Such care in building to safeguard your babies. Outstanding job.My Coop
We had the advantage of an existing structure in the form of an old goat pen. The first thing we did was line the floor with 1" hardware cloth and tack it to the sides. This may sound excessive, but it seemed more logical than digging a 12" trench around the whole pen to bury the mesh. We added 6" of topsoil over the mesh. It has thwarted several tunneling attempts.
There was old chicken wire wrapping 3 sides of the pen that I had to take down. We replaced it with 1/4" hardware cloth.
This is the henhouse. We designed a 4'x8' plywood box with vents, windows, laying boxes, and access doors. It is on it's side waiting for the bottom sheet to be attached. It is resting on a simple raised redwood foundation.
Close up of a vent and window
Laying boxes- also plywood.
The cube has a floor and ceiling now.
Attaching the laying bins
Installed the roosts
Added the front wall with access doors
Framed in the front of the pen and added more hardware cloth
Built a barn style door
Brought in the chicks! They were ready.
The ladder is a drawbridge we can raise from outside. This gives the chickens 2 layers of protection from predators. It was nice when we had a rooster and could keep his early crowing muffled. We stopped raising it when we increased the flock and most of the new birds chose to sleep on top of the henhouse.
from the San Diego High desert. 
