A.John Evans, codes and standards manager with Icynene, responds: Most building codes require that foam plastic insulation — including both rigid and open-cell low-density foam products — be separated from occupied living space (including basements) by an approved 15-minute thermal barrier.

While 1/2-inch gypsum board is recognized for this purpose by most codes, other less-common materials that can be used are sprayed-on cementitious coatings (A/D Fire Protection Systems, www.adfire.com ) and mineral-fiber coatings (American Sprayed Fibers, www.asfiusa.com). Before using a system not specifically mentioned by code, of course, it's...

or Register to read the full article.