3-1/2 in. x 4 ft. x 8 ft. Rmax Insulation R23.9

Rmax rigid insulation is a high-performance polyiso solution engineered to deliver superior thermal efficiency, moisture resistance, and long-term durability. With one of the highest R-values per inch in the industry, Rmax helps reduce energy costs while simplifying installation with continuous insulation that meets modern building codes. Designed for walls, roofs, and specialty applications, it provides a smarter, more efficient building envelope