Hand-vetted contractors for whole-home renovations, additions, kitchens, baths, and ADUs across Lower North, Country Club Manor, Hillsborough Oaks, and the Carolands area. Matched by a team that works the Peninsula.
Hillsborough is an exclusively residential, estate-scale town, and that shapes almost everything we see here. The Lower North flats west of El Camino hold majestic 1910s-1930s estates (Beaux Arts and period revivals) on half-acre to 2-acre parcels, some with fairway views toward the Burlingame Country Club. Country Club Manor brings a 1950s pocket of four- and five-bedroom single-story homes blending Cape Cod and mid-century California ranch styling, while Hillsborough Oaks and Fagan Estates carry 1920s-1930s storybook architecture along Baileyana, Jackling, and Fagan Drive. The Carolands and Uplands area is home to the town's landmark estates, including the Carolands Chateau and the c. 1914 Beaux Arts La Dolphine on Manor Drive.
The town's design code sets a minimum house size of 2,500 square feet and caps floor area at a 25% Floor Area Ratio, so renovations here skew toward whole-home and addition scope rather than cosmetic refreshes. Our matchmakers work the Peninsula and place contractors on the kind of estate-scale projects Hillsborough demands: down-to-studs renovations on period homes, primary-suite and second-story additions that clear design review, detached ADUs on large lots, and gut kitchens finished to estate-level expectations.
Realistic 2026 cost ranges based on the projects our contractors are actually pricing in Hillsborough right now.
Hillsborough kitchens are typically full-scope gut remodels finished to estate-level expectations. On period-revival homes the work often means reconfiguring a once-formal service kitchen into an open family space, then layering in custom cabinetry, stone counters, and high-end appliances. Finish standards here run well above a standard Peninsula remodel, which is what drives the upper end of the range.
Primary baths on Hillsborough estates are full gut projects: expanded footprints, curbless walk-in showers, freestanding tubs, double vanities, and heated stone floors. Older 1910s-1930s homes frequently need plumbing and electrical rerun behind the walls before any finish work begins. Secondary and guest baths fall toward the lower end of the range.
Hillsborough overhauled its ADU ordinance (HMC Chapter 17.52) in late 2024 after a state compliance finding, establishing State Exempt, ADU Planning Permit, and discretionary Exception pathways. Detached ADUs are allowed up to 16 feet and attached up to 25 feet, with height limits waived for conversions of existing space. On large estate lots, detached units and pool houses are the most common builds, and Peninsula site conditions push pricing to the high end of Bay Area ADU costs.
Browse ADU models →This is the dominant project type in Hillsborough. Estate-scale renovations and rebuilds on half-acre to 2-acre parcels routinely run well into seven figures once you account for period-home structural work, design review, and estate finishes. We've matched contractors for full down-to-studs renovations, large additions, and second stories where the homeowner rebuilt every system alongside the cosmetic scope.
See how pricing works →Permits run through the Town of Hillsborough Building & Planning Department at 1600 Floribunda Avenue. The town does not publish a single plan-check timeline, so applicants should call the Building Division at (650) 375-7411 for case-specific timing, with plan-check inquiries directed to plancheck@hillsborough.net. The Planning Division at (650) 375-7422 handles design-review intake, and most estate-scale projects realistically run a year-plus from design through construction.
The Architecture and Design Review Board, a five-member volunteer board appointed by the City Council, holds public hearings on the design of new houses, additions, landscaping, street-facing fencing and gates, and other exterior changes, measured against the town's adopted Residential Design Guidelines. ADRB review is triggered by additions over 500 square feet and any second-story addition visible from the public right-of-way. The board meets the first Monday of each month at Town Hall, and its stated purpose includes maintaining and enhancing the historic quality of the town.
Parts of Hillsborough carry High or Very High Fire Hazard Severity Zone designations within the Local Responsibility Area. New construction and teardowns in the Wildland-Urban Interface or a High FHSZ must use fire-resistant construction methods and maintain defensible space, though Cal Fire's 2025 map update reduced the town's very-high acreage relative to the 2009 maps. Per-parcel status varies, so a specific lot should be checked on the OSFM FHSZ viewer. The San Andreas Fault runs immediately west of town along the Crystal Springs valley, and on older estate homes foundation bolting, cripple-wall shear paneling, and (on hillside parcels) drilled-pier upgrades are common adders during a major remodel.
Tell us about your project. A matchmaker will call you within one business day and hand-pick 2–5 contractors from our vetted network who have worked in Hillsborough before.
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