Summary: Tips on how to stop mice from entering your home, plus steps to take once you have mice in the house.
Jen, Vancouver, Canada asks:
I have a hundred year old three-story house with a concrete foundation and partially finished basement, and for many years we have had a problem with mice. We trap them, but every fall when it gets cold, more come in from outside. Because they mostly live in the walls and ceilings, closing up the holes inside the house is not a viable option. I was wondering whether there is any way of sealing the house at ground level from the outside, so that they wouldn't be able to get in. Is this viable, and who should I call to have such a thing done? A mason? An exterminator? Thanks!
I, too, live in a 100+ year old home. Fortunately, I do not share your problem, but I can relate.
You can stop mice from getting in the house, but not without some effort on your part. Understand that mice look for places they feel protected. Inside the walls of your house is perfect. So, let's talk about how to discourage the mice from entering in the first place.
I'm taking an educated guess your house backs up into a wooded area. If that is the case, I would also guess that there are tall grasses and high weeds growing along the edge of the woods. These would be excellent areas where mice live in the wild. As mice explore their surroundings, their natural curiosity may have them exploring along the foundation of your house. Of course, as they run along the foundation walls, any holes with openings the size of a dime presents an opportunity for entry. Don't overlook the openings where electric conduits enter the house or where hose bibs and water lines come through the foundation. Repair bad thresholds under doors and garage doors.
Mice love places to hide. Take a look along the foundation and be sure to cut down high grasses. Move stacks of wood away from foundation walls, as well. Birds are messy eaters, dropping lots of seed on the ground, so move bird feeders well away from the house. Bowls of pet food will also attract hungry rodents. Leaf litter and any other clutter needs to be removed.
A good mouse program sometimes requires a first-line of defense. The placement of rodent stations along the outside perimeter wall may be called for. I would suggest one rodent station every twenty five feet. You can get rodent bait stations disguised as landscape rocks online. These stations can be secured to the ground to prevent tampering.
As for the mice already residing inside the house, I would suggest snap traps and glue boards. Mice are easy to catch if you know how. Please read my articles on mouse proofing, mouse infestations and how to catch a rat.
I think a good brick layer can do tuck pointing and a garage door company can put a rubber seal on the bottom of the door. The installation of a high quality sweep on the bottom of pedestrian doors will also do the trick.
Hope this information helps.
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