- 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...