You could make something like a large cage around the nests/roosts--wood frame, hardware cloth on top and sides, wood or similar for the floor. That could take care of predator-protection, and the roof is already there to shed rain. Allow 4 square feet per chicken inside the space, and close them in each night (if they're used to sleeping there, they'll put themselves to bed shortly before it gets dark.)
You're right that chickens do need a safe space to sleep, but you don't need to make it dark for them. The sun going down makes it dark enough.
You're right that chickens do need a safe space to sleep, but you don't need to make it dark for them. The sun going down makes it dark enough.
