Excavation is priced in cubic yards, so you’ll need to find the volume of the area in order to calculate costs. Multiply the length, width, and proposed depth of your excavation site, then convert it into yards to get the volume. Multiply this figure by the price per cubic yard.

Most homeowners can measure by hand to get a rough estimate, even if it’s tedious. You may want to pull out a tape measure or use a string to help mark the area.

Because decomposed granite is a durable material, a crushed rock or gravel base is optional as long as the DG is properly installed and compacted. However, installing a base is a good idea because it will ensure proper drainage and stability and act as a weed suppressant (although you may still occasionally have to pull weeds). Installing an adequate base can also increase the durability of driveways and walkways. If you forego the paver base or gravel underneath, line the area with landscaping fabric to avoid weeds.

A perc test can take anywhere from one to eight hours to complete. The total time depends on factors like the amount of excavation required, the depth and width of the holes, and whether multiple test holes are needed. For a single hole, the process of filling it with water and monitoring the drainage rate usually takes less than an hour. Professionals can often complete the entire test in a single day. While it's possible to get results the same day, some companies may take a few days to provide the official report.

The average cost of excavation is approximately $3,200, with typical projects ranging from $500 to $15,000. Depending on the contractor, you may be charged between $50 and $200 per cubic yard or an hourly rate of $40 to $180 for an excavation specialist. The total cost is influenced by several factors, including the project size, the amount of soil to be removed, and the soil's condition. Hard soil, tree roots, or excessive rocks and clay can increase the price, potentially adding $200 to $1,200 to the final bill. Other factors that can drive up costs include the presence of nearby structures that complicate the work or tight spaces that require manual excavation instead of heavy machinery.