Curious if anyone’s had issues with synthetics getting brittle after a few years? That’s been my only reservation.
I’ve seen that too, especially on properties where the attic gets super hot—synthetic can get kind of crispy over time. Here’s what I usually look for: 1) check the manufacturer’s temp ratings, 2) see how much direct sun exposure it’ll get before shingles go on, and 3) ask around about local installs. Has anyone noticed if certain brands hold up better in high heat? I’m still not convinced synthetics are always the answer, especially for older buildings with poor ventilation.
I kind of get what you’re saying about synthetics getting brittle. When we bought our place (built in the late 70s), the inspector pointed out that the old felt underlayment was still holding up okay under the shingles—just a few spots where it had worn thin. We’re in central Texas, so summers are brutal. I went with synthetic for a patch job last year because everyone said it was “the new standard,” but now I’m second-guessing it after reading stuff like:
synthetic can get kind of crispy over time
I crawled up there last month and noticed the exposed edge already felt stiffer than I expected, and it’s only been a year. Maybe it’s just the brand, but I’m starting to think felt might actually be better for older houses like ours, especially since our attic ventilation isn’t great. Not sure if anyone else has seen this, but I’m definitely watching for any signs of cracking or curling at the seams. Sometimes “newer” doesn’t mean better, I guess...
I crawled up there last month and noticed the exposed edge already felt stiffer than I expected, and it’s only been a year.
Yeah, I’ve noticed that too with the synthetic stuff. We did a small repair on our shed roof last spring using synthetic because it was lighter and easier to handle, but after one Texas summer, it’s already looking kind of warped at the edges. The old felt on our main roof is still hanging in there, even though it’s probably 15+ years old. Maybe felt just handles the heat better, especially if your attic isn’t vented well. I’d keep an eye on those seams, for sure. Sometimes “new standard” just means “cheaper to ship,” not necessarily better for every house.
Here’s what I’ve seen over the years, especially after big storms: synthetic underlayment is lighter and easier to roll out, but it just doesn’t seem to take heat and UV like old-school felt. You get a few months of direct sun—especially somewhere hot like Texas—and those edges start curling or stiffening up. I’ve even seen some synthetics get brittle and crack if they’re left exposed too long before the shingles go on.
Felt’s heavier, yeah, but it seems to “settle in” better and doesn’t mind a little moisture or heat. If there’s a leak or a shingle blows off, felt usually holds up long enough for you to fix it before water gets inside. With synthetic, I’ve seen water sneak under the seams if they start to lift.
If you’re in a spot with wild temperature swings or lots of sun, I’d lean toward felt unless you need something super lightweight for a tricky install. Either way, check those seams every season—especially after storms. A little maintenance now beats a full tear-off later... trust me.
You nailed it—felt just seems to hang in there when the weather gets wild. I’ve had synthetic peel up on me after a couple months of Texas sun, but the old felt just shrugs it off. Maintenance is a pain, but you’re right... beats a waterfall in the living room.
