INSULATED DOG HOUSES: ARE YOUR DOGS WARM ENOUGH?

Featured in the Sept/Oct 2007 Issue of Mushing Magazine:

If there is one thing I’ve observed the past few years of spectating and competing at sled races in the U.S. and in Europe, it is that the winning teams also seem to be the best cared-for teams.

Many factors contribute to a well cared for dog or dog team and warm, dry housing is one of them. Depending on where you live, train or race, keeping your dogs warm and dry in the winter can be as easy as keeping a dog house chock-full of fresh, dry straw or as involved as building a special, heated dog barn.

Of course, if your dogs live in the house, you probably don’t have a problem keeping them warm! When the ambient temperature drops during the colder months of the year, dogs living outdoors have to burn more calories to maintain their core body temperature. The opposite is true in the warmer months, where we see our dogs burning calories as they pant to keep cool, although this energy demand is not as great as keeping warm.

When a dog must produce heat to stay warm it consumes more food than other times, all other things remaining equal. If the dog must actually shiver to stay warm, its rest quality can be severely impaired. Any training expert, canine or human, will tell you that rest is a critical factor for recovery after conditioning.

The stress of physical exertion needs to be balanced by adequate rest for the body to recover and super-compensate from the workout. If our dogs are not resting adequately or properly, their conditioning, and almost more importantly, their attitude will suffer. Adding fat calories or just feeding more food during these cold months can offset the weight loss, but is the “quality of rest” addressed?

Obviously, the geographic areas we first think of as being harsh environments are the Northern interior areas of Alaska and Canada. Some Northern “lower 48” states can produce pretty cold temperatures also. The first I had ever heard of a dog barn being built was in Manley, Alaska by Susan Butcher. Susan’s dogs were typical Alaskan Huskies, with typical northern dog coats.

Susan knew how to maintain a team and keep them at their peak. The current trend of mixing shorter coated breeds with Alaskan Huskies has brought to light the issue of being able to maintain these dogs throughout the winter. Building a dog barn may be an option for some, but more and more dog owners are also turning to the more feasible option of a well-insulated dog house. Jeff Conn, a sprint musher living in Fairbanks, Alaska, conducted several studies to determine exactly how much a dog’s body heat warms up the inside of its doghouse during cold temperatures.

In December of 2001, Jeff installed a thermometer, with a remote readout, inside several different types of dog houses. To keep the heat-generating source as constant as possible, Jeff installed a standard incandescent light bulb to act as a heat source and also recorded readings with dogs inside the houses. To summarize what Jeff found out, and what he and the rest of us probably suspected, is that an insulated house with an open doorway stays warmer than a non-insulated house at any given temperature.

The difference between the inside and outside temperature was as much as 29º F during one reading. (Jeff used two different types of houses with insulation: one was an adapted standard house with the insulation applied to the inside of the house, making the interior space a bit smaller and more easily heated than the other type which had the insulation applied to the outside of the house.)

The readings also confirmed the fact that a smaller space is easier to heat than a larger one given a constant heat source. The biggest temperature differential, however, came from the smaller interior space house design that was insulated and had a plastic “doggie door” covering most of the doorway of the house. A whopping 41º F was recorded inside the house while it was 10F below zero outside. That’s a 51º F-degree differential! Four years later upon visiting Jeff’s dog yard, it was no surprise I saw mostly insulated dog houses there. Many mushers use a standard dog house that is approximately 2′ x 3′ made from one sheet of plywood with an additional 2″ x 2″ bracing in the corners.

Jeff’s insulated dog houses were adapted from just this kind of house. Cold Spot Feeds sells these pre-built, simple, sturdy houses at their store in Fairbanks, where one can see them stacked outside like doggie apartment complexes. Jeff devised a simple and relatively fast way to add 1.5” of blue foam insulation to all sides, top and bottom of the house. (See illustration above) Lighter-weight plywood is attached to the inside of the blue foam insulation to make a new interior wall around all sides and under the roof.

The insulation under the floor doesn’t need an additional layer of plywood and is left exposed. However, if the dog can get underneath the house to and reach the insulation it should be covered. Lexan TM is used for the swinging doggie door, which is easily attached when the temperature starts to drop with a standard 3” metal hinge, using a cordless drill. The doors are removed once it gets warm again. Lexan TM is used because unlike plain plexiglass or other plastics, it doesn’t get brittle in cold weather and is generally able to flex a bit more than plexiglass before it cracks.

Having invested more time and resources in modifying these dog houses, Jeff protects most of the edges where dogs can start chewing on them with metal corner beads. Jeff said most of his dogs learned to use the doors with no problems after a while. There were, however, a couple that refused to. At 50º F below zero, a dog that is so stubborn that it won’t go in its house is a problem.

Luckily few dogs lack this basic self-preservation skill, Jeff tells me. As we all may know, many sprint racers use a type of racing husky that has anywhere from ¼ to ½ bird dog bred into them. These resultant crosses are incredible athletes and generally can perform at their peak at much higher ambient temperatures than more heavily coated dogs. These dogs have been used in Scandinavia for mushing and skijoring sports for quite some time and the mushers there learned that these types of dogs do better in insulated houses or dog barns.

Egil Ellis now lives in Willow, AK where it doesn’t get as cold as the interior of Alaska, but generally sees temperatures similar to the colder parts of New England or Minnesota, albeit for more months of the year. Egil made his houses modularly in Sweden before he moved to Alaska, and assembled the parts of each house here. They took up much less space on the cargo flight this way. He also used 1.5” blue foam insulation but doesn’t screw the top of the dog house down to have easy access to the interior of the dog house for cleaning out straw. (See photo on opposite page) the resultant dog house is very similar to the ones that Jeff has adapted, with one exception: no doors.

Egil feels that this type of house insulates so well that there is no need for doors, at least not where he lives. His houses retain heat so well that, “You can put your hands inside the dog house to warm them up!” Egil tells me. “The straw inside an insulated house always stays drier because there is little or no condensation on the interior walls,” Egil adds.

The dimensions of Egil’s houses are: 32” wide, 24” deep, and 24” high. The offset opening is approximately 10”x12” and is framed with 2”x6” lumber for better wind protection. There is another type of house that can be used without insulation to add a bit more protection than a standard house. It is commonly referred to as an arctic entry house and utilizes a divider inside the house to make an even smaller, more wind-protected space inside. The divider has an opening similar in size to the outside opening that the dog uses to go from the “lobby” of the dog house to the “sleeping quarters.” Adding insulation and/or a swing door to this house would make it just about the warmest of all the designs.

 

Greg Sellentin is the Publisher of Mushing Magazine and the former publisher of Sled Dog Sports Magazine where this article originally was printed in 2005.

Taking 30 sprint dogs from New Jersey to Alaska has opened his eyes to what real cold is.