We bought the shed 7x7 for storage use only, therefore, my husband got a plastic shed. After we got ducks, I've made them a small coop, then the chickens started to pile up, so we moved them to the shed and I've made them nest boxes and 2 roosting bars. Then, we got some more chickens, so I've build a nother coop with 2 floors. Some do stay there and others in the shed at night. The way my husband and brother put it together, the doubel doors won't close. I sealed the first door and let the other door little open so they could come in and out. That's the only entry they have to the shed. I've put 2 big heating lights and a lot of hay inside, but it's still feels cold. And the run being the way it is (you'll know what I'm talking about if you read my BYC) we have decided to change the location of their run and shed/coop to a much drier and sunny location.
The door to the shed will be outside and a little door from the shed that will lead them to the run. In the front of the current shed, we were thinking of completely re-done. One door instead of two and a little window. We are also considering to buy a new shed or a coop for them. Let's see what happens. I just want them to be warm and comfortable for the winter.