the bottom level on the floor, underneath the nestboxes is where we've hatched our last 3 broods.
starting when a hen goes broody and is DEFINITELY sitting on her chosen eggs, we enclose her using vinyl "hardware cloth" stapled to the floor and ceiling, with a doorway to put food and water in there under their stairs. The broody hen needs to be protected from UBERbroody hens who will take over the job just before hatch, by attacking the poor broody hen and pulling her off the nest and stealing her chicks. Enclosing her also prevents sneaky hens from laying more eggs under her, which prolongs the hatch over several days.
Then, the broody hen and her chicks need protection from the pecking order of the flock for a few days. When they DEMAND to be let out, we do so, supervised, for a few days. Once the chicks are big enough to get away from a pecking chicken, they manage very well with the protection of their broody.
Prolonged hatches aren't the end of the world, though. Our Esther hen was the last of 11 chicks hatched over 8 days last September, and she had to run hard to keep up. Today, she's the smartest and strongest of the flock.
Good luck to you and yours
!