- Ran into this exact issue last winter—thought a bead of caulk would hold me over, but after a couple heavy freezes, stains started showing up on the bedroom ceiling.
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That was definitely true in my case. By the time I noticed, the plywood underneath was already soft.“If you’re already seeing stains inside, it’s usually too late for another patch.”
- Ended up pulling a few shingles and swapping out the flashing. Not as intimidating as I’d expected, just took some patience.
- Agree on the metal compatibility thing. I almost grabbed copper by mistake... glad I double-checked since I’ve got aluminum everywhere else.
- Lesson learned: patching is fine in a pinch, but if you can see water damage inside, it’s probably worth doing the full fix.
Had a customer in a similar spot last fall—aluminum flashing around a chimney, mid-90s roof, and they’d been patching every year with sealant. Looked fine at first glance, but once the ceiling stains started, it was already too late for another band-aid job. I get why people want to try a quick fix; sometimes you just hope you can stretch it to spring or avoid pulling up shingles. But water’s sneaky... once it finds a path, it’ll keep coming back.
Pulling the shingles and swapping out the flashing isn’t as bad as it sounds, like you said. Most of the time, the hardest part is just getting up there and not damaging surrounding shingles. I’ve seen folks mix metals by accident, too—galvanic corrosion can sneak up on you if you don’t pay attention. Aluminum touching copper or even some fasteners, especially in wet climates, just accelerates the problem. One job I remember, they’d patched with copper sheet and aluminum nails... by year two, the fasteners were basically gone.
I’m all for patching in an emergency, but if you’re seeing stains inside, odds are the underlayment and decking have already taken a hit. Once plywood gets soft, there’s really no shortcut—rip out the damaged section, make sure it’s dry, then replace the flashing and shingles. Not the cheapest way out, but cheaper than letting it spread and having to replace a whole section of roof.
Funny thing is, most people think flashing lasts as long as the shingles, but in my experience, it’s usually the first thing to go, especially around chimneys and valleys. I always suggest folks check those spots every year instead of just looking for missing shingles. A little prevention goes a long way, especially if you’re in an area with freeze-thaw cycles.
Anyway... caulk’s fine for a quick patch, but once water’s made it inside, it’s time for the bigger fix. Learned that lesson a few times myself.
That’s spot on about flashing usually being the first thing to fail. I used to think shingles were the weak link, but after pulling up a few old roofs, it’s almost always the flashing that’s rusted out or pulled away. Had a job last winter where the homeowner kept slapping on more caulk every year—by the time we got in there, the plywood was like a sponge. I get wanting to avoid a big repair, but once you see stains inside, it’s pretty much game over for patching. Mixing metals is another one people don’t realize can cause so much trouble... I’ve seen aluminum flashing with steel nails just dissolve in a couple seasons, especially with all the rain we get here. Prevention’s way less hassle than tearing out rotten decking, that’s for sure.
- Been there with the caulk “fixes”—I swear, half my garage is tubes of the stuff from trying to stretch old flashing a few more seasons. Never really works for long, just slows the inevitable.
- I used to think I could just patch over stains inside, but once you see those brown rings on the ceiling, it’s usually too late for a quick fix. Had to replace a whole section of decking last year because I waited too long.
- Mixing metals is sneaky. Did it once by accident—aluminum flashing, steel nails. Looked fine for a year, then suddenly everything was corroded and leaking. Now I double-check every fastener before I start.
- If you’re in a wet climate like me (Pacific NW), flashing is basically the first thing to rot out. I try to check it every spring and fall, but sometimes life gets in the way...
- My two cents: if you’re seeing stains or soft spots, bite the bullet and redo the flashing. It’s a pain now but way less hassle than dealing with soggy plywood or mold later.
- Quick fixes are tempting, but they always come back to haunt me. Learned that one the hard way—twice.
- Seen a lot of those “caulk fixes” out in the wild. Like you said, it just buys time. Eventually, water finds a way.
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Mixing metals is sneaky. Did it once by accident—aluminum flashing, steel nails. Looked fine for a year, then suddenly everything was corroded and leaking.
That’s a classic one. Galvanic corrosion can sneak up on you fast, especially in damp climates.
- Quick fixes sometimes mask bigger problems underneath—soft decking or hidden rot. I’ve seen folks patch over stains for years, only to discover mold spreading inside the attic.
- If you’re already seeing stains or warping near flashing, redoing it is usually the smarter move. It’s more upfront work but saves a ton of hassle (and cash) down the line.
- One thing I always check: are gutters dumping water right onto flashing? Sometimes it’s not just the flashing itself but bad runoff patterns making things worse.
