Right now, we have made a roost out of a garden trellis--the rods are not circular but square and about 1 in in 'diameter'---is this ok? Or do we need to construct something out of 2x4s? Our chicks are 5 wks old so we have a little time but they are starting to enjoy the roost a bit... If we need to construct something new, what should it be? Any pics, please? Help!!!