I’ve been through the same headache with a solar attic fan install, and honestly, I wish I’d known about the polyurethane sealant option before I started. My house is about 30 miles south of Dallas, asphalt shingles, pretty standard pitch. When I first put in the fan, I used roofing cement because that’s what my dad always swore by. Looked great for the first year or so, but after our first real summer—triple digits for weeks—the stuff started cracking around the flashing. Didn’t even notice until a big storm rolled through and water found its way into my attic insulation.
Had to pull up a couple shingles and redo the whole area with a polyurethane caulk (think it was NP1 or something similar). No leaks since then, and it still looks flexible even after another brutal summer. Roofing cement’s fine in a pinch, but in Texas heat, I’m convinced it’s just not up to the job long term. If you’re already up there doing the work, might as well use something that’ll last through more than one season of sun and hail.
Man, I feel this. Tried to cheap out with the black goo (roofing cement) on my shed roof last summer—figured, hey, it’s only a shed, right? By August, it was peeling up like old duct tape. Ended up spending more fixing it than if I’d just used the good stuff to start. Polyurethane caulk isn’t cheap, but neither is replacing soggy insulation... lesson learned.
That’s wild—didn’t realize how fast the cheap stuff can fail. I’ve always wondered, is there ever a situation where roofing cement actually holds up long-term, or is it just a band-aid no matter what? I’ve seen some old-timers swear by it for flashing, but then again, they’re usually patching things every couple years anyway.
With the solar attic fan install, I was debating whether to use the pricier caulk or just slap on some black goo since it’s technically “temporary” until I redo the whole roof. But after reading this, maybe it’s just not worth the risk, especially with how much water can sneak in around those vent flanges. Did you notice any leaks right away, or did it just start peeling and then the water got in?
Also, is polyurethane caulk easy to work with? I’m still getting the hang of applying sealants without making a mess. It’s crazy how much difference the right (or wrong) product makes, even on something as “simple” as a shed.
Roofing cement is like duct tape for your roof—handy in a pinch, but you’re gonna regret it if you expect miracles. I tried it once on a vent flashing and it lasted maybe a year before it started cracking. Poly caulk’s a bit stickier to work with, but it actually seals and flexes with the roof. I’d say it’s worth the extra bucks, even for a “temporary” fix. And yeah, water finds every little gap... learned that the hard way after a surprise drip right over my workbench.
Yeah, I’ve been down that road with roofing cement too. It’s tempting when you just want to get the job done, but it never seems to last through a full season here. I switched to a low-VOC sealant last time—messier, but no leaks so far. Funny how the “quick fixes” always end up being more work in the long run.
