Weight gets overlooked way too often. Had a client with a 1940s bungalow—added a second layer thinking it’d save a buck, but you could hear the rafters groan every time the wind picked up. We ended up tearing both off a few years later anyway, and half the decking was mush from hidden leaks. Tear-off’s messy, sure, but I’d rather deal with the mess than risk hidden rot or code headaches. Plus, flashing and vents just seal better when you start fresh. Adding solar’s a whole other can of worms if you’ve got layers stacked up...
Weight gets overlooked way too often. Had a client with a 1940s bungalow—added a second layer thinking it’d save a buck, but you could hear the rafters groan every time the wind picked up.
That’s exactly what worries me about layering, especially on older homes. People underestimate how much extra load those shingles add, and it’s not just the rafters—insulation gets compressed, ventilation suffers, and you’re basically trapping any old moisture or mold right in the sandwich. From a sustainability angle, a tear-off lets you check for rot and upgrade insulation or even go with cool-roof materials. It’s a pain, but worth it long-term, especially if you’re thinking about solar down the line. Stacking layers just feels like kicking the can.
Had a place built in the 50s—classic low-slope roof, not exactly designed with “future-proofing” in mind. The previous owner decided to slap a new layer of shingles right over the old ones, probably thinking it was a clever shortcut. Fast forward a few years, and I’m chasing leaks every rainy season. Turns out, the extra weight wasn’t just a theoretical problem—one corner started sagging, and the attic looked like a sauna from all the trapped moisture.
I get why folks want to avoid the mess and expense of a full tear-off, but man, the hidden costs sneak up on you. Plus, it’s almost impossible to spot rotten decking or critter nests unless you strip it down. I’ve had contractors try to talk me into layering again for “efficiency,” but after seeing what happens firsthand...no thanks. Maybe on a newer build with beefier framing, but these old houses just don’t have much wiggle room.
On the plus side, the tear-off gave me a chance to add proper vents and insulation—now my heating bills are actually reasonable. Not glamorous work, but definitely worth it in the long run.
That’s wild—never thought about how much “hidden” stuff could be going on under old shingles until I started helping out on jobs.
Makes me wonder how many folks are just stacking problems without realizing. Glad you got the vents and insulation sorted, though. Did you notice a big difference in attic temps after?“it’s almost impossible to spot rotten decking or critter nests unless you strip it down.”
Yeah, attic temps dropped a good bit once we actually got the old junk out and put in proper vents. Before that, it was like stepping into a sauna every afternoon—even in spring. I’ve seen way too many folks just slap another layer on and call it a day, but then you’re basically sealing in all kinds of mess. One house I worked on, we found squirrel nests and half the decking was soft as a sponge. Not saying tear-off is always necessary, but man, sometimes you really don’t know what you’re hiding under there.
