I’ve seen a lot of those “miracle” tapes fail once the temps swing, too. Curious—did you notice any corrosion or pitting on the aluminum itself when you pulled the old flashing? Sometimes that’s what really does it in, especially if moisture’s been trapped for a while.
Curious—did you notice any corrosion or pitting on the aluminum itself when you pulled the old flashing?
Yeah, that’s usually the first thing I check. If there’s any white powdery stuff or little pits, that’s a sign moisture’s been hanging around way too long. I’ve seen “miracle” tapes just trap water underneath, especially after a freeze-thaw cycle. Sometimes the tape looks fine but the metal underneath is toast. Honestly, once the aluminum’s pitted, patch jobs are just buying time. Full redo’s the only thing that really lasts in my experience.
Title: Quick fix or redo: dealing with damaged aluminum flashing
Yeah, I’ve run into that same issue with the so-called “miracle” tapes. They look like they’re doing the job, but once you peel them back after a season or two, it’s a mess underneath. I had a spot behind my chimney where the tape actually made things worse—trapped moisture, and then the aluminum started to pit and flake. At first glance, everything looked sealed up tight, but the metal was basically crumbling underneath.
I get why people want to patch instead of replace—sometimes you just don’t have the time or budget for a full redo. But honestly, every time I’ve tried to stretch out old flashing with patches or sealants, it’s just kicked the can down the road. Especially in places that see a lot of freeze-thaw cycles (I’m in Michigan), those little pits turn into big problems fast. Water gets in, freezes, expands... next thing you know, you’ve got leaks inside.
One thing I’ll say is if the corrosion is just on the surface and hasn’t eaten through, sometimes you can clean it up and get another year or two out of it. But if you’re seeing actual holes or deep pitting, it’s not worth messing around. Full replacement is a pain but way less hassle than dealing with water damage later.
I’ve also noticed that certain spots—like valleys or anywhere debris collects—seem to go bad faster. Maybe it’s just my roof design, but those are always the first places I check now. If you’re already pulling up flashing and see white powder or rough spots, probably best to just bite the bullet and redo it right.
Not saying patches never work, but in my experience they’re more of a temporary band-aid than a real fix.
I’ve had mixed luck with patching too, especially with those tapes that promise the world. Used one on a dormer joint last fall—looked fine through the winter, but by spring, I noticed the paint bubbling on the ceiling below. Pulled up the tape and, yep, moisture had gotten trapped and the aluminum was all chalky underneath. I guess it did slow down the leak for a bit, but ended up being more work in the long run.
I get the temptation to just slap on a patch, especially when you’re staring down a busy weekend and the weather’s turning. But every time I’ve tried to stretch old flashing, it’s just come back to bite me. Maybe if you’re in a dry climate, you can get away with it, but here in upstate NY, the freeze-thaw just chews up anything less than a full replacement.
I will say, I’ve managed to squeeze an extra year out of flashing by sanding down surface corrosion and hitting it with a good sealant, but once you see holes or flaking, it’s game over. Water always finds a way.
But every time I’ve tried to stretch old flashing, it’s just come back to bite me.
That’s been my experience too. Tried patching a section over my porch with one of those “miracle” tapes—looked solid for a few months, then the first big thaw hit and water started dripping right onto my coat rack. I think the tape just hid the problem long enough for it to get worse underneath. At this point, if I see chalky aluminum or any pinholes, I just bite the bullet and replace the whole piece. It’s a pain, but chasing leaks is worse.
