- Seen a lot of “easy” installs get wrecked by skipping the little things—flashing is always where folks cut corners, and it bites them after the first real storm.
- Had a job last fall where a homeowner used some bargain-bin gasket—thing was toast after one winter. Ended up with water stains and a nasty bit of mold in the attic. Polyurethane sealant’s saved me too many times to count, especially up here in the Midwest where freeze-thaw is brutal.
- Energy savings are tricky. I’ve seen attic fans drop temps by 10-15 degrees, but if the insulation’s not up to snuff, that cool air just leaks right out. Sometimes people expect their electric bill to get slashed in half, but honestly, unless you’re sealing everything else up, it’s minor.
- One thing I’d add—if your roof’s older or you’ve got a low slope, those fans can actually make leaks worse if the flashing isn’t perfect. Not everyone thinks about that.
- End of the day, it’s all about the details. The fan is the easy part... keeping water out is where you earn your keep.
Had a similar situation last summer—thought I could just pop the fan in and call it a day. Ended up chasing a slow leak for weeks because I didn’t get the flashing tucked right under the shingles. Midwest storms found every gap. Lesson learned... take your time with the details, even if it feels like overkill.
Ended up chasing a slow leak for weeks because I didn’t get the flashing tucked right under the shingles.
That’s exactly what happened to me, except it was a green roof install. Did you notice any issues with ice damming after? I found that even a tiny misalignment with the flashing led to water pooling under the sedum trays. Makes me wonder—do you think traditional asphalt shingles are more forgiving than green roof membranes when it comes to these kinds of penetrations?
I ran into something similar when I put in my solar attic fan last fall. My roof’s just regular asphalt shingles, nothing fancy, but even then, getting the flashing to sit right was a pain. I thought I had it nailed (literally and figuratively), but a couple weeks later, I noticed a little drip in the attic after a heavy rain. Turns out, one shingle was just barely lifted and water found its way in. Had to pull up a few rows and redo it—definitely not as “easy” as the YouTube videos make it look.
I’ve never done a green roof myself, but I can see how those would be way less forgiving. With shingles, you’ve got a bit of wiggle room—if you mess up, you can usually lift and reseat them without too much trouble. Plus, the overlap helps hide small mistakes. But with those membrane systems under sedum trays? Seems like even a tiny gap or wrinkle could cause pooling or leaks, especially if water gets trapped under the trays and can’t dry out. I’d be nervous about that, especially in winter.
Ice damming hasn’t been a huge issue for me, but I’m in a milder climate (Pacific Northwest), so we don’t get the deep freezes some folks do. Still, I always worry about any spot where water might sneak in and freeze. Even with shingles, if the flashing isn’t perfect, you’re asking for trouble once things start thawing and refreezing.
Honestly, I went with asphalt because it’s cheaper and easier to patch up if something goes wrong. Green roofs look awesome, but I’d be worried about long-term maintenance and hidden leaks. Maybe I’m just too cautious (or cheap), but I like being able to fix stuff myself without tearing up half the roof.
Curious if anyone’s tried those peel-and-stick flashing tapes under shingles? I used some around my vent pipe and it seemed to help, but not sure how it’d hold up under a green roof setup.
I hear you on the YouTube “easy install” thing—every time I try to follow along, there’s always some step they gloss over that ends up being a huge pain. I did my first attic vent last summer and had a similar issue with the flashing not sitting flush. Ended up with a small leak that took me forever to track down. I’m honestly a bit paranoid now about anything that messes with the roofline.
About those peel-and-stick tapes, I used one (Grace Vycor, I think?) around my skylight curb when I patched it last year. It seemed to work fine under shingles, but I have no idea how it’d hold up under a full green roof—seems like the constant moisture and weight would be a whole different ballgame. Anyone actually seen how those tapes do long-term if they’re buried under soil or trays? Or do they just break down after a couple seasons?
I’m in the Midwest, so we get freeze/thaw cycles and ice dams are always in the back of my mind. Sometimes I wonder if all these “upgrades” just make things more complicated than they need to be...
