StoneBase Masonry - Basement & Foundation repair specialist Boston

Massachusetts has no foundation-contractor license, but the contractor must hold Home Improvement Contractor (HIC) registration, and structural work needs a Construction Supervisor License (CSL) plus a building permit from the City of Boston Inspectional Services Department. Significant structural repair, underpinning a rubble wall, installing piers, or rebuilding a section, requires drawings stamped by a registered Professional Engineer. Exterior changes in Back Bay, Beacon Hill, and other Boston Landmarks districts need commission review. Any exterior excavation or regrading near the Charles, Neponset, or coastal wetlands can fall under Conservation Commission jurisdiction through the Wetlands Protection Act.

Foundation costs in Boston run high because of tight access, debris hauling, and city labor rates. Sealing a single crack with epoxy or polyurethane injection typically runs $400-$900. A full interior perimeter French drain with a sump pump lands around $8,000-$20,000 depending on linear feet, and a basement under a triple-decker pushes the top of that band. A standalone sump pump install is usually $1,200-$3,000, more with battery backup. Stabilizing a bowing rubble or brick wall with carbon-fiber straps or steel beams runs $5,000-$12,000, and exterior excavation with membrane waterproofing starts around $15,000 and climbs.

Massachusetts requires a written contract and a Home Improvement Contractor registration for most residential foundation repair & waterproofing work; ask for the registration number and check it before paying a deposit.

More on permits, costs, rebates and common questions, plus every other foundation repair & waterproofing contractor serving the town, on the Foundation Repair / Waterproofing in Boston page.