finally found an underlayment that lasts - what's your experience?

I’ve wondered the same thing about the “grippy” synthetics. Last fall I helped my brother redo his roof - steep pitch, old farmhouse style - and he insisted on using one of those newer synthetic underlayments with the textured surface. I was skeptical, honestly. I’ve always used felt too, just because it’s cheap and familiar.

But I’ll say this: we had a couple of misty mornings where the roof was damp, and it really did feel a lot less slippery than felt. Not like walking on sandpaper or anything, but noticeably better grip underfoot. Still, when it started raining for real, we got down fast - didn’t trust anything at that point.

Only downside I noticed is that some of those synthetics can be a pain to cut straight, especially if there’s wind. But for working on a steep roof, I’d pick the grippy stuff over regular felt now. Maybe not a miracle, but definitely not just marketing hype in my experience.

- Noticed the same thing with synthetics on inspections lately - grip is a big plus, especially on anything steeper than 6/12.
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“we had a couple of misty mornings where the roof was damp, and it really did feel a lot less slippery than felt.”

That lines up with what I’ve seen. Felt turns into a slip-n-slide even with a little dew.
- Durability-wise, synthetics hold up better if the shingles aren’t going on right away. I’ve seen felt wrinkle and tear after a week of sun or a windy day - synthetic usually stays put.
- Agree about cutting issues. Wind can make it a mess, and some brands curl up at the edges if you don’t tack them down fast.
- Only real downside I’ve run into: a few older houses with rough decking (splinters, nail heads sticking up) can snag or puncture the synthetic, especially the thinner rolls. Worth checking the deck before rolling it out.
- For longevity, synthetics are winning out in my area (Midwest, lots of freeze/thaw). Haven’t seen one fail early yet, while old felt sometimes starts to break down under leaks.
- Still, nothing’s totally slip-proof in the rain - good call getting off the roof when it started coming down. Safety first.

- Seen the same with synthetics - way better grip, especially on those steeper pitches where you really don’t want to be skating around.
- Biggest headache for me is when the wind picks up mid-roll... had a whole sheet take off like a kite once.
- I still keep some felt on hand for patch jobs or weird spots, but for anything big, synthetics just last longer and don’t wrinkle up like wet newspaper.
- Agree on the rough decking - just had a job where old nail heads poked right through the underlayment. Had to go back and fix it before shingles went on.
- Midwest winters here too, and so far no early fails with synthetic. Just wish they’d figure out how to make it lay flat every time - some days it feels like wrestling an octopus.

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Just wish they’d figure out how to make it lay flat every time - some days it feels like wrestling an octopus.

Yep, totally get this. My first time watching the crew put down synthetic, I thought it was supposed to just roll out smooth... not curl up like a party streamer.
- Midwest here too - our wind is no joke. Saw a neighbor’s underlayment halfway across the yard last fall.
- Still confused if I should bother with felt for the little spots, or just stick with synthetic everywhere?
- Not loving how slippery it gets with frost in the mornings, but at least it doesn’t soak up water like felt.
- Anyone else notice static shocks when handling synthetic, or is that just me being unlucky?

Static shocks - yeah, that’s not just you. Happened to me a bunch last fall, especially when it was dry out. I’ve only used synthetic for the last two roofs and honestly, I wouldn’t go back to felt except maybe for tiny patches or weird corners. The wind here (central Illinois) is brutal too. Had to chase a roll down the street once... not fun. Slippery mornings are rough, but at least it dries quick after rain.