Polyurea (PUA) foam, the product of a reaction between polymeric MDI and water, has been developed as a new retrofit insulation material. PUA foam has demonstrated commercially acceptable physical and fire properties. Studies of local temperature build-up around electric circuitry embedded in PUA foam in dicate that heat build-up presents no problem in or around conductors and switch and outlet boxes. A study of fuel consumption in houses retrofitted with PUA foam indicate fuel savings of up to 50 percent due to its insulation proper ties.