. Rather than creating complicated graphs and maps to calculate the astral projection of the sun's rays, we can now simply orient our model and tell the computer where the building is and enter the time and date you want to study.
     Here are two examples.  In the above pictures, I have shown the solar study and the actual building at about the same date and time.  Below, I am showing an animation looking at an entire day.  In both cases, you can see that the large porches and the projecting garage protect all the main windows from the sun.
     One of the things we used this model for was to look at the windows in the bump-out above the garage.  By extending the overhang further into the setback, we were able to provide much better shading.  The Austin code allows solar shading devices to extend further into setbacks -- and this model is how we proved ours was worthy of the exemption.
     If you're designing a green building, ask your architect to run a solar study on your plans.  A few tweaks can make a huge difference in your green design -- and your future utility bills!

Residential Design & Construction/ Architects and Construction/ Sustainable Design