Reflective tarps are one of those things that sound great in theory, but in practice... mixed bag. I’ve tried them a couple times on bigger jobs where we had to work through a heat wave. They do help knock the edge off if you’re waiting for a spot to cool down before welding, but honestly, hauling them up and keeping them from blowing around was almost more hassle than it was worth. If you’ve got a big, open area and a crew to help, maybe. For small repairs or patch jobs, I’d rather just shift my schedule and avoid the hottest part of the day.
You’re right about the hand test—simple but effective. I’ve seen guys chasing numbers with infrared guns, but at the end of the day, if you can’t touch it, your weld’s probably going to be sketchy. Early mornings are my go-to too, especially on white TPO. The surface cools off quick once the sun dips behind a cloud or late afternoon rolls around.
If you’re dealing with brutal sun and no shade options, I’d say try a tarp once just to see if it fits your workflow. Otherwise, working smarter hours beats lugging extra gear any day.
I’ve wrestled with those tarps too, and honestly, half the time I end up chasing them across the roof when a gust picks up. I get why folks try them, but like you said, shifting your hours just makes more sense most days. I’ve had better luck just waiting for the sun to dip or starting before it’s fully up—especially on those blinding white TPO jobs. The hand test is old school but it’s saved me from some ugly seams more than once. Sometimes simple really is best.
Yeah, those tarps are about as useful as a screen door in a submarine once the wind picks up. I tried the early morning approach last summer when we had that stretch of 90+ days—way easier on the budget than buying more gear or burning through extra material from bad welds. My neighbor swears by fancy gadgets to measure temp but honestly, the back-of-the-hand test hasn’t let me down yet. If it feels like you could fry an egg on it, it’s probably too hot for decent seams. Sometimes you just gotta keep it simple and trust your gut.
If it feels like you could fry an egg on it, it’s probably too hot for decent seams.
That’s pretty much the gold standard in my book. I’ve tried those fancy infrared thermometers, but half the time I’m just chasing numbers while the sun’s baking my neck. Last July, I was up on a white TPO roof at noon (bad idea, I know), and my boots were sticking to the membrane like gum on hot pavement. Tried to run a seam anyway—looked fine at first, but by the next rain, it peeled up like a sticker. Lesson learned.
Early mornings or late afternoons are way less stressful. I’ll admit, I still keep a temp gun in the truck for those “just in case” moments, but nothing beats that back-of-the-hand check. If you can’t keep your hand on it for more than a second, time to grab some shade and wait it out. Sometimes simple really is smarter than all the gadgets.
If you can’t keep your hand on it for more than a second, time to grab some shade and wait it out. Sometimes simple really is smarter than all the gadgets.
- "Sometimes simple really is smarter than all the gadgets." — I get where you're coming from, but I've seen a few jobs go sideways when folks relied just on feel.
- Surface temp can be deceiving, especially with different TPO colors or cloudy days.
- Temp gun's not perfect, but it gives a baseline. I always double-check with it before signing off on welds.
- Seen seams look great at first, then fail inspection because the substrate was hotter than expected. Just my two cents.
