I've never seen that mat material, thanks! It's still a bit pricey for me to use, I think. I might do that if the coop had been the size I originally planned, but DH had bigger ideas. This coop is already costing more than I wanted it to, though at the price of a gallon of gas and the gas-sucking properties of our pickup truck we haul materials in, it's not going to save us anything to run around looking for free stuff. Home construction is down or we might be able to get stuff at log home sites like we have in the past, though we can't get full size 2x4s and full sheets of plywood like we needed at dumpsters.
DH got lots of trim pieces and stuff to cover the vents with (aluminum gutter guards work great), so after he has a new exhaust installed on his truck tomorrow, we may be able to get more done, weather permitting.