How to Choose the Right Size Dog House Measure the length of your dog from the tip of the nose to base of the tail. Using this measurement as a guide, the dog house should have an inside width and depth 25% greater than the length or your dog. Measure the height of your dog from the ground to the top of the head. The height of the dog house should allow the dog to stand without hitting their head on the roof. Depending on the pitch of the roof , this generally means the height of the dog house should be up to 1 ½ times the height of the dog. If purchasing a house for a puppy, use the size of the parents or expected size of the puppy when full grown. When in doubt, choose a larger size house.