My name is XXXXX XXXXX I'd be happy to answer your questions today. I'm sorry to hear that this happened.
When a person makes an arrangement with a contractor to do work, the contractor has an obligation to do it in what is called a "workmanlike manner." If the contractor knew that it was too hot to pour the concrete and he did it anyway (unless you insisted that he do it), and it cracked as expected, then he can be legally required to repair or replace the work. If in doing so he damages other areas of the driveway, he'll also have to fix those.
If he refuses to fix the damage, then you have the option of suing for damages. What you would be entitled to is the cost of paying someone else to fix the work (because you should have had a completed driveway for the agreed contract price and not a penny more). If that is $3,000 or less, you can bring the suit in Small Claims Court
. If you have not yet finished paying the contractor, then you could withhold payment equal to what it would cost to have it fixed, if he refuses to do the work.
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