If I was "getting a house built" in a cold climate, I would really worry about windows.
Make sure they are the best you can get and limit the amount on the north side,
or those that can't see much sun during the day.
The north side of my home has an add-on Den. The sliding Anderson windows keep that room extra cold all winter!
I am now considering adding another layer of glass over them.
Storm Windows ? Rolling Storm Window by Harvey
The sliding Anderson windows come packed with buyers remorse.
They leak and double pane just isn't enough for shaded areas when it 10 deg outside..