What age do a put a roost in the pen?
I have 2 X 4's wide edge up set up as a ladder (2 slanted ends w/ the roosts stretching between them. I cut 45 deg ends on the end posts, then leaned them up on the house so I could draw a line for where the top edge of the roost bar should be so it would be level. Mine fits into the coop w/ bottom and top edges of the side bars resting on the floor or wall, so its not attached to the coop but won't fall or shift. I used screws to attach the roost bars so I could take it apart to move it if needed. My coop is a 5X8 rectangular box w/ half closed and the other half 1" wire mesh. I have an eyelet bolt at the bottom of one end so I can tie a rope to it and move it w/ my truck. Just a flat roof of metal.