So I'm cleaning the brooder today so the lid is off. I turned around and my ten day old EE is perched up on the side of the brooder that is at least two feet high! WOW they grow up fast.
and You've come to the right place. There is a ton of information on coops here. I recommend doing a fair bit of research before you build. You can do a search for coop construction or check out the learning center on the BYC main page. That is where I got a lot of my ideas.