Can’t argue with you on the humidity—down here in Florida, felt just doesn’t stand a chance. First time I helped lay it, we had a pop-up shower and the stuff looked like a crumpled paper bag by the next morning. Tried cap nails and even doubled up the edges, but the wind still found a way to get under there.
I’ll admit, synthetic’s not my favorite to walk on, especially on a 10/12 pitch... but I’d rather take it slow with a harness than have to chase felt halfway down the street after a storm. The textured ones are definitely less sketchy, but I still move like a grandma up there.
Price was a shock at first, but after having to redo a section of felt twice in one week (thanks, summer storms), I get why folks say synthetic pays for itself. Only thing I miss about felt is how easy it is to cut—synthetic can be stubborn if your knife’s dull.
All in all, I’m with you: soggy underlayment is just asking for trouble. If it’s gonna rain sideways every other afternoon, might as well go with what holds up.
- Had a similar experience last hurricane season—felt just turned to mush after two days of rain, even with extra fasteners.
- Switched to a recycled synthetic (trying to keep it green where I can). Not the easiest to cut, but it held tight through some nasty wind gusts.
- Agree on the price—stings at first, but not having to redo sections is worth it.
- Only real gripe: gets slick when there’s morning dew, so I’m extra careful on steeper slopes.
- Still, I’d rather deal with that than peeling up soggy felt every time the weather turns.
- Seen the same thing with felt—once it’s soaked, it’s basically useless, especially in humid climates.
- Synthetics are a big step up for wind and water resistance. I’ve noticed they don’t wrinkle or tear as easily when installers walk on them, which helps with shingle alignment later.
- Price is higher, but if you factor in labor for repairs, it balances out over time.
- The slickness is real—almost wiped out on a 7/12 pitch last fall. Some brands have a bit more grip, but none are perfect.
- Only downside I’ve run into: some synthetics can trap moisture if the decking isn’t vented well. Worth double-checking attic airflow before switching over.
Can definitely relate to the felt issues—down here in the Gulf, once it’s wet, it’s game over. I’ve switched almost entirely to synthetics for re-roofs, mostly because of the durability and how they handle foot traffic. You’re spot on about the wrinkle factor. With felt, I’d see it bunch up under shingles, especially if we had a rain delay, and then you’re fighting alignment the whole way up.
The slickness is no joke, though. Had a guy on my crew take a pretty good slide last summer—luckily, he was roped in, but it rattled him. I’ve noticed some brands (like Deck-Armor) seem to have a bit more grip, but it’s still not something I’d trust on a steep pitch without fall protection. Curious if anyone’s found a synthetic that’s noticeably less slippery? I’ve tried a few, but haven’t found one that really solves it.
On the moisture side, I’ve run into that with older homes where attic venting isn’t up to code. Synthetics just don’t breathe like felt, so if there’s any kind of condensation issue, it’ll show up quick. Had a job last year where the decking started to cup because moisture got trapped—ended up having to add more soffit vents and a ridge vent after the fact. Not ideal, but lesson learned.
Has anyone tried those “breathable” synthetic underlayments? I’ve seen them advertised but haven’t heard much from folks actually using them in the field. Wondering if they’re worth the extra cost or just marketing hype.
I’ve been wondering about those “breathable” synthetics too. I’m in an older house with a low-slope roof, and after a bad rain last year, we had some moisture show up in the attic—nothing major, but enough to make me nervous. I keep hearing that the new synthetics are supposed to be better, but I can’t tell if it’s just clever marketing or if they actually help with trapped moisture. Has anyone noticed a real difference in how their attic feels or smells after switching? I’m trying to figure out if it’s worth paying extra or if I should just stick with what’s worked so far...
