Most days we don’t use the trap door at all–we just let them out in the yard during the day, and close them up in the coop at night.
But the trap door to “Guantanamo” works great when we need it, and we’ve been grateful for this setup many times.
Some chicken keepers leave the water and food out during the day.
We leave both of them open during the day, and although the chickens can jump in and out of the human door, they usually prefer to use the chicken door. We completely enclosed the area beneath the coop with 1/2 inch metal hardware cloth, buried 10 inches into the ground.
We also buried a “floor” of hardware cloth several inches under ground, and sewed it with wire to the buried fence to prevent burrowing by rats/raccoons.
At the end of this post there’s a downloadable plan with all the dimensions of our coop.
Our coop design has two doors: a big “human door” in the front for easy access, egg gathering, ventilation, and cleaning, and a chicken door on the left side with a ramp. Though the chickens have a larger run, underneath the coop we built a cage Tom calls “Chicken Guantanamo,” where they can be outdoors and still be fully protected if we need to leave them for an extended period.
As you can see, the coop is raised on cedar posts set in concrete footing, and framed they way you would build any small shed.