Good advice thanks! We do get routing cold snaps of-40 and -50 that last for weeks. My garage is +50 during the winter. Would the birds get sick if I kick them out to peck sunflower seeds out of the snow?
Huh... going from +50 to -50 is maybe too much of a swing???
I have never had that big of a temperature difference at my place...
My chickens have a big coop connected to an outside run as well as a greenhouse.
The colder it gets the less they choose to go out. By the time we get to -20F I don't think they ever enter the run, unless there is ZERO wind. And even then, they do not go into the run for long.
So.... I guess I am saying that at -30F and colder, they will want to have zero wind, which means no, they will NOT want to go outside and scratch about in the snow.
If you can make a run and wall it with clear or clear-ish plastic, that will give them a wind free area that they are much more likely to want to use. It is best if you wall up all sides, and roof, but then have a single side that is mostly open. This way, even with a huge open end, since it is the only opening, there is zero draft, but still good ventilation.
As to giving them snow to drink, MANY people do that! It can be fully successful. However, drinking snow is more taxing on their bodies since their body then has to warm up the snow. So, giving them only snow to drink will increase how much feed they need to eat.
Talking of feed, I do think, especially at your latitude, that you should put a light on a timer for them, so they have 10 hours of light. They will not eat in the dark. The colder it gets the more they will eat.
But really.... at your temps, and with only 3 hens.... I think I would figure out a way to keep them in the garage 24/7 as soon as it starts to stay below -20F for long periods. You could even set up a cool series of cages in the garage, each cage connected to the next by a tunnel. Like a hamster cage. Might help utilize the garage space more effectively, and give them the space they need to stay healthy.
As to ventilation.... if you are having issues figuring that out... I would suggest opening up the garage door for an hour every morning... that will help, might kill you on the electric bill though. .. unless you heat with wood or coal???