How Are Mice Getting Into My House?

By Chris Williams on November 12, 2015.

We’ve had a mouse problem in our house lately and my wife wants me to check the whole house to figure out where they’re getting in. I reluctantly plan to do a search with caulking gun in hand. The job is kind of overwhelming; can you give me an idea of the best places to look first?

W. H., Bow, NH

Failed rodent proofing when only spray foam was used to close holes. Z. Ciras

Rodent-proofing a home can be an overwhelming job since you’re looking for very small opening or gaps. At Colonial Pest, we can do that for you. We have a team of experts who specialize in rodent exclusion. They’ll check your home for potential entry points and will use quality materials to seal them. Not all openings can be simply caulked, some will require sheet metal, screen, weather-proofing or other specialty materials to make them truly rodent-proof. Guaranteed.

However, if you want to go it alone, below are the places that the Centers for Disease Control (CDC) suggests you check for gaps or holes that could allow a rat or mouse to enter. Mice can squeeze through a hole the size of a nickel, but they are fully capable of gnawing and enlarging any opening that is smaller than that.

Check These Places For Rodent Entry Points

  1. Inside, under, and behind kitchen cabinets, refrigerators, and stoves
  2. Inside closets in back floor corners
  3. Around the fireplace
  4. Around doors, especially basement or below-grade doors
  5. Garage doors, especially at the sides and the threshold below
  6. Openings around pipes under sinks and washing machines, and around pipes going to hot water heaters and furnaces
  7. Openings around conduits where electrical lines, cables, and gas lines enter your home
  8. Around floor vents, dryer vents, and crawlspace vents
  9. Inside the attic, especially around vents or where there have been roof leaks
  10. In the basement or crawl space
  11. Around basement and laundry room floor drains
  12. Between the floor and wall juncture
  13. Cracks around the exterior foundation or gaps where framing or siding meets the foundation

Exclusion materials at a garage door. Z. Ciras

When you need a break from searching for mouse holes, check out these other helpful Colonial blogs on rodent-proofing your home:

Photo credit: Wikimedia Commons



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