Definitely saw the same thing with the cure time. I used the kit on a drafty bedroom window and figured I’d done something wrong because it was still sticky after 24 hours. Ended up just leaving it alone, and by day three it was finally set. I’m guessing the “breathable” part means it’s slower, especially if your house is on the humid side. Still, I’ll take a slow cure over peeling or cracking down the line... as long as it holds up when things freeze.
That’s interesting, I had a similar thing happen with the bathroom window—took forever to lose that tacky feel. I’m in a pretty old house, so I wonder if the drafts and temp swings make it even slower. Did you notice any difference in how well it sealed after curing? Mine seems solid so far, but I’m curious if that slow cure actually helps it flex with the cold.
Yeah, I get what you mean.
—same here with the kitchen window last winter. Old house too, and it was like the sealant just didn’t wanna set with all the temp swings. Once it finally cured, though, it felt way sturdier than expected. I kinda think the slow cure let it settle in better, especially since my windows flex a bit when it gets cold. Not sure if that’s by design or just luck, but so far no leaks... so I’ll take it.“took forever to lose that tacky feel”
“I kinda think the slow cure let it settle in better, especially since my windows flex a bit when it gets cold.”
That’s interesting—never really thought about slow curing as a good thing, but it does make sense. I’ve always been impatient and tried to speed things up with a space heater or hair dryer. Not sure that’s actually helped, now that I think about it. For my front bay window, I followed the kit instructions to the letter, but the tackiness hung around for days. Maybe the drafts and cold just made it take longer to bond.
Here’s what worked for me, step by step: First, I cleaned the area with rubbing alcohol and let it dry completely. Then I applied the sealant, making sure not to overdo it (learned that the hard way—too much just oozes out). I taped plastic over it for a couple days to keep dust off. After about a week, it finally set. I’m starting to think patience is actually key with these old houses and shifting frames.
I do wonder if flexing windows are just something you live with in older places, or if it’s a sign I should be looking at the framing more closely. Either way, no leaks so far... but I’m keeping an eye on it.
I get what you mean about patience—waiting for sealant to cure drives me nuts, but it really does seem to make a difference. I tried speeding up the process once with a heat gun, and the edge cured too fast while the middle stayed tacky. Ended up having to scrape it out and start over. Now I just let it sit, even if it takes a week.
About the window flex, I’ve noticed the same thing in my place (built in the 40s). The frames shift a bit with temperature swings, especially in winter. I don’t think it’s always a structural issue, but if you start seeing new cracks or the frame pulling away from the wall, might be worth checking for rot or settling. Otherwise, I guess a little movement is just part of having an older house. Haven’t had leaks since doing the slow cure, but I still keep a towel nearby just in case...
Patience with sealant really is a test, isn’t it? I’ve seen so many folks try to rush it—sometimes even pros get tempted—and it almost always leads to that half-cured, gummy mess you described. Heat guns or hair dryers just don’t get the job done evenly, especially if there’s any depth to the bead. Honestly, I’m not convinced there’s any shortcut that doesn’t risk making more work down the line.
The flex in older window frames is tricky. Like you said, some shift is normal, especially in houses from the 40s or earlier. Wood moves with humidity and temperature—just part of the deal. But how much movement is too much before you start worrying? If you’re not seeing fresh cracks or gaps widening, probably nothing urgent. Still, I’d keep an eye on it after big weather swings. Once had a client who ignored a tiny gap for two winters… by spring, water had gotten in and the sill was soft all the way through.
Those DIY kits can be surprisingly decent for sealing up minor cracks, but I’m always a bit skeptical about how long they’ll hold up—especially if there’s ongoing movement. Some of them get brittle after a season or two. Are you using one of those flexible sealants? The rigid stuff tends to crack again as soon as things shift.
It sounds like your slow-cure approach is working out so far, though. No leaks is always a good sign—even if you’re still keeping that towel handy just in case (I do the same with my basement window every spring; old habits die hard). Can’t blame you for being cautious.
Ever notice if your window flexes more on sunny days versus cold snaps? Sometimes direct sun can make frames expand and contract faster than you’d expect... It’s wild how much old houses “breathe.”
Those DIY kits can be surprisingly decent for sealing up minor cracks, but I’m always a bit skeptical about how long they’ll hold up—especially if there’s ongoing movement.
I get where you’re coming from, but I’ve actually had one of those flexible sealants last through three winters on my back porch window. Maybe it’s luck or maybe just less movement than I thought, but it hasn’t cracked yet. I do think prepping the surface is more important than folks realize—if there’s any dust or old paint, even the best sealant won’t stick for long. Still, I keep a close eye on it each spring... old wood loves to surprise you.
Yeah, I’m with you on the prep work making all the difference. I tried a kit on my drafty living room window last fall—spent more time scraping old paint than actually sealing. It’s still holding up, even after a couple freeze-thaw cycles. Guess I’ll see how it does next winter… old windows are always a gamble.
Old windows are a pain, no doubt. I’ve used those shrink film kits a few times and yeah, the prep is always the worst part. If you don’t get the old paint and grime off, nothing sticks right, and you end up redoing it mid-winter. Sounds like you did it right though if it’s still holding after a couple of freeze-thaws.
I’ve noticed the same thing—if you take your time with scraping and cleaning, even cheap kits can last all season. I had one window in my kitchen that was so drafty, I could feel the breeze even with the heat cranked. Did the whole kit thing last November and honestly, it made a bigger difference than I expected. Still not perfect, but at least I’m not losing all my heat out that one spot.
Only thing I’d watch for is condensation. Sometimes if the seal isn’t perfect or if there’s moisture already in the wood, you get fogging between the film and glass. Not a huge deal for me since it’s just cosmetic, but worth keeping an eye on if you’re planning to leave it up for another winter.
Old windows are always a gamble like you said. Sometimes I wonder if it’s worth just biting the bullet and replacing them, but then I see the price tag... For now, these kits are good enough for me.
Yeah, those kits are way better than I expected too. I used to think they were just a band-aid, but honestly, they’ve saved me from a few brutal drafts. I hear you on the condensation—sometimes it looks like my window’s got its own weather system. Still, beats spending thousands on replacements right now. I’ll keep patching things up until the budget says otherwise.