Application of intumescent and vapor retarder coatings on open-cell spray polyurethane insulation

Abstract

A method of providing fire protection and vapor transmission resistance to a polyurethane foam insulation material, comprising: spraying an open cell polyurethane foam insulation onto a building structure; applying an intumescent paint onto the open cell polyurethane foam insulation; and then applying a vapor retarder paint over the intumescent paint. The vapor retarder paint may be a latex or styrene-butadiene rubber based paint, and the intumescent paint may be made of a water based acrylic or vinyl acetate copolymer and may have chemical additives that react to heat by swelling to generate a heat-insulating char layer that slows or prevents flame propagation.

Dependencies are inferred from the claim text.