Polyurethane foam is really a great invention. Now that I am more informed about SPF foam I think I would use it on my home for insulation, especially if I ever moved to a cold northern area. I am guessing the doctor saved a lot of money by getting polyurethane spray foam insulation during construction. Filling the walls afterwards would probably require a lot of tearing down and rebuilding type work. I’ve heard icynene foam (icynene sounds like a spin-off of theoretical ice-9 solid water sci fi name maybe?) can be poured. I’ve heard some contractors just poke a hole in hard to reach places and fill the walls with icynene foam. I think I’ve heard icynene foam is based on castor oil. This is truly even more strange than soy-based foam. I suppose being even greener doesnt hurt as long as these types of foam don’t cost a lot of extra money. Reply
Why can’t I find anything about whether you can use this material for roofing where there are heavy snow loads. I am interested in lightening the roof load. Reply
I am looking for how to reduce load on a Colorado roof I can’t find anything about snow loads with this material Reply
Regarding snow load, the closed cell spray polyurethane foam we use in roofing applications is rated to support 40 psi. In other words, the foam roof system will support a snow load of up to 5760 psf! Even Antarctic conditions do not have snow loads anywhere close to this high. For example, 100 psf is a very high snow load. In any case, beams and deck boards will fail under an unusually heavy snow load long before the roof material. Thus, you have no need to worry about snow loads as far as foam roofing materials are concerned. I’m aware of RIM “Roof Ice Melt” systems which are installed at the perimeter of sloped roofs. A manufacturer of this product may be able to recommend a system for melting snow over more expansive roof areas where you want to reduce snow load. Reply
I am also interested in insulating a roof in a cold climate, but the limited research I have done so far says you can’t use SPF at 50 psf or higher snow loads – that you need a vented roof. The justification I saw was that the insulation of the deeper snow on the roof with these higher snow loads is more prone to cause ice damming. Reply