Had the same sticker shock when I saw the price for synthetic underlayment. My wallet basically tried to run out the door. Ended up going with felt because, well, I like eating food more than having a fancy roof liner. Midwest storms are no joke though, so I did worry about how long it’d hold up.
Funny thing—my neighbor went with the recycled cellulose stuff last year. He’s a “save the planet” type, but now he’s got this weird patch of mold in his attic that smells like gym socks after a rain. Not sure if it’s the cellulose or just bad luck, but it made me pause.
Warranties always feel like those extended car warranties—sounds great until you actually need them. My contractor said synthetic comes with a 30-year warranty, but I’ll probably move before then anyway... or the next hailstorm will turn my roof into Swiss cheese and void it all.
If underlayments could talk, mine would probably just sigh and ask for a vacation.
I hear you on the sticker shock—synthetic underlayment prices made me double-check my math more than once. I ended up splitting the difference: synthetic on the south-facing slope (gets hammered by sun and wind), felt everywhere else. Midwest weather is brutal, but honestly, the felt’s held up better than I expected. The cellulose mold thing is wild... I always wondered about moisture issues with those “green” options. Warranties sound nice, but between hail and squirrels, I’m not betting on 30 years either. At this point, I just hope my roof liner doesn’t file for early retirement.
That’s pretty much the same logic I used—synthetic where the sun hits hardest, felt everywhere else. I was super skeptical about felt at first, especially after hearing all the horror stories about it turning to mush after a few years. But honestly, mine’s been up for six Midwest winters and not a single issue so far. Maybe it’s just luck or maybe the newer felts are a bit tougher than they get credit for.
The cellulose thing is wild to me too. I wanted to go “green” but kept reading about mold and weird moisture problems. Didn’t want to risk that on a roof that already deals with ice dams half the year. Warranties always sound reassuring until you realize squirrels don’t care about paperwork, and hail will just void everything anyway...
I do wonder if synthetic really holds up THAT much better in the long run, or if it’s mostly marketing hype. My neighbor swears by his synthetic underlayment but he also re-roofs every 10 years “just in case,” so who knows.
Warranties always sound reassuring until you realize squirrels don’t care about paperwork, and hail will just void everything anyway...
That line about squirrels and hail got me—so true. I’ve seen more roofs “voided” by critters than anything else. On the synthetic vs felt debate, I’ve torn off a lot of both over the years, and honestly, I’m not convinced synthetic is always the magic bullet it’s made out to be. Some of the older felts (the heavier stuff, not the cheap #15) have held up surprisingly well under shingles for 20+ years, especially if the attic’s ventilated right.
But then again, I’ve also seen synthetic underlayment come off looking almost brand new after a decade, even on steep south-facing slopes. The main thing I notice is that synthetic handles water intrusion better during install—if you get caught in a downpour mid-job, it buys you more time.
That said, if you’re in the Midwest with ice dams and freeze/thaw cycles, I’d still lean toward synthetic in trouble spots. But I wouldn’t write off felt everywhere else. Sometimes it’s just about how well the whole system’s put together, not just the underlayment itself.
Sometimes it’s just about how well the whole system’s put together, not just the underlayment itself.
That’s the part that really sticks with me. You can have the fanciest synthetic or the thickest felt, but if the install’s sloppy or the attic’s a sauna, it won’t matter much. I’ve patched up more than a few “premium” roofs that still leaked because of bad flashing or poor ventilation, not the underlayment itself.
I’m with you on the Midwest thing—ice dams are brutal. I’ve seen synthetic save a lot of headaches there, especially when snow sits for weeks. But I’ve also pulled up old 30# felt that looked way better than I expected, even after decades. Sometimes I think folks get too caught up in the latest product hype and forget that a solid install and regular checks go a long way.
Critters, though... nothing seems to stop them. Had a raccoon tear through both synthetic and felt last year like it was tissue paper. At that point, paperwork and warranties are just for laughs.