I'm building a chicken tractor with a 4'x8' run on the ground. The feed, water, nest boxes, and roosting space will also take up that whole 4'x8' footprint on a "second" floor above the run. I'm playing with different heights between the ground and the floor of the upper level. Eighteen Inches? Two feet? Two-and-a-half feet? I thought I'd throw the idea into the public forum to see what people thought. Our chickens will spend most of their time within the confines of the tractor (i.e., minimal free range), and I didn't want to make things overly claustrophobic for them. We have a Leghorn, Red Star, & an Araucana--all hens.