CertainTeed Corp., Valley Forge, Pa., has introduced OPTIMA, a fiber glass insulation designed for the blow-in system for use in new construction closed-cavity applications such as cathedral ceilings. The product consists of two components – insulation and non-woven fabric — and is blown-in without any additives. When installed at recommended density levels, the insulation is designed to yield an R-15 in 2- by 4-inch construction and R-23 in 2- by 6-inch construction.