Our two dogs are outdoorists. Except during single-digit temperature nights, they sleep in igloo-style houses, one for each dog. The doghouses are only used in the winter and I place them close to the house in an inside corner where they're protected from the wind by our house on two sides: north and east and by the outside walls of the doghouses on the west and south. The protection is needed because the doghouses are poorly designed with a large and direct egress. This was particularly evident during one of last year's snow storms when the houses filled with drifted snow despite the wind protection. We brought the dogs into the sunroom during the snowstorm and they spent nights there until we could clean out the doghouses and dry out the bedding. The sunroom is where they spend single-digit nights. It's unheated (except by the sun) and never colder than 40 degrees, dog-level.
This year, in an attempt to avoid last year's snow problems and to make the houses warmer in cold weather, I built a vestibule to connect the two doghouses. Once I get a curtain across the opening to the outside, they should be 'snug as a bug in a rug.'