Poultry adapts pretty well in freezing temperature. Are any of your ducks or chickens equatorial or heat-loving birds? If that is the case, I don’t know what to tell you to be honest.

Otherwise, the main issue in very cold temperatures is keeping their water supply from freezing and/or keeping them from spilling the water and getting themselves wet or the ground around the water wet.

The shelter should be dry and draft-free, but not air tight or you will get humidity which isn’t good in subzero temperatures.

@bkcunningham thank you, mate.

Wow, so a live chicken can get freezer burn?
Do you keep them in cages, or in a barn?
I would think you would want to keep them a bit warmer. Raising chickens can help guarantee healthier food, but I can’t imagine this being good for them.

It sounds like a good idea to make sure your coop faces the south or southwest, because they’ll get more sun in the winter. You can concoct shade for them in the summer.

I have kept chickens but at this time I have geese and they are pretty hardy, but do need shelter in severe weather. I lock my guys in a barn every night with deep pine shavings for bedding. Chickens can get frostbite on their combs and wattles so a heat lamp ( but not light, which will mess with their laying cycles ) might be in order in extremely cold weather.

Always feed plenty of scratch grains before roosting as it generates extra heat during long, cold, winter nights.
Good ventilation is important in barns and coops even in the coldest of weather.
Ducks and geese abandoned on crappy ponds in winter, can and do, die from starvation and often, in some areas, like the east coast can become frozen into lakes and ponds.

There is a great website for a favorite rescue group of mine that can give you lots of great info. if you sign up for their monthly newsletter.

www.majesticwaterfowl.com

A heat lamp or a space heater will keep them warm enough. If you use a space heater keep it separated from the chickens, our neighbor in ND used a screened off area of the coop to keep the heater from the chickens and their mess.

The coop itself was made of uninsulated plywood.

Stop excess drafts but keep the ceiling vents open and the air moving (dry > that last little bit of lost heat especially since that’s where a lot of humidity is), add some extra bedding, some insulation (something easy to remove after winter), and keep things clean (better for dryness). Cold-hardy chickens can handle 0 just fine and -20 isn’t usually a problem if they’re otherwise healthy. Make sure they have a extra feed and keep the water liquid. If you have a stretch where there’s no sun and the days aren’t heating up use a ceramic space heater (very very carefully, especially in a small coop). Most important, keep an eye on them, nothing will be better than you checking up on them so you can adjust things as needed.