Mice in Your Attic by the Barrie Home Inspector
Most people never know they have mice in their attic until they have a home inspection. In the Barrie area I would estimate that 95% of the brick homes inspected with fiberglass or rock wool insulation have signs of rodents living in the attic. Some attics have so many trails through the insulation it looks almost like a normal pattern. Home buyers are surprised to learn that mice can climb brick walls with ease and only need a gap of 1/4 inch to gain entry into your attic. Come winter time your warm cozy attic would seem like Florida to a mouse.
The average mouse has about 5 to 10 litters in a year and it only takes a month for the young mice to become independent. If left un-checked your attic could easily become overrun with mice. Since mice are nocturnal you may even catch sight of one entering your attic area around dusk when they will be out foraging for food and water. Your attics is a desirable location to a mouse. Attics are protected from the elements, are free from predators and are much cleaner than the hole in the ground their less fortunate mouse-cousins live in.
The three methods of preventing or getting rid of mouse problems is to seal, trim and trap.
Seal – Go over the complete exterior of your home, paying particular attention to any dark areas, and seal any gap 1/4 inch or larger. Heavy materials are recommended such as mortar, sheet metal or heavy gauge hardware cloth. Use a powerful flashlight to illuminate any dark areas, if it stays black then it is a hole, which requires sealing.
Trim – Trim tree limbs at least 4’ away from roofs, attic vents, eaves, and utility wires. Trim and thin ground covers and allow approximately 12 inches of open area under plants.
Trap – Trapping is an effective means of controlling rodents. Snap and glue traps can be purchased at nurseries and hardware stores and are most effective when placed in rodent runways between harborage and feeding areas. There are many scams out there which claim to rid your home of mice. Ultra sonic wave devices, although sellers claim success, most studies have found them completely ineffective. Using poison or bait can also leave your attic with rotting carcasses. Most experts agree that placing your trap near entrances and pathways will produce the best result.
Mice an carry up to 30 diseases which can affect humans and pets alike. To clean up your attic after removing mice mix a biocide solution, whether commercial or bleach water at the ratio of 10 parts water to one part household bleach. Enter the attic and, wearing a HEPA filter mask, use a spray bottle or similar to douse the insulation surface and any objects where mouse droppings are present. Wait a few minutes. Not only does water help weigh down microscopic particles that become airborne when disturbed, but the bleach or disinfectant kills germs, viruses and bacteria on contact.