Dirtworks Construction, LLC

Excavation contractors dig and move earth for foundations, basements, utilities, pools and site cuts. Most residential jobs run on a mini or mid-size excavator paired with a skid steer and a dump truck; larger cuts bring in a dozer or scraper. The price depends less on the size of the hole than on what is in the ground: clay, ledge rock, high groundwater and buried utilities all slow the machine down and change the hauling math. Before the bucket touches dirt the site needs an 811 utility locate, and any trench deeper than five feet needs a protective system under OSHA rules.

Paving preparation is the earthwork under asphalt or concrete: cutting the subgrade to plan, undercutting and replacing soft spots, placing and compacting aggregate base in lifts, and proof rolling with a loaded truck to find anything that pumps before the paving crew shows up. Asphalt is only as good as what is under it, and most premature cracking and rutting traces back to a thin or poorly compacted base rather than the mix. Base thickness runs from about four to six inches of crushed stone under a residential driveway to eight to twelve inches or more under a commercial lot or a road, compacted to 95 percent or better of maximum density, with the surface held to within a fraction of an inch of grade so the asphalt lift is uniform. Prep contractors often also handle the curb subgrade, drainage structures and the connection to existing pavement.

Retaining walls hold back soil where a grade change is too steep to slope, and they fail for one reason far more than any other: water. A wall that lasts has a compacted crushed-stone base, a perforated drain pipe at the heel, clean gravel backfill behind the wall face, and geogrid layers tied into the backfill on anything tall. Segmental concrete block is the most common residential system and can be built by a landscape contractor up to about four feet; above that, or wherever a driveway, slope or structure sits above the wall, an engineer's design is required by most codes and the wall becomes structural work. Poured concrete and reinforced masonry walls are used for tall cuts and tight sites, boulder walls for rural and natural-look projects, and pressure-treated timber for budget walls with a shorter life.