Is a 2 x 4 roost with flat side up like I would do for chickens best? One has taken to roosting on a small secondary coop in the enclosed run over night, but he still looks like he'd prefer to be higher. The other one still goes into the coop at night, and usually chooses a wider shelf to roost on in there. What would be the best type of roost to provide...for both inside and out? Thanks!