San Mateo County, CA Swimming Pools & Spas: Pool Permits (2026)

Pool and spa construction in unincorporated San Mateo County is regulated by the Building Code, zoning setbacks, and state pool safety statutes. A building permit is required for all in-ground pools/spas and for above-ground pools deeper than 18 inches. Plan submissions must include a site plan showing setbacks (typically 5 ft side/rear, 10+ ft front), drainage routing, pool barrier details, electrical bonding/grounding per CEC Article 680, and backflow prevention for water supply. Title 24 Chapter 31 requires a 60-inch minimum barrier around any pool over 18 inches deep with self-closing, self-latching gates. Health & Safety Code §115922 mandates at least one additional drowning-prevention feature from the 7-item list (safety cover, alarms on doors/windows exiting to pool area, self-closing doors on exits from home, removable mesh fencing, etc.). A property survey may be required when setbacks are tight or records are unclear. The Coastal Zone triggers an additional CDP. Inspections required: excavation, pre-gunite, electrical rough, plumbing/gas, barrier, and final.