Foam sheathing board is Johns Manville’s answer to the demand for continuous insulation solutions that meet increasingly stringent energy-efficiency code standards. Made from a uniform closed-cell polyisocyanurate foam core, JM offers three foam board products that are lightweight, non-corrosive and easy to handle and cut. With R-values up to R-25 at a thickness of 4 inches, JM foam board offers an efficient way to dramatically increase the overall thermal efficiency of walls and roofs.
Manufactured to use advanced blowing agents, JM foam board meets the latest environmental regulations, and works well with all other types of JM high-performance commercial and residential products. It can be used in both new and retrofit construction, including interior and exterior insulation, as well as roof decks. And its range of possible uses includes masonry cavity walls, below-grade basement walls, crawlspaces, framed walls (wood and metal), pre-engineered metal buildings, and cathedral and flat ceilings.