Novel?...Bible more like it?..Kidding. ,I'm in PEI, Canada, so we don't get winter as bad as you, but it's still pretty cold! This will be my first winter with our chickens.
We have 5 hybrid Buff Orpington/Barred Rock hybrids that I bought from a local farmer as chicks. I was looking for cold hardy, friendly breeds that laid a lot of eggs as well. Where I raised them from week old chicks, they are very friendly and tame (they get tamer and less flighty as they mature). Buff Orpingtons are a bit later to start laying than some other breeds, but they have smaller combs and are a heavier breed, which is what I was looking for.
Henrietta is the first of my girls to start laying at 25 weeks. The rest of the girls look like they're almost ready to start laying. We've gotten an egg from her 6 days a week for the last 2 weeks.
I think your primary struggle might be maintaining liquid water. It only takes our waterer an hour to freeze over when it's -15C, and if you aren't going to provide a heated waterer, you're going to be hauling fresh water to your birds every 30 mins, although they will only drink when it's 'daylight'. I have a cookie tin with a 60W lightbulb that sits under my chickens waterer to keep it from freezing in their run which works well.
If you're concerned about getting year round eggs... With your lack of daylight hours in the winter up where you are, and the fact that you're off grid, you may consider solar powered lights to turn on a few hours before natural sunrise to keep egg production. This might also work for 'heating' their water. Just make sure to collect the eggs right away so they don't freeze. I don't provide supplemental lighting - we get a minimum of 8.5 daylight hours in the winter.
As far as heating goes, the coldest it ever gets here (without windchill) is -25 C. From my research/experience, it's more important to acclimatise your chickens to the cold than to heat the coop. I like your idea of putting sod over the roof, and putting it into the ground, but like another poster said, you'll need to line it with something to keep out critters. We use straw bales around the outside of the coop to provide some thermal mass/insulation, and I use the deep litter method for their bedding, but that's it for 'heat'. A major concern would be to ensure they have enough space, and LOTS of ventilation far above their roosts to allow the moisture to escape (while providing a draft-free environment).
I didn't bother with a rooster for a few reasons: 1. I don't eat meat, so my hens are just for eggs and pets. If you're looking to supplement your food supply with chicken, having a rooster for breeding might be for you. 2. Roosters have larger combs, which are more susceptible to frostbite, which I didn't want to experiment with my first year. 3. My hens have an enclosed run, which has been predator proof (so far), so I don't feel I need a rooster for protection.
Sorry for the novel - I hope my answers are helpful! Good luck with your chicken journey
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