How to Make a Pet Door for a Garage

Giving your pets access to your garage without opening your garage up to intruders or to the full force of weather is easily accomplished through a properly installed pet door. While the most weatherproof pet doors can be purchased through pet supply stores and come with ready-made instructions, it's possible to build your own version that will be nearly as effective, and far less expensive than a prefabbed pet door.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Measuring Tape
• Wood
• Saw
• Nails or Screws
• Hinges
• Hammer or Screwdriver
• Caulk

1. Plan the size of your pet door. Measure the area you need to leave open for your pet to crawl through. Drill a hole in the center of the space where you wish to place the pet door from the interior to the exterior of the space. If you don't have a long enough drill bit, take measurements so that you can drill in the same spot from each direction. Use a straight coat hanger pushed through the hole and a tape measure to take a measurement of the distance between the inside of the wall of your garage and the outside wall. This is how wide your pass-through boards (which will sit like a window frame) will need to be.

2. Construct your door. Cut the lengths and widths of board necessary to make your sill frame, and screw or nail them together into a frame. You should have what appears to be a rectangular box with no top or bottom. Cut four lengths of wood that can be screwed down to the sill frame pieces. Ensure that the outer edge does not stick into the box, but rather acts like a shelf protruding from the box (sort of like flaps open on a box). Screw the pieces down like a picture frame, and cut lengths for the reverse, but do not attach them.
   
   Attach hinges to the top of the door frame in the center so that when the door is attached it will swing in both directions. Measure and cut your door carefully so that it fits easily in the hole, but does not leave any more gap then necessary to swing freely. The closer you get this measurement, the more airtight your door will be. Connect the door to your hinges. This will give you a framed door that swings both ways when set vertically, with a lip on one side and and not on the other. However, you will have the lip pieces ready for the other side when it is time to connect them.

3. Cut your hole. Measure the exterior of the box, not including the lip, and cut a hole in your wall clear to the outside that is EXACTLY those measurements. When you are done, you should be able to push the door box through the hole until it hits the lip. The lip acts as the guard to keep the door box from going all the way through the wall.

4. Install the new pet door. Once you have placed the unit through the wall, your open box end should be flush with the outside of your wall, and the lip on the other side should be flush against the inside wall. Connect the unattached lip pieces to the outside, and screw the lip pieces into the wall from both sides so that they are connected not only to the box, but also to the wall from both sides of the entry. Your finished pet door should swing freely.

5. Apply a bead of waterproof caulking around the outside edge of your new door where the lip meets the garage wall. This will keep water out of the unit, preventing erosion due to rot.

References

• Standard Prefabbed Pet door Install