I've been given a roll of tar paper and told I should wrap my coop (sides and roof) in it before I put the siding. Right now, the coop is a shell of 2x4's with no plywood or anything. With the tar paper installed and the siding (which is re-used boards from an old barn), the coop will be fine and the chickens will be well insulated. Is this correct? Most of the other coops I've seen and read about on this site seem to have plywood put up before anything else - siding, tar paper, etc... What is recommended to ensure the chickens are well protected / insulated?