I get what you mean about the “forever” fix, but I’m not totally sold on replacing the IGU every time. In my last place, I lived with fogged panes for years and honestly, it didn’t bother me much except in winter. Do you think the energy savings from better coatings actually make up for the cost? I’ve always wondered if it’s just marketing hype or if folks really notice a difference on their bills.
Honestly, I get where you’re coming from about just living with the fogged glass. If it’s only a little annoying in winter, I can see why you’d just shrug it off and not rush to replace the IGU every single time. I’ve seen plenty of folks do exactly that, especially if the windows aren’t in a main room or you’re not too fussed about the view.
But here’s the thing—when it comes to those newer coatings and the supposed “energy savings,” it’s not just marketing fluff… but it’s also not always a night-and-day difference on your monthly bill, either. I’ve put in a lot of low-E and argon-filled units for people who swear their rooms feel more comfortable, especially in places with big temperature swings. The glass does a better job keeping the heat in (or out), and you can sometimes feel the difference just standing next to the window in January or July. But if you’re expecting your heating bill to get cut in half, that’s probably not happening unless you’re replacing a whole house full of old, leaky windows.
For me, the bigger factor is comfort and condensation. Once the seal’s shot, you start getting more drafts and sometimes even moisture problems around the frame. That’s where the cost can creep up—if you let it go too long and end up with mold or wood rot. I had a client last year who ignored a couple of fogged units for years, and by the time we took them out, the sills were a mess. Ended up costing way more than just swapping the glass.
Long story short, if you’re fine with a bit of fog and it’s not causing other issues, I don’t blame you for waiting. But if you’re already feeling the cold more in winter or you see moisture building up, it might be worth biting the bullet. The coatings help, but the real win is just having a tight seal again.
And yeah, I’ve noticed a small drop in my own bills after upgrading, but nothing earth-shattering. I mostly just like not seeing my breath when I walk past the window in February...
- Totally hear you on the “not earth-shattering” energy savings. I put in a couple low-E panes last fall and yeah, my bill’s maybe $10/month lower, but the real win is not having to wipe condensation off the sills every morning.
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“if you let it go too long and end up with mold or wood rot. I had a client last year who ignored a couple of fogged units for years, and by the time we took them out, the sills were a mess.”
This hits home—my neighbor waited and ended up with a science experiment growing in his window frame. Not pretty.
- If it’s just a spare bedroom or basement, I’d probably wait too. But if your socks start sticking to the floorboards from moisture? Time to swap that glass.
I get the concern about mold and rot, but honestly, I’m not sure it’s always worth rushing to replace foggy panes right away. My windows started fogging up last winter and I just keep a dehumidifier running—so far, no musty smells or soggy sills. Maybe it depends how bad the seal is busted, but sometimes I feel like the urgency gets overstated unless you’re already seeing water damage.
I just keep a dehumidifier running—so far, no musty smells or soggy sills.
That's been my approach too. My kitchen window's been foggy for two years now and honestly, nothing's gotten worse. I'm curious though—does anyone know if leaving it like this affects energy bills much? I haven't noticed a big change, but maybe I'm missing something.
My kitchen window's been foggy for two years now and honestly, nothing's gotten worse.
I totally get the temptation to just leave it—my old living room window fogged up and I ignored it for ages. But here's the thing: once the seal is gone, that window isn’t really insulating like it should. Even if you haven’t noticed a spike in bills, heat (or AC) can sneak out way easier through that gap. Sometimes it’s subtle, especially if it's just one or two windows, but over time it can add up.
What I did was a little test—on a cold day, I stood by the foggy window and compared how chilly it felt compared to my other windows. There was definitely a draftier feel. If you want to be thorough, you could try using one of those cheap infrared thermometers to check for temperature differences around the panes.
Dehumidifiers help with moisture in the air, but they won’t fix the broken seal or restore the insulation. If energy efficiency is your thing (it is for me), eventually swapping out that foggy unit might save you more than you’d think—even if the change isn’t super obvious on your bill at first.
Yeah, I’ve noticed the same thing—one foggy window doesn’t seem like a big deal at first. But after a while, the drafts really do creep in. I swapped out a couple in my place last winter and was surprised how much less chilly that corner felt. One thing people don’t mention: sometimes you get a bit of mold or gunk building up inside the glass if it’s left too long. Not always, but worth checking for. Replacing just the pane (not the whole window) can be cheaper than most folks expect, especially if you’re handy with tools.
Yeah, that’s spot on about the mold—left mine too long once and it was a mess to clean out. I’ve found it’s usually just the seal that fails, not the whole window, so swapping the glass unit is way easier (and cheaper) than folks think. Did one last fall with a buddy and honestly, the hardest part was wrangling the old glazing out. If you’re comfortable with a putty knife and don’t mind a little mess, it’s totally doable. Just watch for hidden rot in the frame... learned that the hard way.
That’s really helpful to know it’s usually just the seal that fails. I’ve been worried I’d have to replace the whole window if mine started fogging up. When you swapped out the glass unit, did you order a custom size or were you able to find something standard? I’m curious if older windows make that trickier—my house is from the 70s and nothing seems quite square anymore... Also, how did you spot the hidden rot? I’d hate to miss something like that and have to redo the work later.
That’s a legit concern, especially with a house from the 70s—things aren’t always square, and “standard” sizes can be wishful thinking. I usually end up measuring each opening and ordering custom glass units, just to be safe. It costs a bit more, but it saves a ton of headaches. For hidden rot, I poke around with a screwdriver after pulling the stops—if it sinks in or the wood feels soft, that’s a red flag. Sometimes you don’t see it until you’re halfway in, though... Old houses keep you on your toes.