The excavation outside the foundation shall be backfilled with soil that is free of organic material, construction debris, cobbles and boulders or with a controlled low-strength material (CLSM).  

  Keeping up with changes to codes and standards is increasingly complex. 

The advancement of the levels of insulation matches the awareness and activities taking place, not just in the United States, but across North America and the world. 

 11506.3 Material specifications and physical characteristics. Roof-covering materials shall conform to the applicable standards listed in this chapter.  

 Sustainable roofing systems can be many things, but primarily they are assemblies that provide a covering protecting a building from the elements (i.e., water, sun, cold, and heat) while minimizing their burden on the environment and conserving energy.