Had a client last year who nearly lost his garage to a torch-down job gone wrong—installer got distracted, and the underlayment caught. I get why folks still use torch-down for flat roofs, but honestly, I’ve seen more fire scares than I’d like. Peel-and-stick isn’t perfect in the desert, but I’d rather deal with some bubbling than a fire risk. Green roofs are cool, but yeah, the install is no joke and not cheap either. Every option’s got its headaches.
Peel-and-stick isn’t perfect in the desert, but I’d rather deal with some bubbling than a fire risk.
That’s kinda where my head’s at too. I’ve only been around a couple torch-down jobs so far, but each time I’m just waiting for something to catch... The bubbling with peel-and-stick can be annoying, but is there any way to minimize that in hotter climates? Or is it just inevitable? Curious if anyone’s had luck with specific brands or prep tricks.
Bubbling with peel-and-stick in desert heat is definitely a headache, but I wouldn’t call it inevitable. Surface prep makes a huge difference—if there’s any moisture trapped, or the substrate isn’t totally smooth, bubbles are almost guaranteed once the sun hits. I’ve had better luck rolling out the membrane early in the morning when everything’s cool, and then pressing it down tight before temps spike. Some folks swear by priming the deck first, but I’ve seen mixed results.
Brand-wise, I’ve noticed some of the heavier granulated membranes hold up better, but they’re pricier. Curious if anyone’s tried venting methods under the membrane? I’ve seen a couple jobs where they used vented base sheets to help with vapor, but I’m not sure how much that actually helps in 110+ degree weather. Anyone run into issues with warranties when bubbles show up? That’s always in the back of my mind...
Curious if anyone’s tried venting methods under the membrane? I’ve seen a couple jobs where they used vented base sheets to help with vapor, but I’m not sure how much that actually helps in 110+ degree weather.
I wondered the same thing when I was sweating through my own roof project last summer. My neighbor tried those vented base sheets and honestly, his roof still looked like a bubble wrap experiment gone wrong by August. Maybe it helps a bit, but in our desert heat, it feels like nothing short of magic would keep those bubbles away. As for warranties, I read the fine print and it’s wild how fast they’ll blame “improper install” if anything pops up. Makes me paranoid every time I see a new lump up there...
- Gotta say, I’ve seen vented base sheets work out okay in some cases, especially where there’s at least a little bit of attic space or airflow. Not a cure-all, but sometimes it does help with those “bubble wrap” situations you mentioned.
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That’s rough. Usually, when I spot bubbles, it’s either trapped moisture or the substrate wasn’t totally dry before install. In my experience, vented sheets can help if the install’s done right, but they’re not a magic fix for every climate.“his roof still looked like a bubble wrap experiment gone wrong by August.”
- In 110+ heat, almost any membrane is going to struggle if there’s vapor underneath. I’ve seen some folks try double venting—like adding actual roof vents along with the vented base—but that’s not always practical or pretty.
- Warranties are a headache. Most manufacturers will look for any excuse to call it “installer error,” especially with torch-down. I always tell folks to document everything during install, just in case.
- One thing I’ve noticed: roofs with lighter-colored membranes seem to have fewer bubbles in extreme heat. Maybe worth considering if you’re redoing things down the line.
- Not saying vented base sheets are perfect, but I wouldn’t write them off completely. Sometimes it just comes down to how careful the prep was and whether the deck was bone dry before torching.