I have 2 quotes for building a 12 x 20 saltbox style coop. One elevated 24 inches on 4x4 vertical posts with 2 x 10 treated joists spaced 16 inches OS and 3/4 inch plywood floor glued and screwed. The altenate is with a concrete floor 4 in thick with thicker edges. Either option is the same price.
With option 1 I'd likely insulate the floor with foam sheets, lay down linoleum, and their would be the cost of hardware cloth around the foundation (and beneath the floor joists)so it actually would cost me more. I would lay down a few inches of sand before construction begins.
I have a small 6x6 coop that is elevated and I really like the space for the chickens to get out of the weather yet be outside. I just can't decide which option to use on the larger building. Is there something I'm overlooking about such a large building being elevated? I'll have lots of double hung vinyl windows (I got cheap on Craigs list.) Would the raised coop sway enough to cause problems with cracking?