Searching the Internet, unable to find clear information on toxic smoke hazards of rigid foam boards, but best appears to be polyethylene, but can't find a U.S. supplier. Best I could find was an Australian company at www. thermotec.com, the Thermotec company. My search engines gave me mostly suppliers of polystyrene, not poly- ethylene. Can anyone help? Apparently the PE board also offers little emissions of HFCs, so it is environmentally better than some other boards. I want to insulate the garage door with something light in weight, easy to apply, and relatively benign if overheated.