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.
The year 2011 saw the Department of Homeland Security and the Social Security Administration taking an increasingly aggressive stance in using all available information to curb the hiring of unauthorized workers and to penalize employers who do.