What Is a Double Coat, and What Dog Breeds Are Double-Coated?

These two layers serve vital functional purposes beyond just looking good. In colder months, the undercoat traps body heat to keep your dog warm. Conversely, during spring and summer, that same dense undercoat acts as an insulator against external heat, trapping cool air near the skin to prevent overheating.

The ratio of topcoat to undercoat can vary significantly between breeds. A denser undercoat often gives dogs a fluffy, cottony appearance, but it also means more shedding. During seasonal changes, particularly spring and fall, double-coated breeds shed heavily to adjust their insulation levels, requiring consistent brushing to manage loose fur and prevent mats.

Certified master groomer Jennifer Bishop-Jenkins identifies four main variations of double coats: short, medium, long, and triple (or Arctic). The specific type depends largely on the breed’s historical function.

Medium double coats are common in herding breeds like Border Collies and Australian Shepherds. These dogs require weekly brushing to remove loose fur and prevent tangles. Trimming excess hair around the feet, hocks, and pasterns can also help maintain hygiene and comfort.

Triple coats, found in Arctic breeds like the Samoyed, Alaskan Malamute, and American Eskimo Dog, are exceptionally thick. They feature a dense, oily undercoat designed for survival in extreme cold. Grooming these coats requires patience; simply combing dry hair can cause breakage. Instead, use a high-velocity dryer after bathing and line-combing to fully separate and dry the layers.

A common misconception is that shaving a double-coated dog will help them stay cool in the summer. In reality, shaving removes both the protective topcoat and the insulating undercoat. Because these layers grow at different rates, shaving can lead to "coat funk" or alopecia, where the undercoat grows back faster and denser than the topcoat, leaving the dog with a patchy, uneven coat.

"Shaving doesn't do anything to cool dogs off because a dog's cooling system is different than ours," explains Teri Becker DiMarino, President of the California Professional Pet Groomers Association. Dogs regulate temperature primarily through panting and sweat glands in their paw pads, not by exposing their skin to air.

Furthermore, removing the topcoat leaves the skin vulnerable to sunburn and insect bites, while eliminating the undercoat removes the natural barrier against heat and cold. There are only two acceptable reasons to shave a double-coated dog: prior to surgery or as a last resort for severely matted coats that cannot be brushed out.

If a double coat becomes neglected and tangled, a careful, step-by-step approach is essential. Bishop-Jenkins recommends wetting the dog and applying a thick, creamy conditioner to the matted areas. Allow the solution to soak for about an hour to loosen the knots gently.

After soaking, use a line-combing technique. This involves parting the hair into small sections and combing upwards from the skin, working forward line by line. This method lifts and removes loose hair without pulling painfully on the skin.

Always use grooming tools that fit your hand comfortably to ensure precision and safety. Regular maintenance prevents severe matting, making grooming sessions quicker and less stressful for both you and your pet.

Since you shouldn’t shave your double-coated dog to keep them cool, focus on other cooling strategies. Provide access to shade and plenty of fresh water during hot days.

Consider using cooling accessories such as dog cooling vests, bandanas, or mats. These items help lower body temperature safely without interfering with the dog’s natural insulation system.

Regular brushing is key to heat management. Removing dead undercoat allows for better air circulation against the skin, helping your dog stay cooler naturally.