San Luis Obispo County, CA Accessory Structures: Tiny Homes (2026)

Chapter 19.03 modifies the California Residential Code for unincorporated county construction. Among the appendices it adopts, Section 19.03.020(2) adds Appendix BB - Tiny Houses, and amends Appendix BB Section 101.1 so its scope covers only 'tiny houses used as single dwelling units,' which 'shall comply with this code except as otherwise stated in this appendix.' The amendment explicitly excludes park models and other recreational vehicles from being treated as a habitable dwelling unit under the appendix, so a tiny house on a trailer chassis marketed as an RV does not qualify; the structure must be built and permitted as a single dwelling unit to use the appendix's standards.

Because the appendix classifies a compliant tiny house as a dwelling, the ordinary permit and inspection rules for residential construction apply: an application must be filed with the building official and a permit obtained before construction begins under Section 19.02.020(b), amending Section 105.1, and the same title treats the finished tiny house as an R-3 occupancy, so its signed Final Inspection entry serves as the certificate of occupancy under Section 19.02.020(y), amending CRC Section R110.1. The same 19.03.020 modification list also adopts Appendix B (Patio Covers) and Appendix CI (Swimming Pool Safety Act) for the same residential permitting chapter, showing the tiny house appendix was added as one of several optional residential construction standards the county chose to bring into its amended Residential Code rather than leave unaddressed.