Here is a really nice brooder on the brooder and incubator forum:
https://www.backyardchickens.com/articles/amferro103s-homemade-chicken-brooder.47990/cover-image
Here is the incubator and brooder thread to look at:
https://www.backyardchickens.com/articles/categories/incubators-brooders.27/
https://www.backyardchickens.com/articles/amferro103s-homemade-chicken-brooder.47990/cover-image
Here is the incubator and brooder thread to look at:
https://www.backyardchickens.com/articles/categories/incubators-brooders.27/