Once my TPO started feeling tacky, I called it quits as well. It’s just not worth risking bad seams and leaks later.
Totally agree with this. When the membrane gets sticky, you’re basically fighting a losing battle—welds just don’t hold up right, and you end up redoing work anyway. I’ve tried using those pop-up tents, too. They look ridiculous from the street, but honestly, anything to avoid that “muggy tarp sauna” situation... Still, when the surface temp is pushing 140°F, I’d rather reschedule than risk a warranty headache down the line.
I get the concern about sticky TPO, but I’ve actually managed to get decent welds on hot days by adjusting the welder temp and speed. Not ideal, but sometimes you just have to work with what you’ve got.
I hear you, but in my case, waiting wasn’t an option—summer storms were rolling in. I just made sure to double-check every seam as I went. Not perfect, but so far, no leaks.“when the surface temp is pushing 140°F, I’d rather reschedule than risk a warranty headache down the line.”
I’ve seen some pretty wild stuff when it comes to welding TPO in the heat. One crew I inspected last July was working on a school roof in the middle of a heatwave—surface temp was reading close to 150°F. They tried to compensate by cranking down the welder, but you could see right away some of the seams were just too glossy and soft. Sure, they looked okay at first glance, but when I ran my probe along the laps, a few spots peeled up like warm cheese.
I get not always having the luxury to wait—weather doesn’t care about your schedule. But man, I’ve seen more callbacks from rushed hot-weather welds than just about anything else. Sometimes you can get away with it if you’re really careful and double-check every inch, but it’s a gamble. If you do have to push through, at least try to work early or late when the roof’s cooled off a bit. Otherwise, you’re just rolling the dice with future leaks... and nobody likes that surprise during an inspection.
I hear you on the callbacks, but I’ve actually had a few jobs where we had no choice but to weld TPO smack in the middle of a scorcher. Not ideal, but sometimes the schedule’s got you by the... well, you know. What saved us was dragging out some big tarps and hosing down the roof ahead of time—looked ridiculous, but it kept the surface temp down enough to get decent seams. Not saying it’s foolproof, but it beat waiting for a cold front that never came. Sometimes you gotta get creative or you’ll be waiting forever.
Dragging out tarps and hosing down the roof? That’s some next-level MacGyver stuff, I’ll give you that. But I gotta ask—aren’t you worried about messing with the warranty or having the seams fail later? I’m always paranoid when it comes to anything on the roof because, let’s be honest, I don’t want to pay for the same job twice.
When I had my TPO done last summer, the crew flat-out refused to weld above 90°F. They said the risk of voiding the warranty or getting bubbles was just too high. It meant waiting around for a few cooler mornings, which was annoying, but at least I slept better after. Maybe I’m just too cautious (or cheap), but the thought of water sneaking in through a bad seam keeps me up at night.
Does anyone actually check with the manufacturer before doing these workarounds, or is it just cross-your-fingers and hope for the best?