Even though your dog house might be insulated you should consult with the experts about whether or not you need a heated dog house. When living in extreme cold remember that your pet though hardy still suffers from the elements. Not only can your dog become ill but can suffer serious injury if he or she is exposed to too cold a climate.
If you live in a location where there are extreme climate changes. Like in NYC where the summers are almost unbearable and the winters bring snow and sleet. It is a better idea to get heater-air conditioner-dehumidifier. All of these together make for a much more comfortable dog, and I mean that you have to worry less about the affects of the climate on your pet.
I have a heated dog house
but I installed the heater after learning the hard way what the cold can do for your dog. To be honest I had never lived myself in a cold climate so I really was unprepared for the snow, ice and freezing temperatures when they came. I thought that my dog who is long haired would do just fine in the cold. Little did I realize how my ignorance would cause him to suffer that first winter. Thankfully he didn't suffer any permanent damage and now he is cozy and warm in his insulated heated dog house
Heaters really don't have to cost very much and as long as you are faithful to have them checked and serviced regularly they are really very safe too. Take a tip from me and beware of that cold.