derekjenkins•16d agoProlific Poster

That stamped concrete job near Memphis last July taught me a lesson about timing

I poured a 400 square foot patio with a stamped slate pattern near Memphis last July, and the heat got to it faster than I expected. The stamp stuck to my tools because the surface set up in about 20 minutes instead of the usual 45, and I had to scramble to fix the lines before it was too late. Has anyone else dealt with rapid setting in hot weather, and what's your trick to keep the surface workable longer?

3 comments

3 Comments

jana_fox5016d ago

Throw in some ice cubes next time and pretend you're making a fancy cocktail.

nancy_ross16d ago

The sugar trick is something I've heard about for years, but I always wondered if it actually works the same as a commercial retarder. @jana_fox50 that ice cube idea might be good for a laugh, but it won't help the chemistry much. Ellis.mia, you mentioned wetting the base and forms before the pour - how many extra minutes do you typically get from that? I've tried it a few times and it seems like maybe five minutes at best, but I'm never sure if it's really doing anything or if I'm just imagining it. Also, have you ever had a batch plant give you pushback when you ask for a retarder in the mix? I always feel like they act like it's a big hassle, but it seems like a simple thing to add.

ellis.mia16d ago

Oh boy, that's a rough one. Something nobody's bringing up is your mix design - if you used a standard bag mix off the shelf without adjusting the retarder, you're basically fighting the sun with one hand tied. In summer heat, you gotta spec a mix with a set retarder added at the batch plant or toss in a cup of sugar per yard of concrete to slow things down. Even just wetting the base and forms with a hose before you pour buys you another 10 minutes of workable time. Sounds like you were fighting the concrete chemistry more than the temperature itself.