This is a picture of my outside brooder. It has only been 22 as a low here so far, but they were toasty. I used plastic and an old shower curtain liner. The run they are in is surrounded with plastic on the open areas in an outside shed. They have a heat lamp. The ones in there now are 3 weeks old and have been out about 2 weeks. I keep them in the house for first week with a heat plate.