Chickens!

-Roost(s): I’ve had birds that preferred sleeping in nesting boxes (Silkies) and Leghorns that prefer roosting at night. Having a large roost or one that staggers is a nice sleeping area.

Silkies will do this because they cannot fly worth a damn. Be careful, I've had silkies go broody without any eggs simply because there was a nest box. They are baby crazy hens. You should never let your birds sleep in the nest boxes as they will foul the bedding quickly. I've had to add a curtain to mine to keep young pullets from avoiding the roosts and roosting in the nest boxes.

-Heat lamp: It depends on the bird but if it gets below 40F a small heat lamp can do wonders for nighttime

#1 way to burn down your coop and kill your birds. Chickens regulate their body temperature with feed, so just make sure they have plenty of feed and your birds will do just fine without a heat lamp. They just need to be out of the wind. While we don't get a lot of sub-freezing temps here in Central Texas, my girls made it through several cold snaps last winter that drove temps to or just below freezing overnight without heat lamps no problem.