How to Install a Cat Door in a Hollow Core Door

A cat door, or any pet door, offers your companion animal the ability to move from indoors to outdoors or from room to room within the home.
Kitties want to come in when they are out; and go out when they are in. Installing a door saves you from repeated steps.Kitties want to come in when they are out; and go out when they are in. Installing a door saves you from repeated steps.
Commonly used in the interior of the home hollow core doors are made of two wood veneers held apart by a frame, creating a door with a hollow center. Installing a pet door in a hollow core door requires some additional steps to the standard cat door installation process.

Step 1

Cut the door opening on one side of the hollow core door. Mark the door opening using the template supplied with the cat door. Drill 1/4 inch holes at each corner and cut between them with a jig or saber saw.

Step 2

Drill holes through the veneer of the opposite side of the hollow core door from the inside aligning the corners with the corners of the first cut. Cut between the holes with a jig or saber saw from the outside of the door.

Step 3

Measure the gap between the veneers of the hollow core door. Rip, cut lengthwise on a table saw, a piece of wood to this exact width.

Step 4

Cut the ripped board into four pieces with two equal to the height of the pet door opening and two equal to the width of the pet door opening.

Step 5

Place the pieces between veneers of the hollow core door. Hold in place, that’s the tricky part, while running a 1/2 inch screw through the veneer and into the ripped board. The ripped boards serve as a brace to hold the veneers apart and also as anchoring points for the door cat door frame. Run two screws from each side into each of the four pieces around the door.

Step 6

Install the cat door in the opening according to manufacturer’s instructions. This usually involves attaching components of the door to each side of the hollow core door with a flexible segment hanging across the opening.

Things You Will Need

  • Cat or pet door
  • Drill with 1/4 inch bit
  • Jig or saber saw
  • 1 inch thick board
  • Table saw
  • 1/2 inch wood screws

About the Author

Keith Allen, a 1979 graduate of Valley City State College, has worked at a variety of jobs including computer operator, medical clinic manager, radio talk show host and potato sorter. For over five years he has worked as a newspaper reporter and historic researcher. His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines.