Doggy doors can be installed into most doors including doors made from solid timber, hollow core timber, steel and glass (although a glazier would need to cut a hole in the glass). Doggy doors can even be installed into brick walls and screen doors.

Doggy Doors are available at some hardware stores but large pet shops usually have a greater variety.

STEP BY STEP

NB: If the door has to be removed to work on it lay it over a pair of trestles in your garage or outside patio area.
1 Measure the height from the ground to the underbelly of your dog.
2 Transfer this measurement onto the outside of the door. This will be the bottom of the doggy door. Position the doggy door so that the bottom of the door is along the line you have just marked. Using the doggy door as a template, mark all the sides of the inside of the door.
3 Drill a hole in each corner of the doggy door space and then use a small saw to cut out the doggy door.
4 Sand edges.
5 Reposition the doggy door and screw into place.

NB: Remember, by creating another entry into the home you need to think about safety against burglary. It is better to install the doggy door at the back the house rather than the front where it can be seen from the street.