Yolo County, CA Building Permits, Zoning & Septic Rules

Unincorporated Yolo County, California requires a building permit from Yolo County Building Inspection Services before you build, move or alter any structure, and the county zones all unincorporated land¹². Both offices, and Environmental Health, which permits septic systems and wells, work out of 292 West Beamer Street in Woodland³⁴. Soils rarely suit a standard septic field, so expect a site evaluation with soil pits⁵⁶.

At a glance

Building permit: Required from Yolo County Building Inspection Services in unincorporated areas¹⁷
Zoning: Yes; county zoning (Title 8) covers all unincorporated land, and cities zone their own²⁸
Septic: Yolo County Environmental Health; starts with a site evaluation by a qualified professional⁹⁶
Wells: Environmental Health permit required; new agricultural wells in groundwater focus areas faced a moratorium¹⁰
Farm buildings: Permit-exempt ag buildings allowed in A-N and A-X zones if all conditions are met¹¹
Owner-builder: Allowed under state law; you still need the building permit¹²¹³
RV living: State default limits RV living to parks unless a local ordinance allows it; county rule unconfirmed¹⁴

Who to call

Building permits

Yolo County Building Inspection Services (Department of Community Services)

Building, grading, pool, flood hazard development and county fire permits in unincorporated Yolo County

530-666-8037

[email protected]

292 West Beamer Street, Woodland, California 95695

Online permits →

Building permits

Yolo County Building Inspection Services: permit requirements and fees

What needs a permit and how fees are charged

Floodplain permits

Yolo County Building Inspection Services: Flood Protection

Floodplain development rules, flood zone determinations and elevation certificates

Planning & zoning

Yolo County Planning Division (Department of Community Services)

Zoning, land divisions and land-use permits in unincorporated Yolo County

(530) 666-8775

292 West Beamer Street, Woodland, CA 95695

Septic permits

Yolo County Environmental Health Division, Land Use Protection Unit

Septic (OWTS) permits, water well permits, small public water systems

(530) 666-8646

[email protected]

292 W. Beamer Street, Woodland, CA 95695

Septic permits

Yolo County Environmental Health: Onsite Wastewater Treatment System (septic) Program

Septic design, installation and repair permits

Septic permits

Yolo County Environmental Health: septic site evaluations

Site evaluation process for new septic systems

Well permits

Yolo County Environmental Health: Water Well Program

Well construction, modification and abandonment permits; agricultural well moratorium updates

Roads & driveways

Yolo County Public Works Division: encroachment permits

Encroachment permits for driveways and other work in county road right-of-way

[email protected]

Contact details are copied from each office’s official page and were checked against it on September 24, 2026.

Do you need a building permit in Yolo County, California?

Yes. In unincorporated Yolo County, any owner or agent must get a permit from Yolo County Building Inspection Services before constructing, enlarging, altering, moving or demolishing a structure¹. That covers electrical, gas, mechanical and plumbing work too, and grading needs its own permit from the building official⁷. The 2025 California Building Standards Code applies to permit applications dated on or after January 1, 2026¹⁵.

Farmers get one real exemption. An agricultural building that houses farm implements, hay, grain, livestock or horticultural products needs no building permit in the A-N or A-X zones, if it is not lived in, not used for processing or packing, not open to the public, and meets zoning setbacks and the code's height and area limits¹¹. Plumbing and electrical work in that building still need separate permits¹¹. Most plan review and inspection fees are based on the valuation of the work, and new homes also pay school fees directly to the school district⁷.

Who is the Yolo County building department, and how do you reach them?

Yolo County Building Inspection Services, part of the Department of Community Services, is at 292 West Beamer Street in Woodland; call 530-666-8037 or email [email protected]³. Applications go through the county's Yolo Builds online permit portal³. The Planning Division, (530) 666-8775, and Environmental Health, (530) 666-8646, are in the same building, so one trip can cover zoning, septic and building questions¹⁶⁴.

Fire permits depend on where you are. The Davis, East Davis, Springlake, West Sacramento, Winters and Woodland fire districts issue their own; in every other fire district, fire permit applications go to the Department of Community Services⁷. Land inside Davis, Woodland, Winters or West Sacramento city limits is outside the county's zoning, so check the city's own rules².

Does Yolo County have zoning?

Yes. Yolo County zones all of its unincorporated land, and cities administer their own zoning². The rules are in Title 8 of the county code, which holds the zoning regulations, the subdivision regulations used by Public Works, and the Flood Protection Regulations⁸. Title 8 does not tell you your parcel's zone; the Planning Division's GIS map does, and a planner will meet with you by appointment⁸¹⁶.

Much of rural Yolo is zoned agricultural, and the A-N and A-X zones are where the permit-exempt farm building rule applies¹¹. Our research did not confirm a county minimum home size or a lot-coverage limit; ask the Planning Division about your zone's standards¹⁷. Splitting land falls under the state Subdivision Map Act, and the county can add its own requirements for roads, drainage, sanitation and water¹⁸.

How do septic permits work in Yolo County?

Yolo County Environmental Health regulates septic systems wherever a community sewer connection is not available, and you need its installation permit before work starts⁹¹⁹. A new septic installation permit requires a building permit¹⁹.

Every design starts with a site evaluation²⁰. You hire a septic qualified professional, submit the request form and fee to Environmental Health, and schedule the evaluation at least 48 hours ahead⁶. At least two pits are dug to at least eight feet: one in the primary septic area and one in the replacement area⁶.

Expect an engineered system. The NRCS rates only 2.5% of Yolo County's soils free of severe limits for a conventional drain field⁵. An alternative system adds engineering to deal with a high water table, tight soil or rock, and alternative systems may need annual operating permits²⁰¹⁹. A property owner may do some septic installations and repairs in Yolo County²⁰. In developed areas, a parcel less than 200 feet from a sewer collector must get sewer service²¹.

Can you live in an RV or tiny home on your land in Yolo County?

Not by default. California treats RVs as temporary housing, and unless a local ordinance allows otherwise, living in one is generally limited to mobilehome parks or special occupancy parks¹⁴. We could not confirm Yolo County's own rule for camping or living in an RV on private land, so ask the Planning Division before you buy¹⁶.

A tiny home is legal to live in only if it is approved as one of the recognized types (a HUD-code manufactured home, a California Residential Code home, factory-built housing, an RV, a park trailer or a camping cabin) and sits where that type is allowed²². A tiny home that fits none of those is a noncomplying structure, and living in it is illegal²². A new manufactured home must be at least 320 square feet²³. An accessory dwelling unit is approved ministerially, with no hearing, and the county must say within 15 business days whether your application is complete²⁴.

What are the steps to build a home in unincorporated Yolo County?

Look up your parcel's zoning on the county GIS map and book a planner appointment at (530) 666-8775¹⁶.
Check the flood zone; in zones A, AE or AO, any development needs a flood hazard development permit⁷.
Hire a septic qualified professional and schedule the site evaluation with Environmental Health⁶.
Get a well permit from Environmental Health if you need a well, and meet its well requirements for building projects¹⁰.
Get an encroachment permit from Public Works for a driveway onto a county road²⁵.
Apply for the building permit through Yolo Builds; the septic installation permit also requires it³¹⁹.
Pay plan review fees first and permit fees once the plans are approved, plus school fees paid directly to your school district⁷.
Pass inspections, including the well final inspection, before you move in¹⁰.

What should you check before you buy land in Yolo County?

Water comes first. Yolo County has had severe drought in 42.2% of years, and rain averages 21.4 inches a year²⁶²⁷. Every new well needs an Environmental Health permit, and the county has restricted new agricultural wells in groundwater focus areas, so confirm the rules for your parcel before you pay for land¹⁰. Private well owners can use the county's free well testing program¹⁰.

Soils come next: order a septic site evaluation early, because only 2.5% of the county's soils suit a conventional drain field⁵. Check flood maps too, using the county's flood zone determination form²⁸. Heat matters: the county averages 62.2°F, and mid-century projections show about 39.7 days a year at or above 100°F²⁹³⁰.

Farmland averages about $10,780 an acre and a typical home about $624,608³¹³². The effective property tax rate is 0.8%, and the median bill is $4,567³³³⁴. The nearest metro area is about 20 miles away³⁵.

Watch-outs

Yolo County put a moratorium on new agricultural well permits in the Yolo Subbasin Groundwater Agency focus areas. The county's page says it would expire August 25, 2026 unless the Board extended it, and staff were to bring options that day, including a one-year extension¹⁰. Call Environmental Health for its current status¹⁰.
Only 2.5% of Yolo County's soils rate well for a conventional septic drain field, so budget for a site evaluation with two soil pits and possibly an engineered alternative system⁵⁶.
In flood zones A, AE and AO, even grading, filling, paving or storing materials needs a Yolo County flood hazard development permit⁷.
A permit-exempt agricultural building in the A-N or A-X zones cannot be lived in or used by the public, and its plumbing and electrical still need permits¹¹.
Yolo County's rules on living in an RV on private land were not confirmed; California's default limits RV living to parks unless a local ordinance says otherwise¹⁴.

Sources

Written September 24, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

How Yolo County scores

Seclusion17100% ev.

Self-Sufficiency4196% ev.

Admin Boringness40100% ev.

Durability36100% ev.

Property Autonomy56100% ev.

Carry Cost49100% ev.

Evidence strength: 99%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$625kTypical home

0.8%Property tax

$10,780Land / acre

21.4"Annual rain

42.2% of yrsSevere drought

39.7 / yr (+22)Mid-century 100°F days

97.2 daysMid-century dry spell

1.64" (+6.1%)Mid-century 1-day rain

1.07×Wildfire change factor

100%Forward climate coverage

$1,243Home insurance / yr

4.9% / yrInsurance growth

0.61%Nonrenewal rate

county median (2+ published ZIPs)Insurance basis

7,198,627People within 2 hr

148,865Radius comparison (15 mi)

217.3People / sq mi

8.2%Federal land

73.4%Land at 15% slope or less

2.5%Septic soil without severe limits

13,741 acWorkable land screen

20.2%Wooded land

17 tonsBiomass / forest ac

62.2°FAvg temp

Answers from the rulebook for Yolo County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Yolo County rules

County-wide zoningPresent (with conditions)
County zoning districts and land-use controls in the unincorporated portions of Yolo County.
- The source expressly limits this county zoning layer to unincorporated portions of the county.
- Incorporated municipalities may administer separate local zoning rules.
“Description: This is the zoning layer for the County of Yolo. It inlcudes only zoning for the unincorporated portions of the county.”
Layer: Zoning (ID: 2) ↗Re-checked Sep 24, 2026
Zoning districtsPublished
County zoning regulations and zoning-district materials for unincorporated Yolo County.
- Title 8 is the county zoning and land-development code; incorporated municipalities may administer their own zoning rules.
- The page identifies the county zoning regulations generally but does not provide parcel-specific zoning designation.
“Title 8 (approximately 363 pages of text) consists mainly of the County zoning regulations (Chapter 2 of Title 8). Title 8 also includes subdivision land development regulations used by Public Works (Chapter 1) and Flood Protection Regulations (Chapter 4).”
Land Development & Zoning Ordinance | Yolo County ↗Re-checked Sep 24, 2026
Who permits septicCounty
Onsite wastewater treatment systems and septic systems in Yolo County.
- The county Environmental Health program regulates OWTS where community sewer connection is unavailable.
“Onsite Wastewater Treatment System (OWTS) Program regulates OWTSs, or more commonly known as "Septic Systems".”
Land Use Programs | Yolo County ↗Re-checked Sep 24, 2026
Off-grid sanitationLimited
Onsite septic/OWTS sanitation where connection to a community sewer system is unavailable.
- Septic systems are the county-described onsite treatment option when community sewer is unavailable.
- Installation requires an approved Yolo County Environmental Health septic installation permit before work begins.
- A new septic installation permit requires a building permit.
- Alternative systems may require annual operating permits and service-provider reports.
“Septic systems are used to treat human sewage on a site where connection to a community sewer system is not available.”
Land Use Programs | Yolo County ↗Re-checked Sep 24, 2026
Mandatory utility hookupSewer (with conditions)
Developed areas subject to the Yolo County Improvement Standards where a legal parcel contains a source of sewage and is less than 200 feet from a sewer collector.
- The rule applies to developed areas and the parcel/property-line distance condition stated in the standards.
- The cited standard requires a sewer service to be provided; it does not establish a universal countywide connection rule for every parcel.
- Sewer service location and construction remain subject to the Improvement Standards and County Engineer requirements.
maximum property-line distance from collector: < 200 feet (applies to developed areas containing a source of sewage)
“In developed areas, a sewer service shall be provided to each legal parcel containing a source of sewage and having a property line less than 200 feet from a collector.”
Yolo County Improvement Standards, Section 7.0 Sewer ↗Re-checked Sep 24, 2026
Agricultural exemptionAvailable (with conditions)
Permit-exempt agricultural buildings in Yolo County A-N or A-X zones.
- The building must be an agricultural building used to house farm implements, hay, grain, poultry, livestock, or horticultural products; it cannot be a place of human habitation, employment where agricultural products are processed, treated, or packaged, or a place used by the public.
- The Director or designee must determine the building is in an A-N or A-X zone and complies with Title 8 zoning requirements, including setbacks and site plan approvals, and all applicable state and federal laws.
- The building must comply with Title 7 construction standards and California Building Code Appendix C Section C102 height and area limits.
- Plumbing and electrical work require separate permits; no mechanical permit is allowed within the exempt building.
- Written Fire Code Official compliance determination is required, including fire access and water supply.
- Additional flood-zone, sanitation, health, water-quality, parcel-boundary, and fire-separation conditions apply.
- The property owner or authorized agent must file a written application with the Chief Building Official, scaled plot plan, and written use/indemnity/successor agreement.
- The exemption exists only while the building remains an agricultural building; a full permit process is required for another use.
agricultural zoning: A-N or A-X · nonagricultural parcel separation: >= 60 feet (Building must be no closer than 60 feet from a parcel boundary not zoned agricultural)
“A building permit shall not be required for an agricultural building that satisfies all of the following conditions:”
Sec. 7-1.04. Amendments to the California Building Code ↗Re-checked Sep 24, 2026

California rules that apply here

Building permitRequired
Construction projects within the California Department of Health Care Access and Information Office of Statewide Hospital Planning and Development jurisdiction, including health-facility projects requiring HCAI review.
- Written plan approval must be issued before the building-permit application proceeds.
- The application must provide contractor information, Inspector of Record information, and a Testing Inspection and Observation program.
- The TIO program must be field-approved before approval and subsequent issuance of the building permit.
- This claim does not establish the permit rule for projects outside HCAI jurisdiction.
“Once a project receives written plan approval, a Building Permit application is submitted through the e-Services Portal.”
Building Permits & Construction Observation ↗Re-checked Sep 26, 2026
Owner-builder exemptionAvailable (with conditions)
Exemption from California contractor-licensing chapter for an owner-builder who builds or improves a structure on the owner’s property; this does not itself establish exemption from local building permits, inspections, or other code requirements.
- For work personally performed by the owner or performed by the owner’s employees, none of the improvements may be intended or offered for sale, and employee compensation must be wages as their sole compensation.
- For work directly contracted to licensed trade contractors, the owner must directly contract with licensees duly licensed for the respective trades.
- For single-family residential structures under the licensed-contractor arrangement, no more than four structures may be intended or offered for sale in a calendar year; this limitation does not apply if the owner contracts with a general contractor for construction.
- For a homeowner improving a principal residence or its appurtenances, the work must be performed before sale, the homeowner must have actually resided in the residence for the 12 months before completion, and the homeowner must not have used this exemption on more than two structures more than once during any three-year period.
- A nonprofit corporation may qualify when assisting an owner-builder participating in a mutual self-help housing program.
- Sale or offering for sale within one year after completion creates a rebuttable presumption that the structure was undertaken for sale; sale or offering for sale of five or more structures within one year creates a conclusive presumption.
- This is a contractor-licensing exemption and should not be treated as a building-permit exemption.
single-family structures intended or offered for sale: <= 4 structures per calendar year (Does not apply if the owner contracts with a general contractor for construction.) · prior residence occupancy: >= 12 months before completion (Applies to the principal-residence homeowner exemption.) · owner-builder exemption use: <= 2 structures during any three-year period (The statute states the homeowner has not availed himself or herself of the exemption on more than two structures more than once during any three-year period.) · sale presumption period: 1 year after completion (Sale or offering for sale creates a rebuttable presumption; five or more structures creates a conclusive presumption.) · conclusive-presumption threshold: >= 5 structures within one year after completion (Structures sold or offered for sale by the owner-builder.)
“This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
California Business and Professions Code Section 7044 ↗Re-checked Sep 26, 2026
3 more reviewed findings on this topic
- Conditional — Owner-builders performing or arranging construction work in California, including Yolo County.
  “(a) This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
  California Business and Professions Code section 7044 ↗Re-checked Sep 24, 2026
- Conditional — Owners who build or improve structures on their own property, and homeowners improving their principal residence or appurtenances, subject to Business and Professions Code section 7044.
  “(a) This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
  California Business and Professions Code Section 7044 ↗Re-checked Sep 26, 2026
- Available (with conditions) — California contractor-licensing requirements for an owner who builds or improves a structure on the owner’s property; this is not stated as an exemption from building permits, inspections, or other code requirements.
  “This chapter does not apply to any of the following: (1) An owner who builds or improves a structure on his or her property”
  California Business and Professions Code section 7044 ↗Re-checked Sep 26, 2026
Building code adoptedAdopted (with conditions)
California Building Standards Code, California Code of Regulations, Title 24, including the 2025 California Building Code and related parts, for buildings and structures subject to the state code.
- The 2025 California Building Standards Code applies to buildings and structures with a permit application date on or after January 1, 2026.
- The applicable local building department or enforcing agency determines how the permit application date is established in a specific jurisdiction.
- The code includes multiple parts, including the California Building Code, California Residential Code, Existing Building Code, Electrical Code, Mechanical Code, Plumbing Code, Energy Code, Wildland-Urban Interface Code, Fire Code, and Green Building Standards Code.
effective date: 2026-01-01 · permit application date: >= 2026-01-01
“The 2025 California Building Standards Code (CBSC), California Code of Regulations (CCR), title 24, will become effective on January 1, 2026, as a result of the 2024 Triennial Code Adoption Cycle. [...] The 2025 CBSC applies to all buildings and structures with a permit application date on or after January 1, 2026.”
Approved Building Standards ↗Re-checked Sep 9, 2026
One more reviewed finding on this topic
- Adopted — California statewide building standards, including residential construction subject to Title 24 of the California Code of Regulations.
  “Except as otherwise specifically provided by law, the building standards adopted and submitted by the department for approval [...] shall be adopted by reference”
  California Health and Safety Code Section 17922 ↗Re-checked Sep 26, 2026
InspectionsRequired
Construction projects within HCAI jurisdiction involving California health facilities.
- HCAI field personnel make periodic site visits.
- The Inspector of Record is responsible for continuous inspection of the work.
- The inspections address seismic, fire, life-safety, and other building-code requirements.
“The approved IOR with the required personal knowledge performs only those duties associated with the required continuous inspections”
HCAI Standard Project Process ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- Required — California owner-builder projects addressed by the Contractors State License Board guidance.
  “Your project must pass codes and building inspections.”
  Owner-Builder Responsibilities ↗Re-checked Sep 26, 2026
Certificate of occupancyRequired
Completed construction projects within HCAI jurisdiction involving California health facilities.
- The HCAI Compliance Officer issues the project-completion Substantial Compliance or Certificate of Occupancy once required conditions are met.
- The stated examples include delivery of all test reports to the Inspector of Record, clearance of outstanding items, and completion of the Testing, Inspection and Observation Program.
- Once construction is completed, the certificate of occupancy allows the owner to apply to the Department of Health Services for a license to operate the health facility.
“Issues the certificate of occupancy and/or construction final.”
HCAI Standard Project Process ↗Re-checked Sep 26, 2026
Minimum dwelling sizeSpecified
Efficiency units permitted by a California city, county, or city and county.
- The local jurisdiction must adopt an ordinance permitting the efficiency unit.
- Occupancy is limited to no more than two persons.
- The unit may have partial kitchen or bathroom facilities as specified by the local ordinance.
- All other applicable minimum standards under Health and Safety Code Part 1.5 continue to apply.
minimum floor area: >= 150 square feet · maximum occupancy: <= 2 persons
“Notwithstanding Sections 17922, 17958, and 17958.5, a city, county, or city and county may, by ordinance, permit efficiency units for occupancy by no more than two persons which have a minimum floor area of 150 square feet and which may also have partial kitchen or bathroom facilities, as specified by the ordinance.”
California Health and Safety Code Section 17958.1 ↗Re-checked Sep 9, 2026
SetbacksSpecified
Qualifying SB 9 housing developments in single-family residential zones, including development of up to two primary residential units, subject to the cited statutory eligibility requirements and local ministerial review.
- The parcel must be located in a single-family residential zone.
- The project must involve no more than two residential units.
- Objective standards may be applied only if they do not physically preclude the statutory housing objectives, subject to the stated exceptions.
- No setback may be required for an existing structure or a structure constructed in the same location and to the same dimensions as an existing structure.
- For SB 9 projects, side and rear setbacks may not exceed four feet; a local agency may apply a lesser setback, such as 0–4 feet.
- The local agency cannot apply existing side and rear setbacks applicable in the single-family residential zones.
- The four-foot side and rear setback standards are not subject to modification.
- The fact sheet cites Government Code Sections 65852.21(b)(2)(B) and 66411.7(c)(3).
maximum side setback: <= 4 feet (A local agency may choose to apply a lesser setback, including 0–4 feet.) · maximum rear setback: <= 4 feet (A local agency may choose to apply a lesser setback, including 0–4 feet.)
“SB 9 establishes an across-the-board maximum four-foot side and rear setbacks.”
SB 9 Fact Sheet ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- District specific (with conditions) — Building setbacks, side and rear yard requirements, and property line requirements under California's State Housing Law framework.
  “building setback, side and rear yard requirements, and property line requirements are hereby specifically and entirely reserved to the local jurisdictions”
  California Health and Safety Code Section 17922 ↗Re-checked Sep 26, 2026
Living in an RVTemporary only (with conditions)
Occupancy of recreational vehicles as residential units in California.
- RVs are not intended for occupancy as permanent dwellings.
- Unless a local ordinance allows otherwise, RV occupancy generally is limited to mobilehome parks or special occupancy parks governed by the Mobilehome Parks Act or Special Occupancy Parks Act.
- Applicable state or local approval and enforcement requirements depend on the RV's location and classification.
maximum gross area: <= 400 square feet (Measured at maximum horizontal projections; internal living room area must be less than 320 square feet excluding specified built-in equipment and bath/toilet rooms.)
“RVs are not intended for occupancy as a permanent dwelling. [...] Unless otherwise allowed by a local ordinance, RVs generally may be occupied only in mobilehome parks or special occupancy parks”
Information Bulletin 2016-01: Tiny Homes ↗Re-checked Sep 9, 2026
Camping on your landLimited
Camping in units operated by the California Department of Parks and Recreation statewide.
- Camping is confined to areas designated for that purpose.
- Occupancy by the same persons, equipment, or vehicles is generally limited to 30 days in any calendar year in that unit.
- The Department may establish shorter or longer occupancy limits.
- When a shorter seasonal limit applies, the camper must vacate the campsite and may not reregister in the unit until 48 hours have expired, measured from 12:00 noon on the checkout day to 12:00 noon on the second day following.
- A district superintendent may permit one-night camping in a day-use area or portion of one, subject to Department-established fees and vehicle limitations; occupants must vacate by 9:00 a.m. the following morning.
- California State Parks' current reservation policy states that each campground has a consecutive-night limit, requires a 48-hour absence after that limit, and generally has a 30-night annual maximum, subject to individual park policies.
general annual occupancy limit: 30 days per calendar year per unit (The Department may establish shorter or longer limits of occupancy.) · return interval after shorter seasonal limit: 48 hours (Measured from 12:00 noon of the checkout day to 12:00 noon of the second day following.) · one-night camping in day-use area: 1 night (Only if permitted by the district superintendent; occupants must vacate by 9:00 a.m. the following morning.)
“Occupancy by the same persons, equipment, or vehicles of any camping facility is limited to a total of 30 days in any calendar year in that unit.”
California Off-Highway Motor Vehicle Laws 2014 ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- Allowed (with conditions) — Temporary camping in California special occupancy parks, including parks containing recreational vehicles, tents, or camping cabins.
  ““Special occupancy park” means a recreational vehicle park, temporary recreational vehicle park, incidental camping area, or tent camp.”
  What is a Mobilehome Park or Special Occupancy Park? ↗Re-checked Sep 26, 2026
Tiny homesAllowed (with conditions)
Occupancy of a structure marketed or described as a tiny home in California.
- The tiny home must comply with applicable standards and be approved as a HUD-Code manufactured home, California Residential or Building Code home, factory-built housing, recreational vehicle, park trailer, or camping cabin.
- The location must be approved for the applicable classification.
- A tiny home that does not fit one of those classifications and does not comply with the California Building Standards Code is a noncomplying structure whose occupancy is illegal.
- Approving and enforcing agencies vary depending on whether the unit is inside or outside a mobilehome or special occupancy park.
park trailer or RV gross area limit: <= 400 square feet (Applicable classification-specific exclusions and standards apply.)
“In order to be occupied, a tiny home must comply with the standards of, and be approved as one of the following types of structures: a HUD-Code manufactured home (MH), California Residential Code or California Building Code home, factory-built housing (FBH), recreational vehicle (RV), park trailer (PT) or camping cabin (CC).”
Information Bulletin 2016-01: Tiny Homes ↗Re-checked Sep 9, 2026
Manufactured homesAllowed (with conditions)
Occupancy of manufactured homes inside or outside mobilehome parks in California.
- The manufactured home must satisfy applicable federal standards and California Manufactured Housing Act and Title 25 requirements.
- Installation and approval for occupancy are governed by the Mobilehome Parks Act.
- HCD or a local enforcement agency with assumed Mobilehome Parks Act authority is responsible for ensuring compliance with statutory construction and maintenance requirements.
- Local agency approvals may be necessary for the project.
minimum width for a new manufactured home: >= 8 body feet (The statutory definition also includes units at least 40 body feet in length.) · minimum erected floor area for a new manufactured home: >= 320 square feet
“MHs may be occupied outside or inside of mobilehome parks and installation and approval for occupancy is governed by the Mobilehome Parks Act (MPA), HSC Sections 18200, et seq., and Title 25, CCR Sections 1000, et seq.”
Information Bulletin 2016-01: Tiny Homes ↗Re-checked Sep 9, 2026
Accessory dwellingsAllowed (with conditions)
ADUs and junior ADUs subject to California State ADU Law.
- Approval is ministerial and without discretionary review or a hearing.
- Development standards must be objective and knowable in advance.
- The local permitting agency must determine application completeness and provide written notice within 15 business days.
- If an application is incomplete, the agency must identify missing items and explain how to complete it.
- Local site, building, health, safety, fire, utility, and other applicable requirements continue to apply.
written completeness determination: <= 15 business days (Measured from the permitting agency's receipt of the application.) · final written determination after appeal: <= 60 business days (Applies after receipt of the written appeal.)
“A permit application for an accessory dwelling unit shall be considered and approved ministerially without discretionary review or a hearing [...] A permitting agency shall determine whether an application to create or serve an accessory dwelling unit is complete and provide written notice of this determination to the applicant not later than 15 business days after the permitting agency received the application.”
Accessory Dwelling Unit Handbook March 2026 ↗Re-checked Sep 9, 2026
Septic permitLimited
New, replacement, and corrective-action OWTS in California; existing properly functioning systems may fall under Tier 0 rather than new/replacement permitting requirements.
- Tier 1 applies to qualifying new or replacement OWTS when no Regional Water Board-approved LAMP exists, with a maximum flow of 3,500 gallons per day.
- Tier 2 applies to qualifying new or replacement OWTS under an approved LAMP, with a maximum flow of 10,000 gallons per day.
- Tier 3 applies near impaired surface waters subject to a TMDL, a special LAMP provision, or within 600 feet of a water body listed on OWTS Policy Attachment 2; supplemental treatment may apply.
- Tier 4 applies to systems that are not properly functioning and require corrective action.
- Local agencies issue the permits and local LAMP requirements may differ from Tier 1.
Tier 1 maximum flow: <= 3500 gallons per day (Qualifying new or replacement OWTS without an approved LAMP.) · Tier 2 maximum flow: <= 10000 gallons per day (Qualifying new or replacement OWTS under an approved LAMP.) · Tier 3 water-body setback: <= 600 feet (Applies to a water body listed on OWTS Policy Attachment 2.)
“Tier 1 applies when a Local Agency Management Program (LAMP) has not been approved by the Regional Water Board. Maximum flow rate is 3,500 gpd.”
Onsite Waste Water Treatment Systems ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- Required — New and replacement onsite wastewater treatment systems (OWTS), commonly known as septic systems, statewide in California.
  “Every new or replacement septic system requires a permit, either through your local jurisdiction (City or County) OR from the Central Coast Water Board.”
  2023 OWTS Policy ↗Re-checked Sep 26, 2026
Septic inspectionLimited
OWTS in a Tier 3 Advanced Protection Management Program with supplemental treatment components, including systems in specified impaired-water-body areas statewide.
- The requirement applies to OWTS in an Advanced Protection Management Program with supplemental treatment components.
- Ongoing monitoring must follow the OWTS operation and maintenance manual or occur more frequently if required by the local agency or Regional Water Board.
- Where telemetry is not possible, the owner or owner's agent must inspect at least monthly while the system is in use and notify the service provider at least quarterly of observed operating parameters.
- For systems designed to meet disinfection requirements, a service provider must inspect proper operation quarterly while the system is in use unless continuous telemetric monitoring is capable of assessing operation.
- Quarterly effluent sampling and certified-laboratory requirements apply to systems subject to the disinfection provisions.
inspection frequency where telemetry is not possible: per monthly (While the system is in use.) · inspection frequency for disinfection systems: per quarterly (While the system is in use, unless continuous telemetric monitoring is capable of assessing operation.)
“Where telemetry is not possible, the owner or owner’s agent shall inspect the system at least monthly while the system is in use as directed and instructed by a service provider and notify the service provider not less than quarterly of the observed operating parameters of the OWTS. [...] OWTS in an Advanced Protection Management Program designed to meet the disinfection requirements in Section 10.10 shall be inspected for proper operation quarterly while the system is in use by a service provider unless a telemetric monitoring system is capable of continuously assessing the operation of the disinfection system.”
2023 OWTS Policy ↗Re-checked Sep 26, 2026
Well permitRequired
Construction, modification, or destruction of water wells in California.
- The permit is obtained from the applicable local environmental health agency or local water district before construction, modification, or destruction.
- Local enforcing agencies may adopt ordinances that meet or exceed DWR Well Standards.
- If no local well ordinance is adopted, the local enforcing agency must enforce the Statewide Model Well Ordinance.
- Water wells supplying public water systems have additional State Water Resources Control Board Division of Drinking Water certification requirements.
- Water-well construction must be performed by a licensed C-57 Well Drilling Contractor.
“Well owners need to obtain permits from local environmental health agencies or local water districts before construction, modification, or destruction takes place.”
Well Standards ↗Re-checked Sep 26, 2026
One more reviewed finding on this topic
- Limited — Construction, alteration, maintenance, or destruction of water wells, monitoring wells, cathodic protection wells, and geothermal heat exchange wells in California.
  “Permitting and enforcement are carried out by the LEAs, such as the County Department of Environmental Health.”
  Well Standards ↗Re-checked Sep 9, 2026
Subdividing landRegulated (with conditions)
Division of land in California that falls within the statutory definition of subdivision, including division for sale, lease, or financing.
- A parcel map is generally required unless a final or parcel map is otherwise required or the preparation is waived by local ordinance.
- Local ordinances may require a tentative map and may establish additional area, improvement, design, drainage, road, sanitary-disposal, water-supply, environmental-protection, and related requirements.
- Certain railroad-right-of-way and governmental or public-utility conveyances are excepted from the parcel-map requirement described in Government Code section 66428(a).
“A parcel map shall be required for subdivisions as to which a final or parcel map is not otherwise required by this chapter, unless the preparation of the parcel map is waived by local ordinance as provided in this section.”
California Government Code Section 66424 ↗Re-checked Sep 9, 2026
Driveway accessRequired
Driveways and driveway connections involving proposed encroachments within, under, or over State highway rights of way.
- The requirement applies to proposed activities related to placement of encroachments within, under, or over State highway rights of way.
- Applications are submitted to the appropriate District Encroachment Permits Office having jurisdictional authority over the site.
- Local or other agency requirements may also apply outside State highway rights of way.
“An encroachment permit must be obtained for all proposed activities related to the placement of encroachments within, under, or over the State highway rights of way.”
Encroachment Permits | Caltrans ↗Re-checked Sep 26, 2026
Permit processPublished (with conditions)
Construction, alteration, repair, movement, improvement, removal, conversion, or demolition of a building or structure in California.
- A separate permit for each building or structure must be obtained from the building official before the work.
- Code requirements vary by city and county; the applicable local building department must be consulted.
“no building or structure may be erected, constructed, enlarged, altered, repaired, moved, improved, removed, converted or demolished unless a separate permit [...] has first been obtained”
Do I need a building permit for my project? ↗Re-checked Sep 9, 2026
Campground & park staysLimited
Occupancy and use of manufactured homes and mobilehomes in California mobilehome parks and other locations subject to HCD jurisdiction.
- HCD administers titling and registration for manufactured homes and mobilehomes.
- HCD-inspected mobilehome parks are subject to health and safety enforcement where local government has not assumed enforcement.
- Manufactured/mobilehome park regulations address construction, use, maintenance, and occupancy.
- Separate local land-use, building, fire, health, and utility requirements may apply.
“MHs may be occupied outside or inside of mobilehome parks and installation and approval for occupancy is governed by the Mobilehome Parks Act (MPA), HSC Sections 18200, et seq., and Title 25, CCR Sections 1000, et seq.”
Manufactured & Mobilehomes ↗Re-checked Sep 26, 2026
2 more reviewed findings on this topic
- Limited — RV and trailer camping at Silver Strand State Beach Campground in the San Diego Coast District.
  “Camping Stay Limits: Applies to persons, equipment, or vehicles and any combination thereof [...] Maximum stay of 30 days per calendar year [...] Maximum 7 consecutive days during peak season (May 15 – September 15) [...] Maximum 14 consecutive days during non-peak season”
  Silver Strand State Beach Campground Rules and Regulations ↗Re-checked Sep 9, 2026
- Limited — Occupancy and use of recreational vehicles in California special occupancy parks and designated RV sections of mobilehome parks.
  “Unless otherwise allowed by a local ordinance, RVs generally may be occupied only in mobilehome parks or special occupancy parks governed by the Mobilehome Parks Act”
  What is a Mobilehome Park or Special Occupancy Park? ↗Re-checked Sep 26, 2026
county zoning authorityGeneral
California county legislative bodies' authority to adopt zoning ordinances regulating buildings, structures, land uses, lots, yards, open space, lot coverage, intensity of use, parking, loading, and setbacks within county jurisdiction, including unincorporated areas.
- The authority is exercised pursuant to Government Code Chapter 4, Zoning Regulations.
- The statute separately authorizes city legislative bodies; incorporated municipalities may exercise their own zoning authority.
- Government Code Section 65850 also lists authority to regulate signs and billboards, building and structure location, height, bulk, number of stories, and size, lot and open-space size and use, lot coverage, intensity of land use, offstreet parking and loading, and building setback lines.
- The cited section states it was amended by Stats. 2017, Ch. 376, Sec. 1, effective January 1, 2018.
“The legislative body of any county or city may, pursuant to this chapter, adopt ordinances that do any of the following:”
California Government Code Section 65850 ↗Re-checked Sep 21, 2026
county building authorityGeneral
California counties administering and enforcing state building standards through county building departments, including residential construction in unincorporated areas.
- Each county must maintain building standards and state building regulations in the office of the building official responsible for administration and enforcement of state building standards.
- The statewide Title 24 standards apply subject to statutory exceptions and any authorized local amendments or local requirements.
- The cited HCD bulletin concerns the 2019 California Building Standards Code and its July 1, 2021 supplement; later code editions may supersede those particular edition dates.
“These codes shall be maintained in the office of the building official responsible for the administration and enforcement of state building standards”
Information Bulletin 2021-02: 2019 California Building Standards Code Supplement ↗Re-checked Sep 26, 2026

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

Lot coverage — Residential development in unincorporated Yolo County.
Building in a floodplain — Development in floodplain or mapped flood-hazard areas of unincorporated Yolo County.
Short-term rentals — Short-term-rental land-use regulation in unincorporated Yolo County.

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Water rights & wells in Yolo County

Whether a new home can legally get its own water here — the sub-state groundwater regime, from California’s water agency.

Actively managed

This basin is under active state management — new water use is scrutinized, though a domestic well is usually still allowed.

Household wellPermit required — restricted

California requires no STATE permit for a domestic well — wells are permitted by the county — but under SGMA a Groundwater Sustainability Agency can meter or restrict new wells in medium/high-priority and critically overdrafted basins, and Executive Order N-7-22 requires counties in those basins to get GSA verification that a new well is consistent with the Groundwater Sustainability Plan before permitting.

Limit: 2 acre-feet/year de minimis under SGMA (Water Code §10721(e)) — largely exempt from GSA metering/fees

California DWR / State Water Board — SGMA de minimis & EO N-7-22 Action 9 FAQ ↗

Sacramento Valley high-priority subbasinspartial of county
High-priority SGMA subbasins (Corning, Colusa, Vina, Antelope-Tehama, South Yuba, North & South American, Solano, Yolo) with adopted GSPs; a new well is subject to GSA/EO N-7-22 consistency review.
California DWR — SGMA Basin Prioritization ↗

Hybrid state (appropriation + riparian). Groundwater rules change and basin boundaries follow the aquifer, not the county line — confirm current well and appropriation rules with the California state water agency before you buy or drill.Groundwater governance as of Jul 2026, cited to each administering agency.

Living off-grid in Yolo County, California

Is Yolo County a good place to live off-grid or homestead?

Yolo County scores 35/100 on the Bolthole Index, a marginal county profile. Watch-outs: about 148,865 people within 15 miles and elevated mid-century heat, water, rain, or wildfire exposure.

Do you need a building permit in Yolo County, California?

Yolo County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Yolo County Environmental Health Division - Onsite Wastewater Treatment System Program. Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

Can you live in an RV or tiny home on your land in Yolo County?

Living in an RV on your own land in Yolo County is allowed on a temporary basis only: Statewide rule. Occupancy of recreational vehicles as residential units in California. RVs are not intended for occupancy as permanent dwellings. Unless a local ordinance allows otherwise, RV occupancy generally is limited to mobilehome parks or special occupancy parks governed by the Mobilehome Parks Act or Special Occupancy Parks Act. A tiny home is allowed. Confirm with the county before relying on it.

How much does land cost in Yolo County, California?

Land in Yolo County runs about $10,780 per acre, based on the latest county data.

What is the water situation in Yolo County?

Yolo County gets about 21.4" of rain a year, with severe drought in roughly 42.2% of years. On water rights, Yolo County lies in the Sacramento Valley high-priority subbasins — High-priority SGMA subbasins (Corning, Colusa, Vina, Antelope-Tehama, South Yuba, North & South American, Solano, Yolo) with adopted GSPs; a new well is subject to GSA/EO N-7-22 consistency review..

How remote is Yolo County?

A typical private-land location has about 148,865 people within 15 miles and 8,677,754 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

Building permits, zoning and land rules in Yolo County, California

At a glance

Who to call

Do you need a building permit in Yolo County, California?

Who is the Yolo County building department, and how do you reach them?

Does Yolo County have zoning?

How do septic permits work in Yolo County?

Can you live in an RV or tiny home on your land in Yolo County?

What are the steps to build a home in unincorporated Yolo County?

What should you check before you buy land in Yolo County?

Watch-outs

Sources

Yolo County in California

How Yolo County scores

Find land. Bring the promising ones back.

Parcel due diligence

Answers from the rulebook for Yolo County

Yolo County rules

California rules that apply here

Still unanswered

Water rights & wells in Yolo County

Living off-grid in Yolo County, California

Is Yolo County a good place to live off-grid or homestead?

Do you need a building permit in Yolo County, California?

Can you live in an RV or tiny home on your land in Yolo County?

How much does land cost in Yolo County, California?

What is the water situation in Yolo County?

How remote is Yolo County?

How Yolo compares in California