We built our coop with kitchen cabinet doors from the Habitat for Humanity ReStore. This gives us the flexibility to open or close any doors for ventilation or wind. The base of the house is leftover metal braces from our garden shed. On top of that goes a leftover piece of cement board from a kitchen project. The cement board can slide out under the laying box if we need to clean it.
We bought a 8' x 3" post from the Habitat ReStore and made interior and exterior roosts.
We've blocked off the laying boxes temporarily until the girls are ready (they're 7 weeks now).
We also incorporated our compost bin into the coop design to give the girls the opportunity to snack on kitchen scraps and/or bugs (yum!!). There's an exterior door to the compost bin and another exterior door to get into the coop.
We thought we'd dog-proofed the coop pretty well by adding the pickets to the entire exterior ... our dog Lily seemed content to lie in front of the pickets watching the chickens for hours on end (chicken TV!). Well, that was fine until the day that it wasn't. For some reason Lily got it into her head to dig under the coop. We're not sure if she scooped out a chicken or if the chicken went out through the hole -- anyway, Paul was in his office when he heard a commotion outside and saw Lily with our chicken Spot. By the time he got outside, Spot was gone.
So now we're taking a few precautions: dogs cannot be outside unless we're out with them or the girls are locked inside the chicken house. I've planted bulbs and snow peas in front of the pickets, then laid down critter net. On top of that I laid down chicken wire extending three feet out from the pickets. I also put chicken wire around the side. There isn't a safeguard at the two doors (people door and