Roosts are best as low as possible.
Here's my theory on the 'stack up' aspect to coop design:
Bottom of pop door is best about 8" above floor so bedding doesn't get dragged out of coop.
Nice to have bottom of nests about 18" above bedding to allow use of that floor space under them(doesn't count if your nests are mounted on outside of coop).
Roosts are best about 12" higher than nests so birds won't roost(sleep) in nests and poop in them, if you use poop boards under roosts it will also 'stretch' your floor space.
Upper venting works best as high as possible above roosts so no strong drafts hit roosts in winter...and hot/moist air and ammonia can rise and exit coop.
Here's my theory on the 'stack up' aspect to coop design:
Bottom of pop door is best about 8" above floor so bedding doesn't get dragged out of coop.
Nice to have bottom of nests about 18" above bedding to allow use of that floor space under them(doesn't count if your nests are mounted on outside of coop).
Roosts are best about 12" higher than nests so birds won't roost(sleep) in nests and poop in them, if you use poop boards under roosts it will also 'stretch' your floor space.
Upper venting works best as high as possible above roosts so no strong drafts hit roosts in winter...and hot/moist air and ammonia can rise and exit coop.
