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Project Guide

How to Install a Dog Door

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Choose a Door
A dog next to a front door with no dog door

Before you install a pet door in your home, you’ll need to choose the right model. Consider the size of your home and your pet when making your selection. Here are a few tips:

  • Measure your pet. The dog or cat door you choose needs to be large enough to accommodate the height and width of your dog. If you choose a door too small, they may not feel comfortable going through it. You can easily find a small, medium or large dog door to accommodate your pet. Extra-large dog doors are also available to accommodate giant breeds.
  • Check the opening size. The opening of the door matters most – not the total size of the door with the mounting hardware. Your pet door should be at least 2 inches higher and wider than your dog’s measurements.
  • Find a space. Measure to make sure the dog door fits the exterior door and provides appropriate access to your outdoor space. Aim to leave a few inches on every side of the door for security.
  • Consider an alternate placement. Some models can be installed inside the wall, but the placement on these may be more difficult.
Mark the Placement
A man measuring the bottom of an exterior door
  • Trace the pet door template onto the area where you want to place the dog door using a pencil. 
  • Mark any essential screw holes as well.
  • Mark the inside corners of the dog door opening. This is where you’ll need to make your cuts. 
Drill Holes
A man drilling holes into the bottom of an exterior door
  • Use an electric drill with a 1/2-inch drill bit to make holes at the center point of each marking. 
  • Drill holes for the mounting hardware following manufacturer recommendations to ensure accuracy.
Cut and Prepare the Opening
A man cutting into the bottom of an exterior door
  • Cut the opening for the dog door with a hand saw. Start in one corner and cut along the outline you made with the template.
  • From outside the house, insert the side with no flap into the outer frame of the dog door. Make sure it sits flush against the door. 
  • Some models come with break-off levels that can be removed with pliers if the door is too deep. This will help make sure it fits correctly. 
  • Remove them one at a time until the pet door frame fits flush.
Place the Frame
A man placing the frame of a dog door into an exterior door
  • Insert the interior frame of the dog door – the one with the flap – from the interior side of your door. 
  • Insert the supplied screws, holding the door firmly in place to keep it straight.
Seal the Frame
A man sealing the frame of a dog door into an exterior door
  • Use caulk to seal the inner part of the outer frame. 
  • This will help keep outside air from entering your home.