poopboard location

[pittsbirder]

my first coop is about done and ready to install inside stuff. i have a 6 ft wide by 3 ft deep coop 3 high in front. i was gonna put poop board in front by the barn doors with water and food right under it for feeding with roost above that. nest box to far left and pop door to far right on the floor. is having the poop board right where i open the doors a bad idea and how much of a lip does the poop board need if im using sand as a catcher? how far from roof can the roost bar be? i got amber link birds, a cross of long isl. reds and a plymoth white. Thanks