Concrete driveways

A driveway is the largest single slab most homes ever get, and it carries the most weight. We pour residential driveways at four inches over a compacted granular base, and go to five or six where a truck, trailer or RV will sit. Reinforcement is wire mesh or #4 rebar on chairs depending on the span and the subgrade, and it is tied and lifted rather than laid flat, because steel pulled to the bottom of a slab does nothing.

The part that decides whether a driveway lasts is jointing. Control joints go in at roughly two and a half times the slab thickness in feet — about ten feet apart on a four inch pour — and they are cut early, before the concrete decides where to crack on its own. Along the Wasatch Front that matters more than it does almost anywhere else: this valley runs through well over a hundred freeze-thaw cycles a year, and water sitting in an uncontrolled crack is what turns a hairline into a trip hazard.