Squirrels are entertaining, cute and fun to watch--except when they are chewing on the side of your house or causing havoc in other parts of your house. Whether it's gray squirrels, fox squirrels or other tree squirrels gnawing on the siding, making them stop can be a challenge. When one approach doesn't work, remain as persistent as these creatures are, until you have fully protected your wood siding from damage.
Prevent squirrels' easy access to your house. Block holes, cracks and other entrances to your attic and basement to stop nest-building activities. Place lightweight plastic piping over utility wires that run to your hose; the plastic rotates on the wire under a squirrel's weight, stopping it from getting to the siding from above.
Crush mothballs and sprinkle the pieces on the ground next to the wall where the squirrels gnaw. The chemical naphtalene in the mothballs is a temporary deterrent, most effective if applied as soon as any signs of gnawed siding are spotted and replaced with freshly crushed mothballs after rain.
Apply a taste repellent to the side of the house. Spray capsaicin, a natural extract of hot peppers, on the chewed areas and in a 2-foot circumference surrounding the spot. An alternative is commercially available repellent containing Thiram, a chemical that is highly distasteful to squirrels.
Brush a thick layer of polybutene, a sticky material, onto the edge of the roof and downspouts to discourage squirrels from climbing to eat the siding. Apply polybutene directly to the siding surrounding the areas where squirrels gnaw and re-apply the substance frequently to keep it tacky and sticky.
Trap squirrels that continue eating siding in spite of modifications and repellents. Use a wire cage trap at least 9 inches by 9 inches square and 2 feet long with doors on either end. Set the trap near the wall the squirrels are chewing, with a clump of peanut butter or nuts inside. Once a squirrel is captured, transport it to an uninhabited area far away from your house for release into the wild.