Hot take: Hand troweling a slab in 95 degree heat like my old man taught me is dumb

I tried it last August on a driveway in Phoenix. Mix was setting up before I could even get a good finish on it. The old way he showed me with the long strokes and waiting for the bleed water just turned into a mess. Ended up with a rough surface that took twice as long to grind down. My neighbor who runs a crew out of Mesa told me I should have used a power trowel with a spray bar and some evaporation retardant. I learned the hard way that the old methods don't always work when the concrete is cooking in the sun. Has anyone else had this happen when they tried to follow old timers advice on a hot day?

2 comments

2 Comments

umaadams1d ago

Read a study from the Arizona PCA that showed bleed water evaporates 60% faster when temps hit 95 degrees or more. That's why your finish went to hell - the water leaves before you can work it. Tried that same trick my grandpa taught me here in Tucson last June on a small patio, and I swear the concrete was setting up like cookie dough within 15 minutes. Power trowel with the spray bar is the way to go down here, or just wait until November like my crew does.

emma_hart1d ago

My grandpa used to say "if you can fry an egg on the sidewalk, don't pour concrete." @umaadams hit it right on the head there. Those 95 degree days turn your pour into a race against the sun.