Weighing the pros and cons: full roof removal vs. just adding a new layer

You’ve nailed a lot of the big issues here. I’ve seen too many homes after a heavy storm where that “just add a layer” shortcut turned into a real headache - sagging rafters, cracked ceilings, even some bowing walls in older places. The weight adds up fast, especially with wet snow or ice on top.

Tear-offs are messy and nobody loves the extra labor, but you’re right about the hidden problems. Last fall, I worked on a 1950s ranch where we found rot around two valleys and a bunch of rusty nails that had almost eaten through the sheathing. If we’d just gone over the old shingles, those spots would’ve kept getting worse until there was a real leak.

Flashing’s another thing folks overlook. I’ve seen “new” roofs leak at the chimney just because the old flashing was left in place and failed during the first freeze/thaw cycle. It’s tempting to save money up front, but it can cost more down the line.

I get why people want to avoid the hassle, but unless you’re dealing with newer construction and solid framing, tear-off is usually worth it for peace of mind.

Yeah, I’m with you on the tear-off being worth it, even if it’s a pain. I tried the “just add a layer” thing years ago on my old shed - figured it’d be quicker and cheaper. Regretted it after the first winter. The snow here in upstate NY gets heavy, and that extra weight made the rafters creak like crazy. Ended up having to redo the whole thing anyway because water found its way in around some old flashing that I didn’t bother to check.

One thing I didn’t really think about until I did a full tear-off on my house: you can actually see what’s going on underneath. Found a couple of soft spots in the plywood that would’ve just kept rotting if I’d left them covered up. It’s kind of wild how much damage can hide under shingles that look fine from the ground.

I get why people want to save money or avoid the mess - tearing off is loud, messy, and takes forever if you’re doing it yourself. But at least you know what you’re dealing with when you’re done. Plus, I’ve heard some insurance companies won’t cover damage if there’s more than two layers of shingles? Not sure if that’s everywhere, but it was definitely something my adjuster mentioned after a hailstorm last year.

Only exception I’d maybe consider is if your roof is pretty new and just needs a cosmetic refresh, but honestly, most of the time it seems like kicking the can down the road. Especially in places where we get ice dams or big storms... problems just get worse under there.

Curious if anyone’s had luck with those synthetic underlayments instead of felt? My neighbor swears by them but I haven’t tried it yet.

Ended up having to redo the whole thing anyway because water found its way in around some old flashing that I didn’t bother to check. One thing I didn’t really think about until I did a full te...

I get where you’re coming from, but I’ll be honest - I did a second layer on my garage roof about 8 years ago and it’s held up fine. Granted, it’s a low-traffic area and we don’t get as much snow as upstate NY, but for me the cost savings were worth it. Not saying it’s always the right call, but sometimes “kicking the can” buys you enough time to save up for a proper tear-off later. Just gotta know your limits and check local codes.

sometimes “kicking the can” buys you enough time to save up for a proper tear-off later

That’s pretty much how I look at it too. On some of my rentals, layering bought me a few extra years without major leaks. But I always double-check the flashing and edges - skipping that step bit me once, and it wasn’t fun. Local codes are key, though... some places just won’t allow a second layer.

That’s a good point about the flashing - honestly, I’ve seen more problems from rushed edge work than from the extra layer itself. I get why people go for a second layer to buy time, especially with prices where they are now. But I always wonder about the long-term energy impact. Two layers can trap more heat, which isn’t great for cooling bills or shingle longevity. If you’re thinking about solar or cool roofing down the line, a full tear-off might actually pay off sooner than expected. Local codes are all over the map on this, though... sometimes it’s just not your call.