I want to build a ladder style roost. What angle should I put the ladder to avoid the chicks on the lower rungs being bombed all night by the upper ones? How far apart should the rungs be? My coop goes from a 10 foot ceiling down to just over 6 foot. How high can I safely go? I will be getting 8 Buff Orpingtons, 7 California whites, 5 RIRS.