Core Materials

The core material of SIPs used in wall construction shall be composed of molded expanded polystyrene (EPS) meeting the requirements of ASTM C 578, type I, with minimum density of 0.90 lb/ft3 (14.42 kg/m2), or an approved alternate. Flamespread rating of SIP cores shall be less than 75 and the smoke-development rating shall be less than 450, as tested in accordance with ASTM E 84. The minimum thickness of the core for SIP walls shall be 3.5 inches (89 mm). SIP core insulation shall bear a label containing the following as a minimum:

• Manufacturer identification,
• Product standard and type,
• Flame-spread/smoke-developed,
• Name, logo or identification of quality assurance agency.