Cat doors provide your cat with easy access to both your home and a safe outdoor area. You can buy cat doors from a pet supply store or department store. You can also make homemade cat doors out of things that you have around the house. Homemade cat doors are easier to construct, cheaper and easier to use than store-bought cat doors.
Mud Flap Rubber
Construct homemade cat doors out of mud flap rubber. Buy a set of mud flaps for a car or truck, or take some that you already have. Cut a cat-sized door in your wall or your existing door. Cat doors are no more than 1 foot tall and 8 inches wide. Take two mud flaps and lay them up against the hole. The mud flaps should overlap by half an inch. Use heavy duty staples, screws or nails to attach the mud flaps on all four sides of the hole. Poke your hand through the mud flaps several times, and then guide your cat through. Once he has learned how to shove his head through, he will be able to use the cat flap easily.
Cut a cat-sized door in your wall or door. Fold a regular garbage bag four times and fasten the top of the bag above the cat door with staples or nails. Fasten the bottom of the bag in the same manner. Use a sharp knife to slice five or six strips in the plastic. Show your cat how to push through the holes to get from one side of the door to the other.
Make homemade cat doors any size, but make sure that they have a lip of at least 2 inches from the bottom of the door or wall to the bottom of the cat door. This will help eliminate mice and rodents from running in the cat door, and will keep out dirt and leaves that might blow through. A high bristled mat on both sides of your cat door will help keep your home clean.