The animal is then able to generate the necessary body heat, Fortney said. Smaller animals may have a more difficult time storing a lot of fat and, therefore, may be more vulnerable to the cold than larger breed dogs. Dog owners can help their animal stay warm by providing a dog house that faces south with a flap to block the wind, Fortney said. The house should be insulated, with care taken to make sure the dog cannot get to it as insulation contains fiberglass that can be very irritating to the animal. A small light bulb can provide a small amount of heat in the dog house.
Proper bedding can also provide additional warmth.
Changing the straw has to do with it getting wet, not so much with it getting dirty. In really snowy times it might be a good idea to change straw every two weeks. Otherwise, once a month is adequate. Old bed spreads are another option. I like them because you can take them to the laundromat and get them cleaned and then put them right back in.