Well, I think I have heavy breeds anyway. I have 9 chicks - 2 Australorps, 2 Brahmas, 1 Favorelle, 2 Sussex, and 2 Welsummers. I'm just about ready to start building their coop & run (they're 2 wks old & still in their brooder - I know, I know, I'd better hurry!). I was thinking of putting the openings to the nest boxes about 2 feet off the ground (leaving about 16" under them, once you account for the supporting 2x4's). The openings are a bit higher than the bottoms of the boxes, so the nesting material won't get kicked out onto the floor. I was hoping to have the room under them for the chickens to use as floor space. So the nest box tops are about 3 feet off the ground. I was thinking of putting the roost at right about that height, since I thought 3 feet was getting up there for how big some of the girls are going to be. I don't really have room for a ladder since the coop is only 6'x6' and I need space for food and water and for me to walk around. The nest boxes are all inside the coop, so even though they don't take up floor space for the birdies, they do take up space for me to move around in. Is that too high for these breeds? Should I try to figure out some sort of ladder? Thanks for the help!!