An appropriate size for a homemade doghouse is wide enough for your pooch to turn around in and long enough for him to lie fully stretched out. A doghouse should be a few inches taller than your pooch when he's standing inside. The entrance size is determined by measuring your dog, and the placement on the front varies due to your climate. Cutting the entryway out of a wooden doghouse correctly allows warmth in the winter and cool breezes in the summer.
Measure your dog’s height. Have your pet stand on all four legs. Stretch the measuring tape from the floor to the top of his shoulders. Round the measurement up to the nearest inch and multiply it by .75. This is the entrance height needed for your dog. Dogs duck their heads when entering a house and step over the threshold at the door's bottom.
Measure your dog’s width at his widest point. This is generally the chest area, unless your dog is plump. Add 3 inches to the measurement to allow him to enter the doorway easily.
Mark the height and width measurements on the front of the wooden doghouse using a carpenter’s pencil and a metal measuring tape. Leave a threshold of about 3 to 4 inches near the bottom of the doghouse when measuring to keep rain or water from blowing into the doghouse. Center the entrance in warm climates. In colder climates, shift the entrance toward one side so your dog can move to the other side and find shelter from cold winds blowing through his front door.
Cut along the marking lines with a reciprocating saw and remove the piece of wood to form the entrance.
Cut strips of old carpet or a rubber bath mat with a utility knife in 1-inch wide pieces and the same length as the height of the doorway. Cut enough strips to fill the doorway's width.
Align a carpet or rubber strip on the left, upper corner of the entrance. Attach it to the wood above the entrance with a staple gun. Place a second strip next to the first and attach it in the same manner. Continue stapling the strips to the right of the previous one until the doorway is filled with strips.
Place a concrete block or bricks under each corner of the completed doghouse to elevate the structure and prevent water from ruining the wood and wetting his bedding. Make sure the house isn't too tall for your dog to get inside, however; if so, he may need a ramp.