We built a straw coop last fall for our chickens. It held up really well and kept our girls cozy-warm in our frigid VT winter. I will get some pics when it is a little brighter out.
Basically we followed the design in Andy Lee's Chicken Tractor. We made the floor out of pallets, put a metal roof on four posts and the walls are bales. We had to frame a door and we used rebar and posts to reinforce the walls. We used an old interior door for the door and cut a hole in it for a window. an
While there are some things I would tweak, it was a fun project and has proven to be much more durable than I thought it would be. In fact, I plan to use it again this year for the bantam chicks I have in the brooder.
Things I plan to change:
1. The floor. While the pallets are a good foundation, I would like to put playwood over the top to help reduce drafts and make it easier to clean/shovel.
2. Overventilated. We left about 6" open on three side of the coop between the top of the bales and the roof for ventilation. I found this to be too much for the coldest part of the winter and wound up patching up with loose hay to keep out the bitter cold winds. We did use old welded wire fencing to wrap around this opening and secured it to the roof supports to keep out wild birds, etc. I'll also devise some sort of cover to put over the "window " (read hole covered w/chicken wire) in the door to keep out wind/drafts.
I would also like to make it somewhat more predator proof. We have a fox around here but he has never attempted to get into the coop as far as I can tell. The pallet floor means that we're pretty safe from digging predators. So far we 've never had raccoon issues, but it would be pretty easy for them to get in if they really wanted to.
I can say that I am extremely satisfied with our bale house and for the price, well it certainly can't be beat!