Site Work, Excavation and Foundations
Site work sets the tolerances for everything after it. Begin with protection and control: silt fence and a stabilized entrance, tree protection, a benchmark, and Dig Safe notification before excavating. Disturbing an acre or more triggers a Stormwater Pollution Prevention Plan under the federal construction general permit. Work in or near wetlands triggers the Massachusetts Wetlands Protection Act: a 100-foot buffer zone to Bordering Vegetated Wetlands and a 200-foot riverfront area, with a Notice of Intent to the conservation commission and an Order of Conditions before you dig.
Excavation: strip and stockpile topsoil; keep spoil and equipment at least 2 ft back from the trench edge; a competent person classifies soil and inspects daily; at 5 ft depth, or any depth in unstable soil, a protective system (sloping, shoring, shielding) is required. Massachusetts also requires a trench permit at 5 ft and deeper.
Foundations: bearing strata must be firm and uniform; footings go below frost - in Massachusetts expect roughly 42 to 48 in of cover depending on locality, verified with the building official. Presume 1,500 psf soil bearing unless a soils report says otherwise. Step footings on slopes, keep them level, and dowel them. Backfill in compacted lifts and get the footing, foundation and waterproofing/drainage inspections before covering.
Rule of thumb: grade must fall at least 6 in within the first 10 ft away from the foundation, with a positive discharge point - never onto a neighbor's lot.