Have 3 Cotton Patch goslings in the brooder & need to build a coop. Any designs appreciated. The simpler the better as I will be building this myself. I've read they need 8sf per goose & I plan on getting a 4th next Spring. So far I'm planning on 6' x 5 1/2', elevated 12-18" off the ground (we get a LOT of water in Spring). Do they need heat? We get down to -20F to -30F in Winter. They free range during the day. TIA.