We started the coop in the fall, it is 4' x 6' and it is fully insultated, and wired with electricity. Three nest boxes...blocked off one for storage, with a door to open up each one sepatately. The window is double paned and inspired by windows we saw in Sweden. Behind the roost is now a flat panel heater on a thermo cube for our cold winter days.
The coop still needs it's white corner boards and base, there is a sliding screen door made of hardware cloth... as there is japanese maple on the outside and a large rock on the inside that would be hit with a swinging door.