Which holds up better over time: felt or synthetic underlayment?

felt’s forgiving nature is a big plus. Synthetics claim longer life, but they can be a pain when you have to fix even a small tear.

Man, you nailed it with that. I’ve seen more than one homeowner try to patch synthetic after a branch went through it - usually ends up looking like a duct tape art project. Felt’s not perfect, but at least you can slap on a patch and call it good. That said, after last year’s hailstorm, I did notice the synthetic held up better where it wasn’t already torn... so maybe there’s something to those “longer life” claims if you’re not dealing with constant repairs. Still, for quick fixes and peace of mind, felt’s hard to beat.

I get where you’re coming from, but honestly, I’ve seen synthetic outperform felt in the long run, especially on steeper roofs or spots that get hammered by sun. Yeah, patching felt is easier, but if you’re having to patch a lot, maybe the real issue is the underlayment choice in the first place. I’ve had fewer callbacks for leaks with synthetic, even if it’s a pain to fix a tear. Just my two cents - sometimes the hassle up front pays off later.

- Gotta say, I’m still leaning toward felt for my own place.
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“sometimes the hassle up front pays off later.”

Makes sense to stick with what’s worked for you, especially if your climate and roof pitch aren’t pushing felt to its limits. I get the hype around synthetic, but honestly, the price can be hard to swallow if you’re not seeing big benefits. I’ve seen plenty of older homes where felt has lasted longer than folks expected - guess it really depends on the roof and how well it’s installed. Patching felt is definitely less of a headache too. No shame in going with the budget-friendly route if it’s holding up.

I get where you’re coming from. I was leaning toward synthetic at first, but the cost made me pause too. My neighbor’s house is 30+ years old with just felt, and it’s still holding up fine. Sometimes the tried-and-true stuff really does last if it’s put on right.

- Had the same debate last year. Ended up going with synthetic, even though it cost more.
- My old roof (asphalt shingles, Midwest climate) had felt for 25+ years. It did its job, but I noticed it started to wrinkle and break down under a few leaks.
- Synthetic’s lighter and way easier to handle, especially on steeper slopes. Didn’t tear as easily when I was crawling around up there.
- Yeah, felt can last ages if installed perfectly, but I’ve seen it fail early after a bad storm or two.
- Honestly, if you’re planning to stay in the house long-term, that extra cost for synthetic might be worth it... less landfill waste too.

Had the same dilemma when I replaced my roof a few years back (asphalt shingles, northern Illinois). Ended up going with synthetic too. The weight difference alone made a huge difference - felt was always a pain to haul up the ladder, especially on windy days. One thing I noticed: after a couple of rough winters, the synthetic didn’t show any of the bubbling or tearing I used to see with felt. That said, if you’re on a tight budget and your roof isn’t super steep, felt can still do the job... just gotta keep an eye out for leaks and fix them quick.

I get the appeal of synthetic, but I’ve seen a few jobs where it actually got slippery as heck when wet - made repairs a pain. Felt might not last as long, but sometimes it’s just easier to patch up if you spot an issue early. Guess it’s a trade-off, especially with all the freeze-thaw cycles up here.

That slippery synthetic is no joke - nearly wiped out trying to patch a spot after a rainstorm last fall. I do like that it’s lighter and goes down faster, but I’m with you: felt’s easier to cut and patch, especially when you’re up there solo. Ever notice if the synthetic gets brittle after a couple winters? I’ve only used it on one shed so far, so not much long-term data yet...

Yeah, that synthetic stuff is like trying to walk on a greased-up slip’n’slide - ask my bruised ego from last summer. I’ve had it on my garage roof for about three years now, and honestly, it’s holding up okay, but I do notice it feels stiffer than when I first put it down. Not cracking yet, but I’m in the Midwest, so we get those freeze-thaw cycles. Felt always seemed more forgiving if you had to patch or overlap. Synthetic’s lighter, sure, but sometimes I miss the old-school stuff when I’m up there cursing at the wind.

Man, I hear you on the slip’n’slide comparison. The first time I tried walking across synthetic in the morning dew, I nearly invented a new dance move - pretty sure my neighbors are still laughing. I put down synthetic on my shed last year, mainly because it was so much lighter to haul up there compared to the classic felt rolls. But yeah, it does feel a bit... plasticky? Harder to get it to lay flat, especially when the wind picks up and you’re wrestling it like a giant tarp.

I’m in Ohio, and we get that same freeze-thaw nonsense. My old house had felt under the shingles and, honestly, I patched that thing more times than I care to admit. But at least with felt, you could slap on some extra and not worry about fancy tapes or special overlaps. The synthetic seems tougher but less forgiving if you mess up a spot.

I guess for me it comes down to what kind of roof I’m dealing with. For a quick job or something I might have to patch later, I’d still go felt. For anything bigger where lugging rolls isn’t fun, synthetic wins. Neither’s perfect, but both keep me off the couch and out of trouble... most days.

That plasticky feel on synthetic gets me too - almost feels like you’re laying out a pool liner up there. I do like how tough it is, though. I’ve had squirrels try to chew through both, and the synthetic held up way better (felt was toast). But yeah, if you miss a staple or get a weird wrinkle, it’s not as forgiving. For my old garage roof, I went with felt just because it was easier to patch and didn’t care if it looked a little rough. On the main house, though, synthetic’s lighter weight made the job way less of a backbreaker. Both have their headaches... guess it’s just picking which ones you want to deal with.

I totally get what you mean about that plasticky feel - synthetic is weird at first, but man, it does take a beating. I went through the same debate on my shed. Ended up with synthetic just because dragging those heavy felt rolls up a ladder was brutal. It’s not perfect, but it sure is tough. You made the right call going lighter for the main house.

It’s not perfect, but it sure is tough. You made the right call going lighter for the main house.

I get the appeal of synthetic - lighter and easier to handle, sure. But honestly, I stuck with felt for my main roof because it’s way cheaper and still does the job if you install it right. That plasticky stuff might last longer, but when you’re watching every dollar, felt’s hard to beat. If you’re not dealing with crazy storms or super steep slopes, I don’t see synthetic as a must.

Felt’s definitely got its place, especially if you’re keeping an eye on costs. I used it on my old bungalow and it held up fine for years - no leaks, even with our rainy springs. As long as you’re careful with the install and don’t have wild weather, it’s a solid choice.

That said, I do like that synthetic underlayment is lighter and doesn’t wrinkle up as much if it gets wet before the shingles go on. But yeah, the price difference is real. For folks who aren’t in hurricane zones or dealing with crazy temperature swings, felt can be a smart move.

I’m always rooting for greener options, though - if you ever spot recycled-content synthetics or felts, those are worth a look. Either way, sounds like you made a practical call for your situation. Sometimes “good enough” really is good enough.

- Both felt and synthetic have their quirks - here’s how I see it after a couple decades on roofs:

- Felt’s been around forever. It’ll do the job if you install it right and don’t leave it exposed too long. But if you get a surprise rainstorm before shingles go on, it can wrinkle or even tear. Seen that more than once... not fun to fix.

- Synthetics are lighter, tougher, and honestly, way easier on the back when you’re hauling rolls up a ladder. They don’t absorb water, so no weird bubbles or soft spots if the weather turns on you mid-project.

- Price is definitely higher for synthetics, but I’ve noticed they hold up better if there’s any delay between underlayment and shingles. If you’re in a spot with unpredictable weather (looking at you, Midwest), that peace of mind can be worth it.

- For “green” options, I’ve seen some recycled-content synthetics lately - still waiting to see how they last long-term, but promising.

- End of the day, both work if installed right. If budget’s tight and you can shingle quick, felt’s fine. If you want less hassle and longer exposure time, synthetic wins for me.

I get the appeal of synthetics, especially with unpredictable weather, but I’ve seen some issues crop up after major hail or wind events. Some of the lighter synthetics can actually tear or flap if they’re left exposed too long, and I’ve had a couple insurance inspections where the underlayment didn’t hold up as well as expected. Felt isn’t perfect, but in certain storm-prone areas, the heavier grades can sometimes take a beating better than folks expect. It really depends on the specific product and how long it’s exposed before shingles go on.

- Had this same debate with my contractor last fall. Ended up with synthetic since everyone said it was “the new standard,” but I’m still not totally convinced it’s always better.

- Live in the Midwest, so hail and wind are a real thing here. My neighbor’s roof got hit hard last spring - his synthetic underlayment was flapping around after just a few days of exposure when the shingles delivery got delayed. Felt like that stuff should’ve held up better.

- On the flip side, my parents’ old house had heavy felt underlayment. It looked rough after a big storm, but didn’t actually tear or go anywhere. Maybe it’s just luck or maybe the heavier felt is tougher than people give it credit for.

- The synthetic definitely went on faster and was lighter to haul up there, but now I’m wondering if I should’ve pushed for the thicker felt, at least as a backup in case of delays.

- Insurance adjuster didn’t say much about it, but I keep hearing stories about claims getting tricky if the underlayment fails before shingles are installed.

- Honestly, if I had to do it again, I’d probably ask more questions about which brands hold up best during those “in-between” days before the roof’s finished. Not sure there’s a perfect answer... just wish someone would invent something that actually lasts through a stormy week without drama.

I keep wondering if the “new standard” label for synthetics is more about convenience than actual performance, especially in places with wild weather swings. I’ve seen some of those synthetics shred after a couple days of sun and wind, while old-school felt just kind of sags but stays put. Maybe it’s not as high-tech, but sometimes the heavier felt seems to take a beating better - at least for those awkward gaps between tear-off and shingle install. I do wish there were more options that balanced durability with environmental impact, though... most of these products aren’t exactly eco-friendly.

I’ve seen some of those synthetics shred after a couple days of sun and wind, while old-school felt just kind of sags but stays put.

Totally get this. Had a stretch last summer where my roofer left synthetic up for a week - looked like confetti after three days of those “gentle” Midwest gusts. Felt might look sad sagging there, but at least it doesn’t end up in my neighbor’s yard. Not saying felt’s perfect, but sometimes “old-school” just survives the chaos better. Wouldn’t mind if any of them were less landfill-bound though...