Found out the hard way that concrete cures differently in winter
I was pouring a sidewalk in Denver last December and didn't realize that below 40 degrees, the hydration process slows down by more than half. The supplier mentioned it when I called about the mix, and now I always check the forecast at least 3 days ahead. Has anyone else had a cold weather pour fail on them?
Hot water is my go-to trick too (mostly because I forget to plan ahead and end up rush-mixing at the last second). 40 degrees is actually balmy compared to the time I tried pouring at 32 and my wheelbarrow turned into a popsicle halfway across the yard. Let's just say that slab ended up looking like a topographical map of the Rockies.