That’s a good point about finding rot—
That’s the part that always makes me hesitate with layering. Sure, it’s cheaper and less mess, but what’s hiding under there? I’ve seen folks do a second layer and then get hit with leaks after a big storm, only to find out the decking was shot. On the other hand, if your roof’s in decent shape and you’re not seeing any sagging or soft spots, is it always necessary to tear everything off? Sometimes I wonder if the “always strip it” advice is a bit overcautious, but then again, you don’t know what you don’t see.“Found a patch of rot near the chimney that would’ve gotten way worse if I’d just covered it up.”
“you don’t know what you don’t see.”
That’s exactly what gets me. My uncle once did a layover on his old ranch house, figured the decking was solid since there were no leaks or soft spots. Two years later, a raccoon found a weak spot and made it a whole lot worse. Makes me wonder—how do you really know if the decking’s good without pulling at least some of it up? Or is there some trick for checking underneath without going full demo?
That’s the million-dollar question, isn’t it? I’ve crawled around more attics than I care to admit, and honestly, you’d be surprised how often things look fine from above but are a mess underneath. I once inspected a place where the shingles were only five years old—looked great from the street. But up in the attic, daylight was peeking through a couple of spots where the decking had rotted out. No leaks yet, but it was just a matter of time.
Short of pulling up shingles, the best you can do is poke around in the attic with a flashlight. Look for staining, sagging, or any spots that feel soft if you can reach them (careful not to go through the ceiling—ask me how I know). Sometimes you’ll spot old water marks or even smell mildew before you see anything obvious. But yeah, unless you’re pulling up at least a few shingles, it’s mostly educated guesswork. Raccoons, squirrels, and time have a way of finding every weak spot you miss...
Funny you mention raccoons—I've seen more than one spot where critters did more damage than the weather ever did. I get why folks want to just layer new shingles and call it a day, but if the decking's soft or there's hidden rot, that's just putting a band-aid on it. Have you ever run into a situation where the second layer actually hid a bigger problem? Sometimes I wonder if local codes about tear-offs are strict enough, especially in places with heavy snow loads.
I’ve definitely seen second layers hide some nasty surprises. Once helped a neighbor pull off a “quick fix” shingle job and found half the decking was basically mulch—critters had tunneled in, and the moisture just sat there. It’s tempting to just slap another layer on, especially when you’re staring down a big bill, but if you don’t check the wood underneath, you’re rolling the dice.
I get why codes aren’t always strict—some places just don’t see the same snow or rain we do up north. But heavy snow’s a different beast. Extra weight on already-soft decking is asking for trouble. I’m all for stricter tear-off rules in those climates, honestly.
Ever notice how much more heat gets trapped with two layers, too? Not great for energy bills or shingle life. Curious if anyone’s had luck convincing an insurance adjuster to cover a full tear-off when there’s hidden rot? That’s always been a headache around here.