Building some roosts inside the new coop and I'm wondering how high I can make them? Coop is 10' x 8' and we have 4 layers and 16 2.5 month old chicks that'll be going in there. I'd like to put them fairly high, so that we can move around more easily to clean; but I don't want to make it too hard on our girls. What height(s) is recommended??