Thermasheath®-SI is a composite product made up of energy-efficient insulation and a structural component and is designed to work seamlessly with non-structural Rmax Thermasheath®-3. The insulation component is a closed-cell polyiso foam bonded to reflective, reinforced aluminum facers. The structural component is a board made up of pressure laminated plies of cellulosic fibers specially treated with a water-resistant adhesive.
Thermasheath®-SI is suitable for use in residential wood stud construction. Furthermore, with 1/2" interior gypsum, it is designed to be a one-to-one substitute for wood sheathing in shear wall resistance.