The Construction Specifier, Jan. 2014, by Jared O. Blum.
http://www.kenilworth.com/publications/cs/de/201401/index.html and click or scroll to page 66.

"In response to a national interest in, and policies for, conservation of energy, model energy codes are striving to advance the way commercial and residential building envelopes are insulated. The effect on how design professionals specify materials for thermal management will be substantial."