Moisture meters can be a bit like fortune cookies—sometimes you get something useful, sometimes it’s just confusing. I’ve had the same issue with attic humidity throwing things off. Honestly, your screwdriver test is old-school but solid. If the decking feels sturdy and you’re not seeing any mushy spots, layering can be a win for both your wallet and the planet. Just gotta trust your gut (and maybe your screwdriver) more than those gadgets sometimes.
I get the appeal of trusting your gut and a trusty screwdriver—sometimes those gadgets just make things murkier. But I’ve seen a few roofs where the decking *seemed* solid, only to find hidden rot once we started pulling shingles. If you’re layering, I’d suggest at least popping a few test holes in different spots, especially near valleys or chimneys. It’s a pain, but it can save you from surprises down the line. Sometimes what you can’t see (or poke) really does come back to bite...
That’s spot on—hidden rot is a nightmare, especially after hail or wind events. I’d add, even if the decking feels solid, moisture meters can sometimes pick up what a screwdriver misses. Around chimneys and valleys, water finds its way in over time... seen it too many times to skip checking. Layering can hide a lot of sins under the surface.
Layering can hide a lot of sins under the surface.
That’s exactly what freaks me out about just slapping new shingles on top. I had a roofer try to talk me into layering, but after poking around the attic and seeing some old water stains near the chimney, I just couldn’t trust it. Maybe it’s overkill, but I’d rather rip everything off and know what’s actually going on underneath. The idea of “hidden rot” makes me think you’re just kicking the can down the road—especially in places with wild weather swings like we get here.
I get that it costs more upfront, but I’d rather deal with that than surprise repairs later. Anyone else feel like contractors sometimes push layering just because it’s faster for them?
I get where you’re coming from, but I don’t think layering is always a shortcut or a bad call. There are situations where it actually makes sense—like if the existing shingles are still lying flat, there’s no sign of rot or leaks, and the roof structure is solid. It can save a lot of mess and money, especially if you’re not planning to stay in the house for decades.
That said, you’re right about hidden issues. If you’ve already seen water stains in the attic, that’s a red flag. In those cases, tearing off is the safer bet. But I’ve seen plenty of roofs where layering was done right and held up just fine, even through some nasty storms. I think it really comes down to what’s going on underneath and how much risk you’re willing to take.
Not every contractor is just trying to rush the job, but yeah, some definitely push for the faster route. Just gotta weigh the pros and cons for your own situation.