Trying to decide between the old-school metal flashing for my solar install, or these newer deck-mounted rubber gaskets that supposedly seal around the mounts. My roof’s asphalt shingles, about 8 years old, and I’m in a pretty rainy area (Seattle). Flashing seems tried-and-true, but the deck seals look way less intrusive and faster to install. Anyone have experience with either? Did you notice any leaks or regrets down the line?
- Helped on a job last fall where we used the deck-mounted gaskets—super quick install, but honestly, I kept wondering how they’d hold up in constant rain like Seattle gets.
- My uncle’s place has old-school flashing (asphalt shingles too), and after 10+ years, zero leaks.
- The gaskets looked clean, but I noticed some spots where the seal didn’t sit flush on uneven shingles... made me nervous.
- Haven’t seen long-term results myself, but if it was my own roof in a rainy spot, I’d probably stick with metal flashing just for peace of mind.
- Curious if anyone’s had those gaskets through a few winters without issues?
We tried those deck-mounted seals on a green roof project out here in the Northwest. The speed was great, but I noticed the same thing—any spot where the shingle surface wasn’t totally flat, the gasket just didn’t sit right. On one section, water pooled up after a hard rain, and I started worrying about seepage. Has anyone actually pulled up a panel after 3-4 years to check for rot or mold underneath? That’s my big concern, especially with all the moss and rain we get out here...
- Inspected a similar setup last fall—deck-mounted seals on a 5-year-old comp shingle roof, western exposure, lots of rain and moss.
- Pulled a few panels. Saw minor staining but no major rot or active mold. Gaskets were starting to break down where the shingles weren’t flat.
- Noticed some damp insulation below one lag bolt. Could’ve been worse if the slope was lower, honestly.
- Personally, I still lean toward traditional flashing for our climate. It’s slower but I see fewer long-term issues when I’m poking around under panels years later.
- Those deck seals are quick, but in places with heavy rain and organic debris, I’d be cautious... especially if the roof has any uneven spots.
I’ve pulled apart a few roofs in the Seattle area where folks tried those deck-mounted gaskets. They’re fine on newer, super-flat roofs, but once the shingles start to curl or you get a bit of moss, water finds its way in. I’ve seen staining and damp sheathing, sometimes even a little rot around the lag bolts after 5-6 years. Not catastrophic, but not great either.
Traditional flashing is just more forgiving with our rain. It’s slower to install, yeah, and you’ve got to lift shingles, but I rarely see leaks when it’s done right—even on older roofs. Deck seals are tempting for speed, but in this climate, I’d rather spend the extra time upfront than deal with repairs later. If your roof was brand new and dead flat, maybe I’d feel differently, but with 8-year-old shingles? Flashing still seems like the safer bet around here.
