Yep, the little roosting bars that come with prefab coops are for chicks. Once they are fully grown they need something bigger to hang on to. My gardener (who does odd jobs for me, like building the low roost) accidentally cut up the only roost I had for inside, but fortunately we found one of the pieces. My husband attached pieces of the little rod to the 2x2 new one (so it would fit on the original brackets made for the little one.), and now I can see they are much more comfortable with the bigger rod. I use 2x2 redwood or a birch limb that is at least 1 3/4" diameter. They like both.