Save up to %50 on your energy bills with Icynene Custom Insulation. Icynene®, the leading soft foam insulation and air barrier system, is becoming the industry standard for providing maximum building envelope performance. Applied as a liquid, Icynene® expands to 100 times its volume in seconds to fill every crack and crevice while remaining flexible so that the integrity of the building envelope seal remains intact over time. Icynene's spray formula has an R-value of 3.6 per inch. It acts as a complete insulation and air barrier to minimize air leakage and seal the building envelope for optimal airtightness.