I have various thicknesses of fallen tree limbs and 2x4 boards used as roosts. I have large, small, and bantie chickens(silkies,too) and every single one of 35 roosts. The banties roost on a gate about 30 inches high, but the others like it as high as they can get. I had to lower mine a bit since I have some large heavy girls and didn't want to injure their legs or feet, plus they are always knocking each other off for 20 minutes every night rearranging the positions. Mine had teensy roosts in their brooder at the beginning as 2 day olds.