If you've ever thought you could mouse-proof or rat-proof your house by sealing up small gaps around the outside, forget it. Mice can squeeze through spaces as small as a nickel, and rats need a space only twice that size to find their way into your home.
Mice and rats are great climbers and jumpers, too: mice can leap 12 inches into the air and hop down from the same height without injury, and rats can leap 36 inches vertically and jump off of a 50-foot-tall building without a scratch.
Fortunately, there are a number of ways you can make your house a much less welcoming place for mice and rats:
Avoid nesting sites: Stacks of newspapers, cardboard boxes, firewood, lumber and other storage encourages nesting. Keep all storage off the ground or floor at the inside and outside foundation perimeters of your home, and make sure all bushes, hedges and other plantings are trimmed back and well away from the foundation.
Secure storage: Mice can squeeze through spaces as small as a finger, so seal up potential entrances with sheet metal, steel wool or cement. Pay particular attention to the spaces around pipes, vents and ducts when rodent-proofing your home.
Keep a clean house: Wash dishes and cooking utensils immediately after use. Keep counters and floors free of soiled food, and clean the insides of cabinets and pantries frequently to avoid feeding furry creatures.
Use rodenticides: Poisons designed to eliminate mice and rat infestations are safe and highly effective if used in accordance with label instructions, and can help to mouse-proof your home. If exposure to children or pets is a concern, use lockable bait stations; with these, the poison is secured inside a container that has holes small enough for only a mouse or rat to enter.