I built a smallish coop, about 4'x8', out of insulated board. There is a guy in Thorndike, ME who makes it. What it is is two sheets of Pressed board, you know the plywood looking stuff that is all chips glued together, with that pink insulation board in between. The stuff is about 6" thick and comes in 4'x8' sections. I did use regular press board for the peak and roof and sealed that up with the tube gel, Geoseal. I know this spring when it was chilly out it was toasty in there. I don't know how much the stuff costs as I got it from a guy who had it left over from building his house. I love Free Cycle! He said it is something like R30 for insulation.
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