The week my foundation pour went completely wrong

Sam Murphy · 2026-06-07T20:05:03.494515+00:00

Last Tuesday in Phoenix, the concrete truck showed up 2 hours late and the temp had already hit 105 degrees. The mix started setting before we could even screed it, and we ended up with a 4 inch thick slab that looked like a waffle. Has anyone else dealt with hot weather concrete disasters and found a way to save the pour?

briancarter3mo ago

Man that's brutal. Down in Tucson I had a similar mess last July - we wound up mixing in some chilled water and ice to buy time while the finishers worked in shifts to get it down. The key is getting a retarding admixture from your supplier before they load, helps keep the set time manageable in extreme heat. Did you have to chip out that waffle or manage to get a resurfacer on it?

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maryt623mo ago

Chill that mix down hard before it leaves the yard. Ask for liquid nitrogen injection if your supplier offers it, drops the temp fast without messing with the water ratio. Also throw in a handful of set retarder and some ice in the mixer drum on the way over, that buys you an extra 20-30 minutes easy. For a pour that's already turning into concrete jerky, grab a power trowel with a bull float and hit it before it crusts over completely, then cover with wet burlap and plastic right after to slow the cure.

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angela_grant2mo ago

That pour was probably doomed from the start anyway. Phoenix in July is a BAD idea for concrete work, you should've known better than to schedule a pour without a solid plan for the heat. A little ice and retarder isn't going to save you when the truck's two hours late and the sun's cooking everything.

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