Plastic film’s the way to go if you’re dealing with aluminum windows sweating, especially in older homes. I’ve worked on a bunch of places from the 60s and 70s, and those frames just don’t hold heat the way newer ones do. Every winter, I see folks get frustrated—wipe down the glass every morning, towels on the sill, you name it.
Here’s what I tell people: first step, check your humidity. Doesn’t matter how good your windows are, if you’re running a humidifier or cooking pasta every night without the vent fan, that moisture’s gotta go somewhere. I’ve seen kitchens where the windows drip like crazy just from boiling water with no fan on.
Plastic film over the window interior does help, but yeah, it’s a pain to put up every fall. I use a hair dryer to shrink it tight—makes a real difference. Foam strips don’t do much for condensation itself; they’re more about stopping drafts. If you want less fuss, look for those magnetic interior storm panels. Not cheap, but easier to take off and put back on than the film.
One job last winter, I found black mold behind the trim—client had ignored wet sills for years. If you see soft wood or black spots like someone mentioned above, don’t wait. That’s when you need to pull the trim and check for rot. Otherwise, just keep an eye out and wipe things down. Aluminum frames will always sweat some in cold weather because they’re such good conductors.
I’ve never seen a perfect fix short of swapping out the windows for something with a thermal break, but that’s a big investment. Until then, control humidity and seal up what you can. It’s more about managing than eliminating it completely.
You nailed it—managing condensation on old aluminum windows is just an ongoing thing. I’ve been in and out of houses from that era, and honestly, I’ve never seen a silver bullet fix unless someone wants to rip out all their windows for something modern (and yeah, most people don’t).
“Plastic film over the window interior does help, but yeah, it’s a pain to put up every fall. I use a hair dryer to shrink it tight—makes a real difference.”
Totally agree. It’s not glamorous, but the film does help cut down on the sweating. I always tell folks: if you’re going to do one thing, do the plastic film right. The hair dryer trick gets it nice and tight so you’re not staring at wrinkly plastic all winter. Those magnetic panels are slick but cost way more than the film kits—they’re worth it if you hate reapplying tape every year or have fancy trim you don’t want sticky stuff on.
One thing I’ll add—sometimes people go overboard chasing drafts with foam strips and weatherstripping, thinking it’ll solve the moisture issue. Like you said, that’s more about stopping cold air leaks, not condensation itself. If your humidity’s high inside, the water’s still gonna show up somewhere cold.
I’ve seen too many sills rot out because folks just accept wet wood as normal. If you see black spots or soft patches, don’t wait around. Pull that trim and check for damage before it turns into a bigger headache.
If you can’t justify new windows, keeping humidity in check and using window film every year is about all you can do. It’s a hassle, but better than dealing with mold or replacing rotten framing later on. And hey, at least it’s only a few months out of the year...
The plastic film trick is a total lifesaver, even if it makes my living room look like I’m prepping for a science experiment every November. I actually forgot to use the hair dryer the first time—learned that lesson real quick when the cat started playing with the saggy corners. I will say, messing with humidity is a pain. We got a cheap hygrometer and it’s wild how much cooking pasta or running the shower bumps up the numbers. Not glamorous, but at least my window sills aren’t growing mushrooms anymore...
Man, the plastic film brings back memories. I’ve been in so many homes where folks have tried every trick to keep those windows from sweating. The hair dryer step is key—seen a few “bubble windows” when folks skip it. Humidity’s a beast, though. I remember one winter, a client’s kitchen window would drip like crazy after every spaghetti night. Ended up putting in a vent fan, which helped, but honestly, sometimes it just comes with the territory if you’ve got older aluminum frames. At least you’re not growing mushrooms anymore… that’s a win in my book.
Plastic film is a classic move—nothing like that crinkly sound when you tap the window in January. I’ve done the whole routine: tape, stretch, then blast it with the hair dryer until it’s drum-tight. Still, with old aluminum frames, sometimes it just feels like you’re fighting nature. I tried running a dehumidifier one winter and my electric bill almost made me cry. At least if there’s no more mushroom farm on your sill, you’re ahead of where I was a few years back...
Still, with old aluminum frames, sometimes it just feels like you’re fighting nature.
Totally get this. I’ve done the plastic film routine too—hair dryer and all. One trick I found helpful: put a rolled-up towel on the sill overnight to catch drips. Not pretty, but it saves the paint. I also tried cracking the window just a bit in the morning to let out humidity—works okay if you don’t mind a chill.
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— Yep, I’ve done this too. Not glamorous but it works.put a rolled-up towel on the sill overnight to catch drips
- If you’re getting tired of the plastic film, I found running a small fan near the window in the morning helps move the air and dries things out faster.
- I tried leaving the window cracked, but in January? No thanks... The chill just isn’t worth it for me.
- If you have those old storm windows, sometimes popping them open for a few minutes midday helps clear moisture without freezing out the room.
Plastic film and towels definitely get the job done, but man, do they get old after a while. I always tell folks—aluminum windows are notorious for sweating because they’re such good conductors. Heat just zips right out, cold comes in, and boom: condensation. The fan trick is smart, though I’ve found it only helps a bit if the humidity inside is high.
I’ll admit, I’m not a fan of cracking the window in winter either. Tried it once, and the room felt like a meat locker for hours. The storm window trick works best in my experience, but not everyone has that option, especially in newer places. Has anyone tried using a dehumidifier in the room? That’s what finally tipped the scales for me—less moisture in the air, less “morning sweat” on the glass.
Curious if anyone’s actually upgraded to newer windows because of this. Was it worth the hassle and cost, or did you just end up with different problems?
That’s a solid rundown of the options. I hear you on the plastic film and towels—after a few winters, it just feels like a never-ending chore. The fan trick only ever made a dent for me if I kept the humidity low, but with a bunch of people or pets in the house, that’s an uphill battle.
I actually did pull the trigger on new windows last year—went with double-pane vinyl to replace the old aluminum. Not gonna lie, it was pricey and a bit of a hassle (had to coordinate with the installer around some weird framing in my place). But the condensation issue pretty much vanished overnight. The room feels warmer too, and my heating bill dropped a bit. Only downside? The outside noise is muffled now, which is great most of the time... but I kind of miss hearing rain on the metal frames.
Dehumidifier’s definitely a good call if new windows aren’t in the cards yet. You’re right that it makes a noticeable difference, especially in stuffy bedrooms. All things considered, there isn’t really one magic fix—it’s all about stacking up small improvements until you get the result you want.
The room feels warmer too, and my heating bill dropped a bit. Only downside? The outside noise is muffled now, which is great most of the time... but I kind of miss hearing rain on the metal frames.
Funny how you don’t realize you’ll miss those little things till they’re gone. I swapped out my old aluminum sliders a couple years back—same deal with the condensation just disappearing. But yeah, coordinating the install was a circus act. Still, waking up without puddles on the sill is worth missing the pitter-patter soundtrack. Dehumidifier helped before, but honestly, it was just buying me time.