The contractor paid for some of the material, so I don't have a receipt to look back on except his, and on his receipt he calls it Zip Roof. It was supposed to be waterproof for 90 days after it was installed and taped. They used air to clean all the seams before taping. Contractor had seen some on a roof longer than the 90 days without any problems. Another advantage was they didn't have to use tar paper with it.
About all I really know about the foam insulation was that it's biodegradable and non toxic. The insulating contractor worked around the outsides first without the ceiling sheetrocked. This gave him easy access to where the biggest loss of air was possible, where the ceiling and wall join. After working the edges up to where they were high enough to get to in the attic, the ceiling sheet rock went up. This was so he didn't have to worry as much about splatter and dripping. The wall between the garage and house is fully insulated from floor to roof. Masonite was used as backing in the attic from the ceiling to the roof there and around the porch above the main walls. Went ahead and fully insulated garage roof, especially since the walls all around it were the foam block. Unless we leave open a garage door they expect the garage to stay around 45 degrees. Hope so as I put a sink in the garage. Did you notice the truss rafters were on 16" centers and hurricane strapped down? I also had them use anchored porch posts. Figured the porch overhang would be where the wind would get under the roof at, so it's anchored with the posts also.
