That’s interesting about the breathable synthetic—funny how skeptical I was too, but it actually did make a difference with condensation in my attic last year. I hear you on the slickness, though. Nearly slid off the thing more than once, and I’m not even on a steep pitch.
Full self-adhered membrane is a whole different animal. I bit the bullet after a nasty windstorm ripped up half my old felt underlayment. Expensive, yeah, but I slept better during storms after that. Still, unless you’re in a spot with crazy freeze/thaw cycles or you’ve had ice dam nightmares, it does feel like overkill for most roofs. Around here (mid-Atlantic), I stick with synthetics and just pay extra attention to flashing and ventilation.
Honestly, there’s no perfect answer—just trade-offs. But it’s good to hear the breathable stuff is working out for you. Always feels like a gamble trying new products, but sometimes they surprise you.
- Totally get what you mean about the “slickness” of synthetics. I was up there with my brother-in-law and we both looked like we were auditioning for a slapstick comedy. Not sure if it’s just the brand I picked or if they’re all like that, but it definitely made me rethink my footwear choices.
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“Full self-adhered membrane is a whole different animal. I bit the bullet after a nasty windstorm ripped up half my old felt underlayment.”
That’s exactly what I’m worried about. My neighbor had his felt peel up after a storm last fall and it was a mess—water stains everywhere, insurance headaches, the works. I’m in central PA, so we get those surprise wind gusts too, but not as much ice dam stuff (thankfully).
- I went with a synthetic underlayment this spring when I replaced my roof (asphalt shingles, nothing fancy). The roofer talked me out of full peel-and-stick everywhere—said it’s great for eaves and valleys but probably overkill for the whole thing unless you’re in the deep freeze zone. Saved me some cash, which was nice since I already blew my budget on gutters.
- Ventilation seems to be the big thing everyone keeps hammering home. My attic used to feel like a sauna in July and an icebox in January. After fixing some blocked soffit vents and adding a ridge vent, things are way more stable. Not sure if it’s the underlayment or just better airflow, but no more condensation drips so far.
- If underlayments could talk, mine would probably just complain about my amateur hammer skills and all the extra nails I put in “just to be safe.” But hey, at least it’s staying put.
- Still crossing my fingers that trying something new doesn’t come back to bite me in five years... but for now, dry ceilings and no leaks feels like a win.
- Price was my main decider—synthetic seemed like a good middle ground. I was tempted by the full peel-and-stick, but the cost made me wince, and my roofer said it’s really only needed in the “problem” spots.
- I’ll admit, walking on synthetic felt like stepping onto a skating rink after a rain. Nearly lost my balance more than once.
- Not sure any underlayment is perfect, but I’d rather patch a leak than pay double up front.
- My attic’s finally not a sweatbox, so maybe that’s the real win... or maybe I just got lucky with the weather this year.
- If mine lasts 10+ years, I’ll call it a success—even if it grumbles about my DIY skills.
I’ll admit, walking on synthetic felt like stepping onto a skating rink after a rain. Nearly lost my balance more than once.
Yeah, that’s no joke—synthetic’s slick when it’s wet. I’ve nearly eaten it a few times myself. I went with peel-and-stick just in the valleys and around chimneys, rest is synthetic. Figured it was a decent compromise. Haven’t had leaks yet, but I’m not holding my breath for 20 years either. Ten sounds about right if the weather doesn’t get wild.
Peel-and-stick in the valleys and around chimneys is a solid move—those spots always seem to be the first to go when storms roll through. I’ve seen synthetic hold up decently, but you’re right, 20 years is a stretch unless you’re in a super mild climate. Around here (Midwest), hail and wind will test any underlayment way before then. One thing I’ve noticed: if the synthetic isn’t nailed down just right, it can bunch up or even tear under heavy foot traffic or debris. Not a dealbreaker, but worth watching for.