Have had chickens on and off for 50 years and never lost one to the cold, never have used any type of heat. I heat the water only. as others have said, the right breed and draft free is all that is required.
They are great birds, very docile and good layers. You might also check out
Black Australorps. both breeds are cold hardy if that is a concern as well.
Live in north Central Pennsylvania, last year we had -28 below, I have no heat in the coop. As long as you keep them out of drafts they will be fine, thats why they have feathers.
I made mine out of plywood, I have two 2 x 4 sections, makes it easier to manage. Put a small layer of pine shavings on the board for the droppings to drop into, this way the poop wont stick to the board and it makes it real easy to clean. I use one of those concrete plastic mixing tubs to dump...
I have five nest boxes for 20 hens, they typically use only three of them, in fact one of them usually has ten eggs in it while the other two get a few each.
Just about what everybody has said, roosts above the nest boxes and a poop board underneath for easy cleaning. I used to have roosts with a ladder arrangement but the birds fought over the top tiers on a nightly basis. Now I have the roosts at the same height and two parallel to each other, no...
I have buffs in with australorps, bhramas, Rhode Island reds and leghorns, no problems at all. I usuall7y isolate the small birds from the flock until they are 16 weeks old and are big enough to take care of themselves.
If I read this right, it uses dowels for the roosts, not the best idea IMO, especially for the Northern climates. A 2x4 with the wide side to perch on works better.
My Buffs are outside in the snow as I write this. Its 12 degrees now and was 2 last night, I have no heat in the coop and they do fine. Last year it was -28 overnight and no ill effects.
Have raised chickens on and off for 50 years and have never worried about the cold, it was -28 here last winter and no problem. I do not heat or insulate, but my coop is well ventilated and draft free.
I put a angled reflective panel over the roost area in the winter and it works great. We have temps here in northern PA way past the zero mark, -28 last year. My coop is insulated with no hear source.
I use two parallel roosts, 12 inches apart, about two and a half to three feet off the floor. i like the parallel roost as the chickens dont have a nightly fight to see who gets the top rung.
I have the drop boards under the roosts, about eight inches as I recall, and use a layer of pine...