Fire hazard of foil faced polyiso exposed to Ceiling interior?

Hi,I would like to sandwich a 1/2″ layer of foil faced poly iso between the bottom chord of a ceiling/floor truss and 1/2″ gypsum. I have attached a diagram. The… Hi,I would like to sandwich a 1/2″ layer of foil faced poly iso between the bottom chord of a ceiling/floor truss and 1/2″ gypsum. I have attached a diagram. The…Read MoreGreenBuildingAdvisor