I'm building a brooder with the measurements 3' wide by 3' high, by 5' long, with a frame already built of 2x2 pine. It feels a little rickety, but DBF assures me it'll get more solid when we add walls. We picked up some 2x6's and had them cut to 5' to put on the front and back, but I'm thinking they need some sort of insulation to go with them. The ends of the brooder are going to be recycled plywood and will be doors on both ends. Any ideas?