Hi..I am reading all about the bad results of working with concrete in freezing weather and wonder if anyone can explain this. I had footing for pool coping installed in the winter. They were 12" wide by 7.5 inches deep. It was always cold during the day,and as I recall not that much over 40, but possibly sunny. There was no protection given to prevent freezing..The temps went down to 18-20 degrees :surprise: the nights of the pours which was not a pour but wheelbarrow and hoe. They finished late in the day and freezing temps came very quickly..The concrete now needs to be cut back to 8". The concrete is extremely hard and will go through more than 3 14" diamond blades if we continue. No one planned on this..The contractor now wants more money. The question is can doing the concrete in freezing weather cause it to be harder than it should be or maybe the mix was heavy with one part. When they poured it they started with bags for about 25 lin ft. then went to the mixer. They were slow..They have not tried to cut the bagged section only the mix that was done by shovelfuls as the measure. I do not know the mix they used for the unbagged portion which is the majority. So why is it so G-D hard? Thanks.