By Chris Williams on May 17, 2018.

I just noticed an irregular hole in a corner of one of the drop ceiling panels in my garage. It looks like something chewed an opening to get into, or out of, the ceiling void space. Would a mouse do that? I haven’t seen any other evidence like mouse poop. Would it come to a baited trap in the garage?

H. R., Fitchburg, MA

That could very easily be the work of a mouse or another rodent. Mice often end up in garages, usually thanks to worn or bad-fitting garage doors (see Maintain Your Garage Door to Keep Mice Out). From there they often move into wall or ceiling voids and into the house.

Mouse hole through asphalt shingle

I don’t know exactly what your ceiling panels are made of but a mouse (or rat, squirrel, other rodent) will chew on anything that is softer than the enamel on its teeth: wood, aluminum, lead, copper, plastic, vinyl siding, sheet rock, asphalt, even mortar. Rodents will gnaw on plastic, waxy materials, leather, cardboard, paper, even bars of soap.

Usually rodents gnaw to get to food, to get into a desirable space, or to create nest material, but sometimes they gnaw just because they can. They have no hesitation in enlarging an existing opening just enough to get their body through. A young mouse can squeeze through a crack or crevice that is only about ¼-inch high or the diameter of a pencil. If there is no existing opening, a mouse can start one from scratch if there is a rough surface or an edge that they can get a grip on to bite into.


Mouse hole with Rub Marks. Z. Ciras.

If a rodent is regularly using that hole in the ceiling, you might see evidence in the form of dark rubmarks around the opening. Oils and dirt in the rodents fur accumulate where they repeatedly touch surfaces and as they squeeze through openings. If the opening were in wood, the edges would gradually get darker and smoother with time as the mouse chews off rough pieces. On the other hand, if a mouse gained access to your ceiling voids or attic, it may be very happy moving around through wall voids and dropping in to the kitchen to grab bits of food, with no need to ever return to the garage. So a trap in the garage may or may not work.


Mouse nest in a car. Z. Ciras.

Having a mouse, or possibly many mice by now, running amok inside the voids of your home is not a good idea for many reasons. Rodents have a fondness for chewing on the insulated covering of electrical wires, requiring repairs at the minimum, and possibly causing fires in the extreme.

Give Colonial Pest a call and let one of our trained technicians inspect your home for evidence of mice. We can set up a monitoring program and if mice are present, we will institute a baiting or trapping program. Our technicians are experts and our work is guaranteed, so give us a call today!

These Colonial blogs give further information on mice living in wall voids:



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