Off-grid site report
San Luis Obispo County, CA
35.2828, -120.6596 · 240 ft elevationRead this before you act on anything below. This is my researched starting point for San Luis Obispo County, CA, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
The local rulesSan Luis Obispo County, CA
Zoning & raw-land occupancy
RestrictedUnincorporated county land is governed by Title 22 (inland) and Title 23 (coastal) of the County Code; camping or occupying raw land outside permitted uses is restricted, and RV parks require a discretionary use permit with public hearings. source
Dwellings, tiny homes & RVs
RestrictedCounty Code Enforcement says you may store an RV on a residential lot but cannot live in it; RV living is only allowed in a state-approved RV or mobile home park. The City of San Luis Obispo separately allows small owner-occupied tiny homes, but that's a city rule only. source
Building permits & codes
RestrictedThe County Planning & Building Department administers Title 19, requiring permits and inspections under the state Building Standards Code, with no general off-grid exemption. source
Septic & composting toilets
RestrictedThe county runs a Local Agency Management Program for onsite wastewater systems, adopted by the Regional Water Board and Board of Supervisors and folded into Title 19, setting technical standards and requiring operating permits for alternative systems; composting toilets are not confirmed as a distinct permitted option. source
Greywater reuse
Unclear - verifyNo county-specific greywater ordinance was confirmed beyond the state Plumbing Code baseline; ask Environmental Health Services or Planning & Building to confirm any local variation. source
Rainwater harvesting
Generally allowedRainwater harvesting follows state law, and the county's stormwater guidance includes it as a credit tool in its Low Impact Development handbook; no added county permit was confirmed for basic rooftop catchment. source
Private wells & water rights
RestrictedSLO County Environmental Health Services is the state-designated well permitting authority and requires a licensed C-57 contractor; the Paso Robles Groundwater Basin has additional drilling restrictions under a county urgency ordinance. source
Living disconnected from utilities
Unclear - verifyThere's no dedicated county ordinance on off-grid utility disconnection, but RV-occupancy enforcement and septic/well permitting act as practical barriers to fully disconnected permanent living outside an approved structure. source
Sun30-year normals
- Peak-sun hours, annual average
- 6.2 hrs/day
- Worst month (sizes an off-grid array)
- 4.3 hrs/day
- Yearly output per 1 kW of panels
- 1,739 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 23 in/yr
- Snowfall
- 0 in/yr
- Heating degree days
- 2,488 (mild)
- Frost-free season
- Jan 9 to Dec 20
How far help isstraight-line
- Hospital
French Hospital - 0.6 mi
- Fire station
SLO City Fire Station #1 - 0.9 mi
- Hardware store
Harbor Freight Tools - 1.0 mi
- Grocery
Smart & Final Extra! - 0.2 mi
From OpenStreetMap. Road miles will be longer, often much longer in hill country.
Plan this spot
These open with this location's real numbers already filled in (ZIP 93403).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in San Luis Obispo County, CA?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 22, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.
New here, or not sure where this fits? Start here walks through the whole thing in order.