- Purrfect Fence This is simply THE BEST FENCING FOR CATS! Domestic cats can be trained to stay indoors. Noise aversion is the best method. If you have an aluminum screen door, give it a good bang before going in or use a can full of pennies or other noise maker. Most cats are afraid of the loud noises and stay away from the door. Some recommend keeping a squirt bottle near the door and use it. If your cat is permitted outdoors, the cat should be in a harness, enclosure or use fencing such as Purrfect Fence. Never leave a cat outdoors unattended.