If I ever have to do it again, I’m leaning toward full tear-off, even if it stings the wallet at first. Just feels safer knowing what’s actually under there.
That’s a pretty common takeaway after dealing with hidden issues like rot or nests between layers. I’ve seen a lot of roofs where a second layer seemed like a quick fix, but it just masked bigger problems underneath. Once you start pulling things apart and find soft decking or old moisture damage, it’s clear why the extra upfront cost can be worth it.
One thing that gets overlooked is ventilation. When you add another layer, you’re trapping more heat and moisture, especially if the original roof wasn’t vented well to begin with. That can speed up deterioration of the wood deck and even the new shingles. In colder climates, ice dams get worse too. I’ve had clients in the Midwest who thought they were saving money, but ended up with warped sheathing and mold issues a few years later.
That said, I get why people go for the overlay—sometimes budgets are tight or you just need to buy a little time before a bigger renovation. But if you’re planning to stay in the house long-term, or if you’re already seeing soft spots, a full tear-off is usually the safer bet. You get to inspect the decking, replace any bad wood, and install new underlayment. Plus, most shingle manufacturers only honor their full warranty on a single layer.
Funny about the glove and bird’s nest... I once found an old lunchbox wedged between layers on a job. No idea how it got there, but it was definitely from another era.
If you do go for a tear-off next time, just be prepared for some noise and mess—it’s not fun living through it, but at least you know exactly what you’re working with when it’s done. And yeah, dumpster fees aren’t cheap these days... but neither is replacing half your roof deck after the fact.
But if you’re planning to stay in the house long-term, or if you’re already seeing soft spots, a full tear-off is usually the safer bet.
I wrestled with this exact thing last year. My roof had two layers—previous owner just slapped new shingles on top of old. Looked fine until we noticed a sag near the gutter. Pulled back a section and, sure enough, the decking was mushy. Ended up doing a full tear-off, which hurt the wallet but honestly, I sleep better knowing there’s no hidden rot up there. The mess and cost were rough, but I’d do it again over risking more damage down the line.
Had a similar situation—old asphalt shingles, two layers, and some spots felt bouncy when I walked the roof. Here’s what I ran into:
- Pulled up a few shingles and found damp decking, just like you mentioned:
“the decking was mushy”
- Full tear-off let me actually see what was going on underneath. Found some small leaks I’d never have spotted otherwise.
- More expensive upfront, but the peace of mind’s worth it. Plus, warranties are usually better when you do a tear-off.
- Downside: way more debris and took longer than I expected. Dumpster rental was a must.
If you’re seeing soft spots or plan to stay put awhile, I’d lean tear-off too. Layering just hides issues, in my experience.
