After a mouse infestation, do you recommend removing and replacing the blown-in insulation? Should we be concerned about our health?—Gerald Fluge, via email
If you believe that the insulation has been compromised—if it’s saturated with urine; if it’s riddled with mouse droppings; or if there’s other evidence of mice damage—then absolutely, it should be removed, says Bill Hughson, the owner of Pro-Wildlife Services in Lindsay, Ont. It’s definitely a health hazard. (Mice harbour infectious agents, such as hantavirus; humans can contract disease from inhaling airborne virus particles from urine and feces.) “And when mice start burrowing in and tampering with your insulation, that’s reducing its R-value,” he says.
How to clean up after a mouse infestation
You can remove the insulation yourself, but you’ll want to wear protective gear—at least gloves and a mask (for safe cleaning tips, see “Your Guide to Cleaning Just About Everything at the Cottage”). You can also hire a company to remove the insulation. They have equipment for the job. “We’ve got a large insulation vacuum that’s actually specifically designed to vacuum all that stuff up,” says Hughson. “For an attic, we can bring the hoses up through a roof vent or up through the soffits.”
Next, you’ll need to replace the insulation. But with what? “I generally recommend mineral wool insulation, such as Rockwool,” says Lauralee Proudfoot of Cottage Country Pest Control in Victoria Harbour, Ont. To make it, molten rock is spun like cotton candy into fibres and formed into batts. “Rodents don’t seem to like it the same way they do the pink insulation, or the cellulose blown-in stuff. We call the cellulose stuff ‘bedding.’ ”
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Hughson, on the other hand, suggests high-density spray foam. “It’s harder for rodents to chew through.” Harder, not impossible. And no matter what insulation you choose, it won’t prevent future mouse problems, he says—not if you don’t stop them from getting into your cottage. “If the infestation’s been so high that you have to start removing insulation, then I would be really focussed on exterior rodent-proofing.”
Got a question for Cottage Q&A? Send it to answers@cottagelife.com.
This article was originally published in the June/July 2025 issue of Cottage Life.
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