expanding foam is basically mouse confetti... they love tunneling through that stuff.
Couldn’t agree more—expanding foam is a joke against rodents. Hardware cloth’s the way to go, but I’d argue you need to double up in some spots. Mice are relentless, especially when it gets cold. I’ve seen them squeeze through gaps you’d swear were airtight. Cardboard and duct tape? Been there, done that... but nothing beats a solid metal patch if you want to sleep at night.
Metal patching is the only thing that’s ever held up in my experience. I’ve been called out to crawlspaces where folks tried everything—foam, steel wool, even a bit of chicken wire—and the mice still found a way through. One guy had stuffed every gap with expanding foam thinking it was “rodent proof.” Six months later, there were tunnels like a hamster cage.
I’ll admit, I used to think steel wool could do the trick if you really packed it in, but those little suckers will chew right around it if they’re determined enough. Hardware cloth is solid, but yeah, double it up at corners and anywhere pipes come through. Mice have a sixth sense for weak spots, especially near old heater vents or where someone got lazy with the caulk.
Cardboard and duct tape just make their lives easier. If you want a real fix, sheet metal and screws are the way to go. Might not look pretty, but you’ll actually keep warm without sharing your house with a mouse family.
I get the whole “sheet metal or bust” thing, but honestly, I’ve had decent luck with a combo approach that doesn’t break the bank or require a tetanus shot. Here’s my two cents:
1. Steel wool *plus* caulk. Stuff the steel wool in deep, then seal over it with a thick bead of silicone caulk. The caulk keeps the wool in place and makes it less appealing for mice to mess with. It’s not Fort Knox, but it’s held up for me in a 100-year-old house with more gaps than insulation.
2. For bigger holes, I’ll use hardware cloth (the 1/4” stuff), but instead of sheet metal, I just staple it tight and then slap some duct seal putty around the edges. Not pretty, but it’s cheap and you don’t need power tools.
3. If you’re desperate, peppermint oil on cotton balls actually seemed to slow them down for a while—at least until I could patch things up properly.
Not saying metal isn’t the gold standard, but sometimes you gotta work with what you’ve got in the junk drawer.
Not saying metal isn’t the gold standard, but sometimes you gotta work with what you’ve got in the junk drawer.
Honestly, I’m all for skipping the sheet metal if it means less waste and fewer trips to the hardware store. I’ve done the steel wool + caulk trick too—works fine, and you don’t end up tossing a bunch of sharp scraps. Hardware cloth is decent, but I’d swap duct seal for some eco-friendly clay or even old denim scraps if you’ve got ‘em. Mice hate that stuff, and it’s one less thing in the landfill. Peppermint oil? Yeah, it’s a band-aid, but at least your house smells better than the neighbor’s.
You’re speaking my language—sometimes you just gotta MacGyver it with what’s in arm’s reach. I’ve patched more than a few holes with steel wool and caulk, and honestly, it holds up better than folks give it credit for. Old denim scraps? That’s a new one for me, but I can see how that’d work. Plus, it’s way less itchy than fiberglass.
I hear you on the peppermint oil. It’s like putting a pine tree air freshener on a leaky exhaust—doesn’t fix the problem, but at least it smells festive while you figure out a real solution. Hardware cloth is solid, but man, cutting that stuff up is a pain if you don’t have the right snips.
End of the day, whatever keeps the critters out and the heat in is a win. No shame in getting creative, especially if it means fewer trips to the store and less junk tossed out.