We're finally looking to get some chicks, a rooster, and possibly a guard gosling this spring. We're plant hardiness zone 4a (Canada) I believe, and get about one to three weeks of -20C in a normal winter, maybe a burst of -30C for a day or four but getting noticeably more mild these days with climate change.
So the question: Are there any breeds of egg or heritage birds that can handle that amount of cold in an insulated coop without heat or should I plan on a little ammo can waste vegetable oil heater for the few cold days/weeks? (We're offgrid and don't even have proper power for ourselves yet, so a heatlamp or anything like that wouldn't work for us). I don't mind if they don't lay through the winter but I want them to be comfortable in the coop at minimum.
I'm going to be building a roughly 1.2m wide x 1m tall x 2.4m long coop (4ft x 3ft x 8ft) very soon. Thinking low wall height to keep it warmer, but maybe I should go with 1.2m (4ft) high walls to allow for more air circulation and roost bar spacing? Thinking 4" rockwool walls and probably 4" for the roof and an exterior insulation panel on top. Want to keep the construction fairly light so 6" walls may be out, unless I slap exterior insulation panels all around. But they aren't cheap. Some amount of rockwool panel under the floor. Probably go with the deep litter method for free added bottom insulation too.
It'll most likely be an elevated chicken tractor setup with a (highly) electrified caged grazing area coming off the coop because we have a lot of black bears on our property in the summer, as well as some other predators. That way they'll have fresh scratching ground every day or two, whenever they've torn it up. People nearby just free range their hens and roosters without much issue, but I don't think we can get away with that here since they said they rarely see bears on their property.
Also wondering could they all be housed in the same coop if they're raised together from hatching or is it more common to separate the rooster and maybe get him a social buddy instead? I kind of assume for the rooster and/or goose to be effective guardians they need to be IN the coop but idrk.
Thanks for any insights!