I’ve been down the steel wool route too, and I had pretty much the same outcome—rust started showing up after the first winter. My attic’s relatively dry, but I think even a bit of humidity up there is enough to get steel wool going. I didn’t get any odors either, but I did notice some of that rusty dust trickling out when I checked the gaps a year later.
Copper mesh is interesting. I looked into it when I was sealing up some mouse entry points, since everyone says it doesn’t rust and rodents hate chewing through it. The cost, though… copper’s not exactly cheap these days. I ended up using it in a couple of spots where I had persistent gaps and so far, after two years, no rust or corrosion at all. It’s holding up better than steel wool, but it’s definitely not as budget-friendly if you’ve got a lot of area to cover. Also, it’s a bit stiffer, so getting a really tight fit in odd-shaped holes takes more effort.
I’m with you on the foam shrinking issue—no matter how carefully I layer it, there always seem to be new gaps after a season or two. Maybe temperature swings in the attic are making it contract more than expected? I tried using backer rod in larger gaps before foaming, which helped cut down on how much foam I needed and seemed to reduce shrinkage a bit. Not perfect, but better than just foam alone.
Has anyone tried those stainless steel pads instead of regular steel wool? Supposedly they don’t rust either, and they’re a lot cheaper than copper mesh, at least from what I’ve seen online. Curious if they hold up as well or if they’re still prone to breaking down over time.
- Tried the stainless steel pads (the kind for scrubbing pots, right?) in a couple spots last fall. They *seem* to be holding up—no rust yet, but it’s only been one winter. I’m not convinced they’ll last as long as copper, though. The strands are thinner and I noticed a few started to unravel when I stuffed them in tighter gaps. Not a dealbreaker, but something to watch.
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“I tried using backer rod in larger gaps before foaming, which helped cut down on how much foam I needed and seemed to reduce shrinkage a bit.”
I did the same thing and yeah, it helps, but I still get those weird little cracks after a while. Maybe it’s just the attic doing its thing with all the temp swings.
- Copper mesh is great, but my wallet cried a little when I priced out enough for the whole attic. Ended up mixing materials—copper for the worst spots, stainless pads for the rest. Not perfect, but better than steel wool dust everywhere.
- If anyone’s expecting a miracle fix, I’d say don’t get your hopes up. Everything seems to have a tradeoff—cost, durability, or just plain hassle. Welcome to homeownership, I guess...
- Stainless pads: yeah, those are the pot scrubbers. I used them in a few soffit gaps last year—noticed the same thing with unraveling if you jam them in too tight. Not sure they’ll last more than a couple seasons, but way less messy than steel wool.
- Backer rod + foam: works okay for me, but I still get cracks when temps swing hard (Midwest attic here). Wonder if it’s just the nature of spray foam in weird spaces.
- Copper mesh is awesome but man, that price tag... I did a mix too. Honestly, I’d rather patch things up every few years than drop $$$ all at once.
- Anyone tried using natural fiber insulation or something more eco-friendly in these spots? Curious if there’s a green option that actually holds up.
Copper mesh is the gold standard for critter-proofing, but yeah, it’s a wallet-buster. I see a lot of folks mix it up with stainless pads or even just heavy-duty steel wool, but like you said, those stainless ones can unravel or rust out quicker than you’d think, especially if they’re crammed in tight. I’ve seen some pretty creative “patch jobs” during attic inspections—everything from scouring pads to old t-shirts stuffed in gaps. Usually doesn’t last long.
Backer rod and foam can work, but you’re right about the cracking. Midwest temps are brutal on anything that expands and contracts. I’ve seen foam split away from framing after a couple seasons, especially if it wasn’t applied in ideal conditions. Sometimes it almost seems like more trouble than it’s worth in tricky spots.
As for the eco-friendly stuff, I’ve come across folks trying sheep’s wool or cellulose in small gaps, but rodents love chewing through that. If you’re dealing with pest entry points, I’d steer clear of anything they might see as nesting material. For actual insulation, sure, but for blocking critters? Not so much.
Copper mesh is definitely pricey, but I’ve seen way too many steel wool patches turn into rust stains or just plain disappear after a wet season. I’m with you on the foam too—looks solid at first, then you check back a year later and it’s cracked or pulled away from the wood. Midwest freeze-thaw cycles just chew up anything that isn’t flexible enough.
I’m curious—has anyone tried using hardware cloth (that 1/4" galvanized wire stuff) for these gaps? It’s not as easy to shape as mesh, but I’ve had decent luck stapling it over small holes, then sealing edges with caulk. Not perfect, but it holds up better than steel wool in my experience. Wondering if that’s overkill or if there’s a downside I’m missing... rodents haven’t chewed through it yet, but maybe I’ve just been lucky.
Also, has anyone had luck with those expanding pest-block foams? I keep seeing them at supply stores, but not sure if they actually last longer than regular spray foam when temps swing hard.
