Pet Door Installation: Cut Clean, Sealed, and Sized Right
Giving a dog or cat its own door sounds easy until you're staring at a good door or an exterior wall, about to cut a hole you can't un-cut. Get the size or height wrong and your pet won't use it; cut into a wall without knowing what's behind it and you risk wiring, studs, or plumbing. A sloppy opening also leaks air and water, turning a convenience into a draft and a maintenance problem.
A pet door is a permanent opening, so the work is equal parts careful measuring and clean cutting. The flap has to match the pet, wide enough for the body and set at a height that clears the back but isn't a step up the animal won't take, which is why the shoulder height and width are measured before anything is cut. Cutting through a door is mostly about a square, correctly sized hole and a frame that clamps the two halves of the unit together. Cutting through an exterior wall is a bigger job: AZ Smart Fix has to check for studs, wiring, and pipes, then frame the opening and build a weather-tight tunnel through the wall thickness. Either way, the finished door should seal against drafts and rain when the flap is closed.
How the job is done
- 1
Size the opening to the pet
We measure your pet's width at the shoulders and the height from the floor to the top of the back, then size the flap and set how high it sits. The flap should be tall enough to clear the pet and low enough that stepping through feels natural.
- 2
Choose the location and check what's behind it
We decide between a door panel and an exterior wall, then probe a wall location for studs, electrical, and plumbing before cutting. Knowing what's inside the wall is what keeps a clean job from becoming a repair.
- 3
Mark and cut the opening
Using the unit's template, we mark a square opening and cut it with the right blade for the material, whether it's a hollow or solid door or a sided wall. Steady, accurate cuts mean the frame seats without gaps.
- 4
Frame a wall opening
For a through-wall install we frame the opening so it's solid, then build a lined tunnel that bridges the interior and exterior walls. This box is what makes the unit stable and keeps the wall sound.
- 5
Mount and secure the unit
The interior and exterior frames are joined through the opening and fastened so the assembly is rigid and the flap hangs straight. We confirm the flap swings freely and falls fully closed on its own.
- 6
Seal and weatherproof
We seal the perimeter against air and water with the right exterior-rated sealant, and check that any built-in weatherstripping seats. A flap that closes tight keeps drafts, rain, and pests out.
What a pro checks
- Sizing is based on the pet's shoulder width and back height, not its weight, so the flap clears the body comfortably.
- A flap set too high becomes a step the pet avoids; the bottom of the opening should sit at a height the animal steps through naturally.
- Cutting into an exterior wall means checking for studs, wiring, and plumbing first, which is the difference between a clean install and an expensive surprise.
- Through-wall installs need a framed, lined tunnel so the wall stays structurally sound and the unit doesn't flex.
- An exterior-rated seal around the frame keeps humidity, rain, and drafts from getting in around the opening.
- Models with a locking panel or a magnetic flap give you a way to close the opening at night or when you're away.
Let AZ Smart Fix handle it
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Frequently asked questions
Can a pet door go in any door?
Most solid and hollow-core doors can take a pet door, though hollow-core doors need the cut edges reinforced so the frame has something to grip. Metal and glass doors are special cases. We'll confirm your door works before cutting.
Is it better to put the pet door in a door or a wall?
A door panel is simpler and quicker; a wall install opens up placement options and can route the pet where you want. A wall cut is more involved because of framing and checking for utilities, so the right choice depends on your layout.
How do I keep drafts and rain out?
A properly sealed frame and a flap that closes fully are the basics, and many units add weatherstripping or a magnetic seal. We seal the perimeter with exterior-rated sealant so the opening doesn't leak air or water.
What if my pet is still growing?
For a puppy or kitten we factor in the expected adult size so you're not cutting a second, larger opening later. If the breed's grown size is uncertain, we'll talk through sizing before any cutting.
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