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

Synthetics are a mixed bag in my book. The UV claims always sound good until you actually test them in real life.

I get where you’re coming from, but I’ve actually had the opposite experience with some of the newer synthetics - specifically the heavier ones. I left a roll of Deck-Armor on a job for almost two months last fall (thanks to supply delays and a couple nasty storms), and it held up better than any felt I’ve ever used. No curling, no brittleness, even after some pretty strong sun on a west-facing slope. Maybe it’s brand-specific, or maybe we just got lucky with the weather that time.

I do agree about not trusting those “90-day” claims blindly, though. Some of the lighter synthetics are basically plastic wrap and don’t stand a chance if you get more than a week of direct sun or a big windstorm. Tarping overnight is smart, but I’ll admit I don’t always have the patience for it unless there’s rain in the forecast.

Guess it comes down to picking your battles - and your materials - based on what you’re up against that week. Midwest weather keeps us humble, that’s for sure.

I’ve had my share of trial and error with underlayments over the years. Back in 2017, I went with a lighter synthetic on my garage roof, thinking it’d be fine for the few days before the shingles went on. Well, two days of July sun and a windstorm later, that stuff was flapping like a cheap tarp. Ended up redoing half of it before the inspector even showed up. Lesson learned: not all synthetics are created equal.

I’m with you about the heavier rolls holding up better. Last spring, I used Titanium UDL30 on a re-roof (about 26 squares, 6/12 pitch) and left it exposed for nearly three weeks waiting on materials. No curling, no leaks - even after a couple classic Midwest thunderstorms rolled through. The difference in thickness is pretty obvious when you unroll it; feels closer to an actual membrane than some of the thinner options.

But yeah, I still don’t trust those “90-day UV exposure” stickers either. Maybe in theory they work, but real-world weather has a way of finding the weak spots. And honestly, once you see one section start to degrade or get brittle, it’s hard not to second-guess all your prep work.

One thing I’ve noticed - some of these synthetics are slick as ice when there’s morning dew or frost. Had a buddy slip right off a low slope because he wasn’t paying attention (he was fine, just bruised his ego). I started keeping a pair of those grippy roofing shoes handy after that.

I guess at the end of the day, I’d rather pay a little more for something that buys me time if there’s a delay or surprise storm. Midwest weather is unpredictable enough without having to redo underlayment every time Mother Nature throws a curveball...

But yeah, I still don’t trust those “90-day UV exposure” stickers either. Maybe in theory they work, but real-world weather has a way of finding the weak spots.

Couldn’t agree more. Those stickers are marketing, not magic. I’ve yet to see any underlayment actually look decent after even half that time in direct sun and wind, especially with Midwest humidity. I’ve had luck with UDL30 too, but I still hustle to get shingles on as soon as possible. One rogue storm and you’re redoing seams or chasing leaks... not worth the gamble. And yeah, the slip factor is real - almost ended up on my butt more than once when there’s dew. Grippy shoes are a must.

UDL30’s been solid for me too, but yeah, I never trust those exposure ratings. Had a buddy try to push the 90 days - ended up with warped seams after a week of storms. I’m always double-checking for wrinkles or tears before shingling. Those early morning slips are no joke either... learned quick to ditch old sneakers for something with grip.

UDL30’s been decent for me, but yeah, I don’t trust those “90 day” claims either. I left a roll exposed for maybe two weeks last fall - one windy storm and it looked like a crumpled chip bag. And man, slipping off the roof in old running shoes... never again. Those grippy boots are worth every penny.

I’ve had similar issues with UDL30 - on paper, it sounds tough, but in practice, a couple weeks of Midwest wind and rain and it starts to look rough. I’m not convinced by the “90 day” exposure rating either. I left a section uncovered for about ten days last spring and it started curling at the edges. Maybe it’s fine if you get perfect weather, but that’s rare around here.

On the footwear - totally agree. I tried to save money using old sneakers and nearly slid right off a 6/12 pitch. Switched to Cougar Paws after that, and honestly, they made a huge difference. Not cheap, but way better grip.

If you’re looking for something that actually holds up, I had better luck with Titanium UDL50. It’s pricier, but after a month exposed (and a couple storms), it was still flat and tight. Not saying it’s perfect, but definitely less hassle than the cheaper stuff. Just my two cents...

UDL30’s “90 day” thing always felt like wishful thinking to me. I remember the first time I used it, the forecast looked clear for a week, so I figured I’d be fine. Of course, two days in, we got one of those sideways spring storms and by the end of the week, the stuff was flapping around like a cheap tarp. Had to go back up there and re-tack half of it - definitely not what you want when you’re trying to keep things moving.

I’ve tried UDL50 too, and yeah, it’s definitely tougher. The price hurts a bit, but after dealing with the cheaper stuff peeling up or curling every time the wind picks up, I’ll pay extra just to avoid that headache. Only thing is, even UDL50 gets slick if there’s frost or heavy dew in the morning. Nearly did the splits once stepping onto a patch before sunrise - made me rethink my whole approach to early starts.

On shoes, you’re spot on. I used to think any old pair would do until I ended up sliding down a 7/12 with nothing but my pride (and some bruises) left at the bottom. Now I don’t mess around - Cougar Paws or nothing. They’re not magic, but they’re way better than sneakers.

One thing I’ve noticed: no matter what underlayment you use, if your roof’s got weird angles or valleys that catch water, nothing holds up forever if it sits exposed too long. Midwest weather just chews through everything eventually. At this point, I just build in extra time for covering up fast and hope for decent weather... which almost never happens.

Anyway, glad someone else has had better luck with UDL50 - it’s not perfect but at least it doesn’t turn into a potato chip after a week of rain and wind.

UDL30’s “90 day” claim always felt like a marketing fairy tale to me too. I put it down on my shed roof last fall, thinking I’d have plenty of time before the shingles went on. Two weeks later, we got one of those classic Midwest windstorms - felt like the whole thing was trying to take flight. I spent a Saturday chasing flapping corners and cursing myself for trusting the label instead of my gut. Never again.

UDL50 is definitely a step up, but man, you’re right about the price tag. I grumbled at checkout, but after seeing how it held up through a couple of those sideways rains (the kind where you wonder if your house is about to float away), I stopped complaining. Still, nothing’s perfect - last winter I nearly did a cartoon-style wipeout on some frosty UDL50 at 6am. My neighbor saw the whole thing and still brings it up every time he sees me with a ladder.

Shoes are another one where I learned the hard way. Tried to save money with some old hiking boots once... ended up sliding down my porch roof and landing in the bushes. Now it’s Cougar Paws or bust for anything steeper than a garden shed.

I will say, even with the “good stuff,” if you’ve got weird dormers or valleys that collect water, you’re just buying yourself time - not invincibility. Had a spot over my kitchen that started bubbling after three weeks exposed, and that was with UDL50 plus tarps. Midwest weather doesn’t care what you paid for underlayment - it’ll chew through anything if you give it long enough.

If there’s one thing I’ve learned, it’s to never trust the forecast and always have extra tarps handy. And maybe invest in better shoes before you end up as neighborhood entertainment...

UDL30’s “90 days” is wishful thinking in my book, too. I had a job last spring where we got hit with a surprise thunderstorm after just a week - half the underlayment peeled up like a banana. Since then, I always double up on fasteners and keep a roll of ice & water shield handy for tricky spots, especially valleys and low slopes. Pricey stuff like UDL50 does hold up better, but you’re right, nothing’s bulletproof if the weather turns nasty. And yeah, Cougar Paws are worth every penny - my knees and pride are both grateful.

UDL30’s “90 days” always felt like a marketing stretch to me, too. I’ve seen it go south in half that time when the weather turns ugly - especially if you get those pop-up summer storms. I remember one job where we had a bluebird forecast, then out of nowhere, sideways rain and wind gusts. The underlayment was flapping before we could even tarp it down. Since then, I’m with you - double up on fasteners, and I don’t skimp on the ice & water shield for valleys or anywhere water might sneak in.

I’ve tried UDL50 and even some of the titanium stuff. It’s definitely tougher, but nothing’s invincible if Mother Nature decides to throw a tantrum. Around here (coastal Carolina), humidity and salt air chew up everything faster anyway. I’ve also noticed that how you install matters just as much as what you use - if there’s any slack or it’s not tight around penetrations, it’ll find a way to fail.

Funny you mention Cougar Paws - I used to think they were just another gimmick until my old boots slipped out from under me on a 10/12 pitch. Never looked back after that... knees are still mad at me for waiting so long.

One thing I started doing is keeping a couple rolls of peel-and-stick in the truck for emergency patches. It’s saved my bacon more than once when the weather turned mid-job. Costs more upfront, but beats coming back to fix water damage later.

Curious if anyone’s had luck with those newer self-healing underlayments? I’ve heard mixed things, but haven’t tried them yet myself. Always looking for something that can stand up to our crazy storms without costing an arm and a leg.

That’s interesting about the self-healing underlayments - I’ve been eyeing them too but haven’t pulled the trigger. I keep wondering if they actually “heal” after a nail or staple, or if that’s just marketing talk. Also, has anyone tried any of the recycled-content or “eco” underlayments? I’m always looking for something that’s a little less harsh on the environment, but I don’t want to sacrifice durability, especially with the wild weather swings we get here.

I keep wondering if they actually “heal” after a nail or staple, or if that’s just marketing talk.

Tried one of those “self-healing” underlayments last year after a hailstorm did a number on my shed. Honestly, it does close up around nails better than the old felt stuff, but “heal” is a strong word - think more like a band-aid than Wolverine. As for the eco ones, I put a recycled-content roll on my garage roof. Held up fine through heat and snow, but it did get a bit wavy in the humidity. Not a dealbreaker, just something to watch for if your weather’s as wild as ours.

That “self-healing” label always seemed a bit optimistic to me. I’ve pulled up shingles after a season and yeah, the synthetic underlayment does kind of seal around the nail holes, but it’s not like the hole disappears. It just doesn’t gape open like felt does. I’ve noticed some brands handle expansion and contraction better than others - humidity here in the Midwest can really mess with cheaper rolls. Haven’t tried the recycled stuff yet, but if it gets wavy, I’d worry about shingle laydown over time.

That’s a good point about the “self-healing” thing. I remember the first time I heard that, I pictured the hole just closing up like magic, but in reality it’s more like the material just hugs the nail a bit tighter. Still, way better than felt, which always seemed to tear or stay open around fasteners, especially after a hot summer.

Humidity’s a pain here too (I’m in southern Illinois), and I’ve seen some of those budget synthetics wrinkle up or get all bunched under the shingles. Makes for a lumpy finish and can mess with how the shingles lay down. One of my old bosses used to say, “If it looks wavy before shingles, it’ll look worse after.” Not sure if that’s always true, but it stuck with me.

Haven’t tried recycled underlayment either - kinda curious but also nervous about durability. If you ever do give it a shot, I’d be interested to hear how it holds up. For now, I just stick with brands that have a bit more weight to them. Seems to help with expansion and contraction, at least in my experience.

- Totally agree on the “self-healing” thing - first time I heard it, I pictured Wolverine-level repairs. Reality check: it’s just a snug fit around the nail, but hey, better than felt flapping around after a storm.

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“If it looks wavy before shingles, it’ll look worse after.”

- Humidity is brutal here (central Missouri), and those thinner synthetics are basically wrinkle magnets. I’ve had to redo sections because they bunched up so bad under the shingles. Not fun when you’re trying to keep costs down.

- Haven’t braved recycled underlayment yet either. I’m all for green options, but if it means more call-backs or leaks, I’ll pass for now. Maybe in a garage or shed first...

- Heavier stuff seems to lay flatter and doesn’t stretch as much in the heat. Costs a bit more, but fewer headaches later.

- Anyone else notice some brands get slick as ice when wet? Nearly did the splits last summer - felt like a cartoon character.

Had a crew rush through underlayment once and the roof looked like a potato chip.

That “wavy before shingles” line really hits home. I learned the hard way, too - my roof looked fine from the driveway, but up close it was a rollercoaster. Humidity here in southern Illinois isn’t much different from Missouri, and those thin synthetics just don’t stay put when it’s muggy. I’ve had better luck with the heavier stuff as well. Costs more up front, but I’d rather avoid doing the same job twice... plus I’m not getting any younger crawling around on a hot roof. Slick surfaces are no joke either - thought I was going to end up in the bushes last summer.

- Been there with the “potato chip” look - nothing like seeing your handiwork from the street and thinking it’s fine, then realizing it’s all waves up close.
- I’m with you on the heavier underlayment. Costs more, but I’d rather pay once than fight with it later, especially when it’s 95° and humid.
- Those slick synthetics are a slip-n-slide in the summer. Nearly lost a tool (and my dignity) last July.
- Only thing I’ll add - sometimes the lighter stuff is okay for quick jobs or sheds, but for a real roof, I stick with the thick rolls. My knees thank me.

- Heavy underlayment’s been a game changer for me too. Did my last roof with the thick stuff and haven’t had a single soft spot or weird wrinkle, even after a couple of nasty storms.
- I get why folks use the lighter rolls for sheds or quick fixes, but on a main house? Not worth the gamble. Had to patch up a neighbor’s roof last year - he went cheap and it was already curling up after two summers.
- Those synthetic ones are slick as heck in the heat. Nearly slid right off my own porch roof trying to grab a runaway hammer. Not fun.
- Only thing I wonder - anyone tried those “peel and stick” underlayments? I’ve heard mixed things about how they hold up long-term, especially in places with big temp swings. Worth the extra cost, or just marketing hype?

Heavy underlayment really does make a difference, especially in areas with wild weather swings. I’ve seen fewer issues with leaks and deck rot on homes that went with the thicker stuff. Peel-and-stick has its place - great for valleys or low-slope spots - but in my experience, it can get brittle after a few years if your climate goes from freezing to blazing hot. Not sure I’d use it everywhere, but as an extra layer where water tends to sneak in? Makes sense. Just gotta watch out for installation mistakes since once it’s down, it’s tough to reposition.

Can’t argue with thicker underlayment - definitely noticed less drama with leaks on jobs where we used it. Totally agree peel-and-stick is a lifesaver for valleys, though I’ve seen it go a bit crunchy after a few rough winters. It’s wild how much climate messes with stuff that’s supposed to be “weatherproof,” right?