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[Janie Sutton]

There have been some instances where contractors who serve states adjacent to North Carolina are being supplied with foam plastic insulation for ductwork that does not meet section 604.3 and 604.4. The IRC has a less restrictive requirement and they are under the impression that this is also allowed in North Carolina. The North Carolina Codes require a flame spread index of not more than 25 and smoke developed index of not more than 50 in accordance with ASTM E 84.