A bunch of puppies and a cat try to break into a house. Cat Doors and Flaps Let your cat come and go with ease. With a cat door featuring a lockable flap, they can roam from indoors to out, be contained to a specific area while you're away or freely travel throughout your home. Stopping access to the outdoors can help keep your cat safe from predators and cars; keeping your cat from bedrooms can help reduce human allergies and ensure a good night's rest; and keeping your kitty out of pantries, basements and garages can prevent injury or accidental ingestion of harmful substances. Training your cat away from pushing open doors can serve several useful purposes. Do your pets get along? Friends For LifeQuilty the cat is quite the character. That is until a cat figures out how to open the door. Installing a cat door can be a simple DIY project to let your cat have access to multiple areas of your house and yard. A cat has gained quite the notoriety after his many escapades at the shelter. He likes to open doors and let other cats out of the room to infiltrate the lobby.