Finally got my attic temps under control - here's what worked

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.”

- 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.

- Hardware cloth is tough, but I’ve seen determined mice squeeze through anything bigger than 1/4". If you’re just covering gaps, it’s fine, but for actual holes, I’d double up or use a finer mesh behind it.
- Galvanized stuff holds up better than steel wool, but in damp attics, even that can corrode over a few years.
- Pest-block foam? Tried it twice - looked good for a season, then shrank and cracked where temps swing hard. Not much better than regular foam in my book.
- Honestly, nothing’s perfect in Midwest freeze-thaw. Sometimes feels like you’re just buying time till the next round of repairs...

That’s pretty much the story with Midwest attics - nothing really lasts forever up there. I’ve seen folks use hardware cloth thinking it’s a one-and-done fix, but like you said, mice are relentless. Anything bigger than a quarter inch and they’ll find a way. I usually recommend layering 1/4" cloth with a finer mesh behind it, especially around soffits or where pipes come through. It’s not pretty, but it slows them down.

Galvanized is better than steel wool, but even that’s just buying time in a damp attic. I’ve pulled out plenty of rusted mesh after just a few seasons. Steel wool’s even worse - once it gets wet, it’s basically mouse bedding.

Pest-block foam always looks promising at first, but I’ve seen it shrink and crack every time temps swing. Sometimes I’ll use it as a backing, but never as the main barrier. Honestly, you’re right - freeze-thaw cycles just chew through everything. Best you can do is keep up with inspections and patch as needed. It’s a maintenance game, not a permanent fix.

That’s been my experience too - no matter what you put up there, the critters and weather always seem to win eventually. I tried the pest-block foam last year and it looked solid for a while, but by spring it was all cracked and chewed. Layering mesh like you mentioned definitely slowed things down for me, even if it’s not perfect. It’s kind of reassuring to hear I’m not the only one patching things up every season.

Yeah, foam alone just doesn’t cut it long-term. I’ve seen rodents chew right through it, and weather breaks it down faster than you’d think. Heavy-gauge hardware cloth over any gaps has held up best in my experience, even if it’s a pain to install. It’s kind of a never-ending battle, but at least the attic stays sealed longer that way.

That hardware cloth is a lifesaver, even if it’s a pain to cut and fit around weird angles. I’ve tried just stuffing steel wool in the gaps before foaming, but it rusted out after a couple seasons and the mice came right back. Did you use staples or screws to secure the cloth? I’ve heard some folks double up with both, but I’m not sure if that’s overkill or just smart.

I went with screws and washers for the hardware cloth, mostly because I got tired of the staples popping out every time I bumped the mesh or tried to pull it tight. Maybe I was using the wrong kind of staple gun, but it just felt like a losing battle. The screws took a little longer, but once they’re in, that stuff isn’t going anywhere. I did try doubling up in a couple spots where the gaps were bigger or I was worried about critters getting clever, but honestly, for most of it, just the screws held fine.

Steel wool was a disaster for me too - looked solid at first, but after a year it was just a rusty mess and the mice basically laughed at it. Hardware cloth is a pain to cut, especially around pipes and weird corners, but I’d rather wrestle with that than deal with another mouse invasion. Overkill? Maybe. But after chasing mice out of the attic at 2am, I’ll take overkill every time.

- I’ve had some luck with heavy-duty staples, but only when using a pneumatic stapler - not the hand-held kind. Those manual ones just don’t have enough oomph for hardwood framing, in my experience.
- Screws and washers definitely hold better, but I found it tricky around tight corners or where there’s not much wood to bite into. Sometimes the screw heads can snag insulation or snag your hand if you’re not careful.
- On the steel wool front, I agree - total fail in damp climates. But I’ve seen folks use copper mesh instead. Costs a bit more, but it doesn’t rust out and critters don’t seem to chew through it as fast.
- For cutting hardware cloth, tin snips work but I switched to an angle grinder for long runs. Less hand fatigue, though you’ve gotta watch for flying bits.
- Overkill? Maybe, but honestly, after seeing what mice can do to wiring (and the repair bills), I’d rather go extra secure too. Just wish there was a less brutal way to keep them out...

Screws and washers definitely hold better, but I found it tricky around tight corners or where there’s not much wood to bite into. Sometimes the screw heads can snag insulation or snag your hand if you’re not careful.

That’s a fair point - tight spots are always a pain. I’ve seen folks use self-tapping screws with low-profile heads in those areas, but even then, you risk damaging the vapor barrier or catching on loose fill. On copper mesh, I’ve inspected a few attics where it’s held up for years, even with high humidity. Still, it’s not foolproof if you’ve got determined rodents. Anyone tried stainless mesh as an alternative? It’s pricier, but I’m curious if it’s worth the extra cost for long-term peace of mind.

Stainless mesh is something I’ve looked at a few times, but I keep hesitating because of the price tag. I get the appeal - rodents are relentless and copper mesh can corrode over time, especially if you’re in a damp climate. I’ve seen copper do fine in most attics, but I’ve also had to patch a couple spots after a few years where it started to break down, usually where there’s more moisture or where critters really went at it. Stainless would probably last longer, but I wonder if it’s overkill unless you’ve got a serious pest problem.

About those tight corners: I hear you on the frustration. I’ve had to use construction adhesive in a few places where there just wasn’t enough wood for screws. It’s not perfect, but it’s better than nothing if you’re stuck. Low-profile screws are a bit of a double-edged sword - less snagging, but sometimes they don’t hold as well in soft or old wood. And yeah, the insulation snags are no joke. I’ve lost count of how many times I’ve ended up with fiberglass in my sleeves.

Honestly, there’s no perfect fix. Every attic seems to have its own set of headaches. If you’re dealing with determined rodents, I’d say stainless might be worth the extra money, especially if you’re already tearing things up and want to do it once and be done. But if you’re just patching a few spots and haven’t had major issues, copper or even galvanized mesh could be enough.

It’s always a bit of a gamble, but I guess that’s true for most stuff up in the attic. At least you’ve got your temps under control - that’s half the battle.