Guide
Converting a structure with one or two dwelling units to one with three or more units can trigger additional building code requirements.
Commercial Building Permit requirement
Upgrading from a house or duplex to three or more units could require a Commercial building permit, and your project must follow the commercial building code, which has different requirements than the residential code.
Commercial building code requirements include details such as:
- Sprinkler systems
- Increased fire rating of exterior walls based on distance from the property line
- Window and door opening limitations based on the property line
NOTE: Applicants can seek relief or alternatives to these requirements through a building code appeal process.
Seismic Upgrade Required
Change of occupancy from a house or duplex to 3 or more units will trigger a seismic upgrade under City Code Chapter 24.85 (i.e. change of occupancy from R-3 occupancy to R-1 or R-2).