Tackling Old Windows: My Weekend Project Went Better Than Expected

Did the same thing last spring, and it was way less intimidating than I’d built it up in my head. My house is a 70s ranch, and the old windows were basically wind tunnels in winter - could actually feel a breeze if you stood too close. I watched a bunch of YouTube videos, picked up some new vinyl replacements, and just went for it. Not gonna lie, the first one took me nearly an entire Saturday because I kept second-guessing every step. By the third window, I was moving along pretty quick, but my hands were covered in caulk and I was sore in places I didn’t even know could get sore.

What surprised me was how much quieter the house got after. Didn’t expect that. The only hiccup was one window opening wasn’t square (thanks, 70s construction), so I had to shim it like crazy and the trim’s a little… creative. Still, way cheaper than hiring someone, and I weirdly enjoyed the problem-solving part. The only thing I regret is not budgeting for new blinds at the same time - ended up with some awkward gaps until I got around to ordering those.

I do think the trickiest part is getting the measurements right. I measured like five times and still managed to make one window a hair too tight. Had to sand down the frame a bit, which was stressful but worked out. Wouldn’t say I’m ready to do it for a living, but for a DIY project, it felt like a win. Definitely more satisfying than assembling IKEA furniture, at least.

Man, I totally get what you mean about the measurements. I triple-checked mine and still had to shave a little off one side - guess old houses just do their own thing. The noise difference is wild, right? Didn’t expect my living room to feel so chill after. That caulk gets everywhere though… found some in my hair later.

Yeah, those old houses never read the manual - nothing’s ever square. I’ve learned to add a little “fudge factor” to every measurement, then just sneak up on the fit with a hand plane or sander. It’s kind of a rite of passage, right? And that caulk... I swear it multiplies when you’re not looking. One time I found a glob on my dog’s tail, no idea how that happened.

But you’re spot on about the noise. After I swapped out my draftiest window, I could actually hear the fridge humming from the next room - never realized how much street noise I’d gotten used to. Makes a huge difference, especially if you’re on a busy street.

Don’t beat yourself up over the mess. I’ve yet to finish a window job without finding caulk in my eyebrows. Comes with the territory. At least now you know the next one’ll go smoother.

That’s the truth about caulk - it ends up everywhere except where you want it. I found some on my shoe a week after finishing the last window. Getting the fit right was definitely the trickiest part for me, too. I had to trim a bit off one side because nothing in my house is square either. Next time, I’ll remember to have more shims and patience on hand. All in all, way less intimidating than I expected, but yeah - definitely earned a few new gray hairs.

I know that feeling - my last window project turned into a geometry lesson real quick. Ended up using way more shims than I thought, and still had to fudge the fit a bit. Caulk on the hands, tools, everywhere but the seam... seems like a rite of passage. If you ever find a way to keep it neat, let me know.

Funny you mention caulk everywhere but the seam - I still think I’ve got some on my watch band from last spring. I tackled a couple of drafty old double-hungs in our 1950s place, and honestly, I was convinced I’d measured right… until the frame started fighting back. Ended up using a stack of shims on one side just to get it anywhere close to square.

Here’s what worked (sort of): I taped off the edges with painter’s tape before running the bead of caulk. Then I smoothed it with a damp finger, peeled the tape right away, and wiped up any mess with baby wipes. Still got some on my jeans, though - guess that’s unavoidable.

One thing I learned: don’t rush pulling those shims out at the end. I got impatient, yanked one too early, and the whole window shifted just enough to throw off my nice caulk line. Live and learn... or just accept windows are never quite perfect in these old houses?

Live and learn... or just accept windows are never quite perfect in these old houses?

Honestly, I think you nailed it - old windows just have a mind of their own. I’ve tried to get everything square in my ‘40s bungalow and every time, something’s off by a hair. Painter’s tape is a lifesaver though. I used to skip it and ended up with caulk smeared halfway up the trim.

And pulling shims too soon? Been there. The whole thing shifted on me once after I thought I was done, so now I just leave them until everything cures, even if they look goofy for a day.

Don’t sweat the mess on your jeans - that’s basically a badge of honor. If you’re getting close to square and sealing out drafts, you’re way ahead of the game. Perfection’s overrated with these old places anyway.

Perfection’s overrated with these old places anyway.

I get where you’re coming from, but I’m not totally sold on just letting things slide. If the window isn’t square, aren’t you just asking for drafts or sticky sashes down the road? I’ve seen a lot of “good enough” installs come back to bite folks later. Sometimes it’s worth fighting for that last bit of alignment, even if it means shimming and re-checking a few extra times.

I hear you on that - nothing like a sticky sash to make you regret skipping those last few shims. I’ve worked on some real wonky frames, and yeah, it’s tempting to call it “good enough” when everything’s out of whack. But I’ve learned the hard way that a little extra patience with the level and square can save you from cold toes in January. Sometimes you just gotta wrestle it into place... even if the house fights back.

Sometimes you just gotta wrestle it into place... even if the house fights back.

That’s exactly how it felt when I tried to line up the sash weights in my front room window last month. It’s wild how something as basic as making sure things are plumb and square can turn into a full-body workout. I had this idea that a “close enough” fit would be fine, but seeing how drafty things get when there’s even a small gap really changed my mind.

I’ll admit, I underestimated how much those shims matter. I was so eager to get it done that I almost skipped a few steps, but then the window wouldn’t close right. Ended up pulling it out and re-shimming... twice. Not fun, but definitely worth it once I realized how much better it sealed.

It’s encouraging to hear someone else say patience pays off - even if it’s a pain in the moment. Makes me feel less like I’m just overthinking every step. These old houses really do have a way of keeping us on our toes.

You nailed it about shims making all the difference. I used to think they were just a formality, but after fighting with a crooked jamb for hours, I realized skipping those details just means double the work later. Funny how you start to notice every draft in an old house once you’ve fixed one window right. It’s definitely not overthinking - those little steps really do add up to a much better result. Old houses have a way of humbling you, but the payoff is worth it.

Funny how shims seem like overkill until you’re cursing at a window that just won’t sit right. I’ve tried to skip them “just this once” - never ends well. Ever tried those composite shims? They don’t split like the old cedar ones, but I swear they vanish when I need them. Old houses really do teach you patience, or maybe just stubbornness...

Isn’t it wild how something as tiny as a shim can make or break your whole afternoon? I’ve run into that too - skip a shim, and suddenly you’re fighting with the sash for hours. Composite shims are interesting. They’re definitely less fragile than cedar, but have you noticed they don’t compress quite the same way? Sometimes I miss the feel of wood, even if it splits now and then. Also, I swear they disappear into thin air the second you set them down - maybe it’s just my workbench eating them.

Old houses really do have their own rules. I’ve found myself getting way too creative with shimming in places where nothing is square. Ever tried doubling up on those plastic shims when the gap is huge? Not perfect, but sometimes it’s all you can do unless you want to rip out half the frame. I wonder if anyone’s found a “best of both worlds” shim yet...

I wonder if anyone’s found a “best of both worlds” shim yet...

I’ve wondered that too. I tried those composite shims once, but they just didn’t “give” the way cedar does. Ended up layering a wood one and a plastic one together - worked in a pinch, but probably not what the pros would recommend. Gaps in my 1920s place are all over the map, so sometimes it’s just whatever fits.

Gaps in my 1920s place are all over the map, so sometimes it’s just whatever fits.

That’s basically the story of my house too - nothing is square, and I swear every window frame is a different size by at least a quarter inch. I tried those plastic shims once, but they felt like trying to wedge in a credit card. Cedar’s got that nice bit of squish, but then you get splinters or it splits if you look at it wrong.

I’ve actually used those paint stir sticks from the hardware store when I ran out of “real” shims. Not exactly pro-level, but hey, they’re flat and cheap. I’ve also stacked random bits of wood and plastic together like you did - kinda like shimming Jenga. It holds for now, but if a contractor ever opens up these frames, they’ll probably just shake their head and laugh.

Honestly, with these old houses, sometimes you just have to embrace the chaos and use whatever gets the job done.

That’s the spirit - sometimes “good enough” is exactly what these old places need. I’ve done the paint stick trick too and honestly, it works just as well as anything else most of the time. Have you ever tried those composite shims? I was skeptical, but they didn’t split like cedar. Still, nothing beats grabbing whatever scrap is lying around when you’re in the middle of a job and can’t make another trip to the store.

I actually tried composite shims for the first time last month when I was rehanging a door. They definitely hold up better than the cedar ones - no splitting, even when I got a little heavy-handed with the hammer. Only thing is, they’re a bit too flexible sometimes? Like, I had to stack a couple to get the right thickness, and it felt a little less solid than wood. Still beats driving back to the store for one missing shim, though. Funny how those random scraps end up being the MVPs mid-project...

I get what you’re saying about composite shims not splitting - I’ve had cedar ones snap on me more times than I can count, especially when I’m in a rush. But honestly, I still lean toward wood for anything that actually matters structurally. The flex in the composite ones just bugs me, especially if you’re dealing with old window frames that aren’t exactly square to begin with. Stacking them can get a little weird, and sometimes it feels like you’re just wedging in a piece of rubber that’ll shift over time.

I know it’s tempting to use whatever’s on hand (I’ve jammed paint stirrers and even bits of old flooring under things in a pinch), but for rehanging doors or leveling window sills, I trust wood more. At least if it compresses, it sort of “locks in” over time instead of bouncing back. Maybe I’m just set in my ways… but every time I try something new like composite, I end up second-guessing myself halfway through the job.

Curious if anyone’s actually had those flexible shims hold up long-term? Or do they eventually wiggle loose?

I’m right there with you - wood shims just “bite” into place in a way composites never seem to. I’ve used the plastic ones on a couple of jobs (mostly when I ran out of cedar), and they’re fine for quick fixes, but over time I’ve noticed they can shift, especially if the frame’s a little out of whack. One thing I do sometimes is use a wood shim for the main support and then a composite one behind it to fine-tune the angle. Not perfect, but it helps if you’re short on materials. For anything that’s got some weight or movement, though, I always go back to wood.