What is a rock clause?

Nobody knows for certain what's under the lawn until the bucket finds out. Rock that requires hammering, ripping, or blasting can multiply excavation cost, and a fixed price that silently includes that risk is a gamble one side always loses.

What a working rock clause says

• Definition: what counts as rock, typically material that can't be excavated with the equipment on site (for example, a specific class of excavator) and requires hammering, ripping, or blasting. Boulders over a stated size count too.
• Price: a unit rate per cubic yard or per hour of hammer time, agreed before the job starts.
• Notice: the contractor notifies the customer when rock is hit, documents it, and gets sign-off before the meter runs.

Document the hit

Photos of the rock in the trench, the hammer on the machine, and the pile of shot rock, all dated and located, turn a rock claim from an argument into an invoice line. The same goes for water, unsuitable soil, and buried debris: exclude, price, notify, document.