when I heard wire grid, and fiber in the concrete that's all I needed to know it was a cheap fast job over a packed sub-surface.
I've done a lot of concrete over the years. There's a lot, a lot, a lot of prep for putting in concrete where there is a significant chance of frost more than 2" below surface. The damage could almost be predicted, and here's another thought - it'll likely happen again.
Grading, tamping, gravel substrate, vertical bore holes, rebar on 8" centers, 5000PSI mix, checked with a slump cone, and so on and so forth.
It can be done right, in Vermont, and Denmark, and Iceland and it will NOT heave. But - to do this right the cost more than doubles, and in some cases would triple what was likely paid for this buddy/neighbor doing the job on the cheap.
Concrete runways are built all over the cold climates and they rarely crack or heave. But - they are 16" thick, with 5000PSI or better, over a very carefully designed substrate.
edit: Here's a 22x38' driveway I did in 2004. It's at 8400' elevation in N CO. We get days at a time below freezing and have had several days below zero F. Not a crack, not a craze, not a bit of movement in almost 20 years. It's 8" thick, on 12" rebar centers, with a 6" frost edge and sits 3" proud of the surrounding ground. It was poured with 4500PSI, and yes, I did reject the first truckload for being to thin, and flowing out the slump cone. He didn't have a word to say driving back and dumping that useless load of junk.
This post was edited by docmirror on 02/09/2023 at 05:38 pm.