the more “overkill” I went, the more convinced I was that water would find some new way in.
That’s the thing—water always finds the path of least resistance, and roofs are rarely as straightforward as those YouTube tutorials make them out to be. I’ve seen plenty of “sealed” attic fans leak after a season or two, especially if the flashing isn’t integrated under the shingles just right. Honestly, caulk is more of a last line of defense than a real fix. If you’re seeing repeat leaks, it might be worth checking if the flashing is lapped properly or if there’s an issue with the shingle layout around the fan. Sometimes it’s not about more sealant, but better integration with the roof layers.
Funny thing—every time I think I’ve outsmarted water with a “belt and suspenders” approach, it just finds a new trick. Did you use the factory flashing or try fabricating your own? Sometimes those solar fan kits don’t quite match up with certain shingle profiles, especially on steeper pitches.
- I went with the factory flashing, but honestly, I’m not convinced it’s doing much.
- My shingles are that old-school 3-tab, and the fan base didn’t sit flush, so there’s a weird gap.
- Anyone else have to wrestle with caulk and hope for the best, or is there a trick I missed?
- Starting to think water has a PhD in finding weak spots...
- Did you notice any leaks right away, or did it take a few storms to show up?
That gap under the fan base is a classic headache with 3-tab shingles. I ran into the same thing last year—factory flashing just didn’t hug the contours, and I ended up with a weird little channel for water. Tried caulk, but after a couple heavy rains, I spotted a drip in the attic. What finally worked for me was sliding a custom-cut piece of aluminum flashing under the shingles above the fan, then sealing the edges. Not perfect, but it’s held up through two storm seasons so far. Water really does have a sixth sense for weak spots...
That’s the thing with 3-tab—never quite as forgiving as architectural shingles when you’re trying to tuck in new flashing. I’ve seen caulk fail more times than I can count, especially once the sun starts baking it. I usually end up fabricating my own flashing too, but sometimes I’ll add a bead of butyl tape under the edge for a little extra insurance. Curious—did you have to lift many shingles to get your aluminum piece in, or did you just work it under the first course?
