Building permits, zoning, septic and RV rules in San Bernardino County, California

Yes for most structures. Unincorporated San Bernardino County requires a permit for any new detached residential or non-residential building over 120 square feet, plus tenant improvements, solar, patio covers, additions, pools, carports, fences over 6 feet, retaining walls over 3 feet, re-roofing, grading, demolition and more¹. A one-story detached shed, tool room or playhouse at 120 square feet or less can be exempt, but only if it has no utilities, meets minimum setbacks and stays under 14 feet tall¹. Structures that already stood before 1946 may carry an exemption under County Ordinance 574, but that exemption disappears the moment the structure is deemed unsafe or is altered, added to, or has a change of occupancy¹. Inside Rialto, Chino Hills and the Town of Apple Valley, the city or town issues its own building permits, so the county's rules here cover unincorporated land only^4,5,6. California law backs this up statewide: no building may be erected, altered or moved without a permit first obtained from the local building official, and every county building department must enforce the State Building Standards Code^13,14. California's owner-builder exemption still applies, but it only changes who can do the work, not whether San Bernardino County requires the permit itself¹⁰.

Building permits for unincorporated San Bernardino County go through Land Use Services' Building and Safety Division, based at the County Government Center, 385 N. Arrowhead Ave., First Floor, San Bernardino, CA 92415-0187¹⁵. Reach Land Use Services at (909) 387-8311; the same government center houses Land Development and Planning/Mining, so one call point covers most of a build¹⁵. Permit applications submitted after January 1, 2026 must comply with the 2025 California Building Standards Code; the application date filed with Building and Safety controls which code edition applies¹⁶. Building and Safety enforces the county's adopted standards through plan review, permit issuance, inspections, final approval and the Certificate of Occupancy¹⁶. Fees changed as of 2026 and are split into Plan Review and Building Permit components, plus any school, traffic or drainage fees that apply to a specific project, so get a project-specific quote from the office before budgeting¹⁷.

Yes. San Bernardino County regulates every unincorporated parcel through its Development Code, and each property sits in a zone or land use district with its own uses and standards². Inside Victorville¹⁸, Rialto¹⁹, Hesperia²⁰, Chino²¹, Chino Hills²², Apple Valley²³, Montclair²⁴, Twentynine Palms²⁵, Barstow²⁶, Grand Terrace²⁷ and Big Bear Lake²⁸, the city's own zoning applies instead.

Minimum parcel size matters when you split land: AG and FW districts require 10 acres and RC requires 40 acres², while RL requires 2.5 acres⁸. Map suffixes can change those minimums. Setbacks also vary by district: in the Valley Region, AG, RC and OS lots have a 25-foot front setback and FW has 75 feet, with 15 feet at the side and rear²⁹. In the Mountain Region, RC, FW and OS use a 25-foot front and 15-foot side and rear setbacks⁸. The county directs applicants to Land Use Services for the exact line on a parcel³⁰. Ag accessory structures can skip a planning permit at the listed sizes but still need a building permit⁸.

Environmental Health Services is the lead agency for reviewing onsite wastewater treatment systems (septic) in unincorporated San Bernardino County, and a building permit from Land Use Services is required before a new or replacement system is installed^3,9,31. The county program does not cover the incorporated cities and towns; Hesperia and Chino describe septic as a city matter inside their limits^9,32,33. California's statewide policy lets local agencies run their own program, which is how the county's version works³⁴.

A septic system is approved only where public sewer is unavailable, soils meet onsite standards, and the lot has room for a 100% expansion area³. New development must connect to sewer when the nearest property line is within 200 feet of an available sewer line³. Only about 14.5% of the county's soils are free of severe limits for a conventional drain field, so budget for a site evaluation and possibly an engineered system¹². Inspections are more likely in mountain regions, on slopes over 20%, or on parcels under 2.5 acres served by a well³. Any well needs a county well permit³⁵. Sewage holding tanks need Environmental Health Services approval and an annual operating permit⁹.

Not as a general matter. San Bernardino County's Development Code makes it unlawful to place, use or occupy any vehicle on a parcel for camping, dwelling or residency unless that use is authorized⁸. The ordinary landowner's exception: recreational camping in your own RV for up to 4 days within any 30-day period, only in the RC, AG, or RL-5-acre-or-larger districts⁸. Temporary living quarters in a manufactured home or travel trailer while you build may be permitted if the permit for the permanent home has already been obtained⁸. Temporary structures face the same rule: no camping or dwelling use without a Temporary Use Permit, Special Event Permit or other approval⁸. Seasonal labor quarters need a Site Plan Permit and Special Use Permit⁸.

A tiny home may be permitted if it meets the California Residential Code or the county's manufactured-home standards, and the county will not approve an RV for occupancy as a dwelling under that route⁸. A manufactured home may go on private land zoned RS, RL, RC, SD-RES or CR, needs a building permit before setup or site work, and outside a licensed park generally cannot be permitted if more than 10 years passed between manufacture and permit application³⁶. Short-term rentals in the Mountain and Desert Regions need a Short-Term Rental Permit, and RVs and travel trailers are not eligible rental units³⁷. Confirm what a parcel's zone allows with Planning before you buy¹⁵.

First, confirm the parcel's zone district, minimum lot size and whether a subdivision or road-access issue applies with Land Use Services Planning before you buy^2,15. Second, if there is no sewer, get a septic site evaluation from Environmental Health Services, since much of the county's soil needs an engineered system^9,12. Third, confirm your road is legal access: San Bernardino County only recognizes a road as legal access if it has a dedicated right-of-way to the county and public, or a public-use easement, and road dedication or paving can be required as a permit condition³⁸. Fourth, if the parcel sits in a County Floodplain Overlay or Floodplain Safety Review Area, no structure may be built, altered or converted there without full compliance with the county's floodplain chapter⁸. Fifth, apply for the building permit through Building and Safety, budgeting separately for Plan Review and Building Permit fee components^15,17. Sixth, if you're an owner-builder, remember the county caps for-sale, licensed-subcontractor structures at 4 a year, and a principal-residence exemption at 2 uses within any three-year period¹¹. Seventh, complete inspections in sequence and clear Building and Safety, Planning, Land Development, Public Works Roads and Fire Department sign-off before the county issues your Certificate of Occupancy¹.

This is a desert and mountain county more than a green one: only 4.1% of the land is wooded, average precipitation is about 6.6 inches a year, and severe drought hits roughly 39% of years¹². Terrain is gentler than the numbers might suggest, with 66% of the land at a 15% slope or less, but federal land covers a huge 87% of the county, which limits where private parcels sit and what borders them¹². If you're buying a larger tract with an eye toward splitting it, California's Subdivision Map Act and the county's own Development Code require a Tentative Map first, then a Parcel Map for four or fewer resulting parcels or a Final Map for five or more, plus whatever minimum lot size and improvement conditions apply to that zone^8,39. Prices reflect the mix of desert and mountain terrain: the typical home value is about $553,855, farmland runs around $47,339 an acre, and a typical home insurance premium is about $1,376 a year¹². The effective property tax rate runs about 0.7%, with a median property tax bill near $3,346 a year¹².