San Luis Obispo County, CA Outdoor Lighting: Billboard Lighting (2026)

20 requires a sign permit for any sign under Sec. 040 unless the sign is exempt under Subsection B, but Subsection C lists categories of signs that are prohibited outright regardless of permit. 6 singles out billboards: any permanent freestanding or building-attached advertising structure built of steel, concrete or wood, located adjacent to an Interstate or State highway, that leases or rents its advertising space to a party other than the operator of the structure, cannot be built anywhere in the unincorporated county. Because the structure itself is banned, the county never wrote a billboard-specific illumination rule; the general sign lighting standard at Sec.

070(B), requiring signs to be indirectly lighted by continuous, stationary, shielded fixtures directed solely at the sign or built internal to it, applies only to the sign types the code actually allows, such as wall, monument, freeway identification and freestanding signs approved under Sec. 060. A billboard erected before the 2020 sign code overhaul (Ord. 3420) that no longer conforms is treated as a nonconforming sign under Sec. 080, which cross-references Sec. 070 for the county's nonconforming-sign procedures rather than a lighting retrofit path.