Accessory dwelling units (or “granny units,” “in-law units,” and various other names) are smaller units built on the same property as, or attached to, an existing primary residence. The County of San Mateo regulates the production of second units in the unincorporated areas of the County only (those areas that are not in the jurisdiction of incorporated cities). Find the regulating ordinance linked below.
Non-Coastal Zone
Coastal Zone
- Chapter 22.5.1. Accessory Dwelling Unit Regulations
- LCP Map 3.2 ADU Special Parking El Granada-Pillar Point
- LCP Map 3.1 ADU Special Parking Moss Beach-Montara
How to Apply
Resources:
- Second Unit Resource Center
- Symbium - 3rd Party tool to assess the feasibility of second unit construction on any property.