You’re a California resident in need of a new home that doesn’t compromise high-quality or modern design at an affordable price. With median home prices in California among the highest in the country, (upwards of $950,000!) that combination can feel like a long shot.
Then you discover the world of modular homes and it looks perfect for you. Modern design, reasonable pricing, and high quality craftsmanship? It just feels right.
But now you’re left to figure out if this dream is actually possible. California modular homes follow a different regulatory path than traditional stick-built construction. State-level approval from HCD, county-level permitting, zoning rules that vary by jurisdiction, and paperwork most homeowners have never encountered before.
At Zook Cabins, we’ve guided California homeowners through this process from understanding what HCD certification actually covers to navigating county permit offices that don’t always know how to handle a modular project.
This guide breaks down everything you need to know about California modular home regulations, including permits, zoning, costs, and where to turn when your specific county raises questions this guide can’t answer.
Modular Home Requirements by County in California
| Alameda County | Alameda County Code of OrdinancesAlameda County Government Website |
| Alpine County | Alpine County Planning Department |
| Calaveras County | Calaveras County Planning DepartmentCalaveras County Building Department |
| Colusa County | Colusa County Community Development DepartmentColusa County Zoning Code |
| Contra Costa County | Contra Costa County Building RegulationsContra Costa County Code Enforcement |
| Del Norte County | Del Norte County Planning DepartmentDel Norte County Codes |
| El Dorado County | El Dorado County Planning and Building DepartmentsEl Dorado County Uniform Building Code |
| Fresno County | Fresno County Building SafetyFresno County Building and Safety FAQs |
| Humboldt County | Humboldt County Planning and Building DepartmentHumboldt County Code |
| Imperial County | Imperial County Building Division |
| Inyo County | Inyo County Building & Safety Department |
| Kern County | Kern County Code of OrdinancesKern County Public Works Department Code Compliance |
| Kings County | Kings County Building OrdinanceKings County Community Development Agency |
| Lake County | Lake County Community Development DepartmentLake County Code Of Ordinances |
| Lassen County | Lassen County Planning & Building Services |
| Los Angeles County | Los Angeles County Code Of Ordinance |
| Madera County | Madera County Building DivisionMadera County Municipal Code |
| Marin County | Marin County Building Code |
| Mariposa County | Mariposa County Planning DepartmentMariposa County Building DepartmentMariposa County Code |
| Mendocino County | Mendocino County Planning & Building ServicesMendocino County Code of Ordinances |
| Merced County | Merced County Planning DepartmentMerced County Code of Ordinances |
| Modoc County | Modoc County Building DepartmentModoc County Planning DepartmentModoc County Building Regulations |
| Mono County | Mono County Building Regulations |
| Napa County | Napa County Planning, Building, & Environmental ServicesNapa County Building Code |
| Nevada County | Nevada County Planning Department |
| Orange County | Orange County Development ServicesOrange County Building Regulations |
| Placer County | Placer County Community Development |
| Plumas County | Plumas County Building DepartmentPlumas County Planning Department |
| Riverside County | Riverside County Building & Safety DepartmentRiverside County Building Regulations |
| Sacramento County | Sacramento County Home Page |
| San Benito County | San Benito County GovernmentSan Benito County Code Of Ordinances |
| San Bernardino County | San Bernardino County Land Use Services |
| San Diego County | San Diego Planning & Development ServicesSan Diego County Building Code |
| San Francisco County | San Francisco Building DepartmentSan Francisco Planning DepartmentSan Francisco Building Codes |
| San Joaquin County | San Joaquin Community DevelopmentSan Joaquin Building Regulations |
| San Luis Obispo County | San Luis Obispo Planning & Building DepartmentSan Luis Obispo County Building Regulations |
| Santa Barbara County | Santa Barbara County Planning & Development DepartmentSanta Barbara County Building Regulations |
| Santa Clara County | Santa Clara County Planning & Development DepartmentSanta Clara County Code of Ordinances |
| Santa Cruz County | Santa Cruz County Planning Department |
| Shasta County | Shasta County Building DivisionShasta County Building Regulations |
| Sierra County | Sierra County Planning DepartmentSierra County Building DivisionSierra County Building Code |
| Siskiyou County | Siskiyou County Planning DepartmentSiskiyou County Building DepartmentSiskiyou County Building Regulations |
| Solano County | Solano County Building & Safety ServicesSolano County Building Standards & Codes |
| Sonoma County | Sonoma County Building DivisionSonoma County Building Regulations |
| Stanislaus County | Stanislaus County Planning & Community Development DepartmentStanislaus County Building Code |
| Sutter County | Sutter County Planning & Zoning DepartmentSutter County Building Code |
| Tehama County | Tehama County Building & Safety DepartmentTehama County Building Codes |
| Trinity County | Trinity County Building DivisionTrinity County Building Code |
| Tulare County | Tulare County Building DepartmentTulare County Building Regulations |
| Tuolumne County | Tuolumne County Building Division |
| Ventura County | Ventura County Government WebsiteVentura County Building Regulations |
| Yolo County | Yolo County Building ServicesYolo County Building Regulations |
| Yuba County | Yuba County Building Standards Construction Code |
Does Alameda County, California Allow Modular Homes?
Yes! Alameda County welcomes modular homes that carry the official HCD insignia. Under county rules, a qualifying factory-built home with proper HCD approvals and insignia is reviewed as a standard single-family dwelling, not under manufactured-home or mobile home regulations.
Most residential parcels fall under R-1 zoning, which allows one dwelling per site, requires a 5,000-square-foot minimum lot (unless modified by a “B” combining district), a 50-foot median lot width (60 feet for corner lots), and street frontage. Setbacks typically run 20 feet front and rear, 5 feet interior side , and 10 feet street-side, with a maximum height of 25 feet and two stories.
For more details, consult with the county planning department before starting a modular home project. If you live within incorporated Alameda County, you can go directly to your city zoning and planning departments to find out the regulations.
Does Alpine County, California Allow Modular Homes?
It does! Homeowners building a modular or factory-built home in Alpine County work with the Community Development Department’s Building Safety Division (530-694-2140, communitydevelopment@alpinecountyca.gov, 50 Diamond Valley Road, Markleeville).
The process will start with an online permit application and a complete, scaled PDF plan set, followed by outside-agency approvals, plan review, fee payment, and finally foundation, installation, utility, and inspection sign-offs.
If you plan to purchase a modular home within the county, it’s important to know about two critical permits. Environmental Health must sign off on your well and septic system before the building official can issue anything, and depending on your community, you may need a will-serve letter from a local water provider. Fire safety is another major factor and homeowners can expect requirements for 30–100 feet of defensible space, separate review of access roads and water supply, and potentially 2,500 gallons of on-site fire water if an adequate water system isn’t available.
These all come with a variety of fees homeowners should budget for. If you live within a city or municipality in Alpine County, you can go directly to your local building department to find out more.
Does Calaveras County, California Allow Modular Homes?
Yes, modular homes are allowed across CA, including Calaveras County. If you are a homeowner in this county interested in modular homes, you can start by working directly with the local zoning and planning department.
Within unincorporated areas, detached homes are permitted by right in the county’s RR, R1, R2 and R3 residential zones. The standard front and street-side setback is 20 feet from the property line or 50 feet from the road centerline, whichever creates the larger setback. Interior side setbacks are 10 feet in RR, 5 feet in R1 and R2, and 10 feet in R3, while the rear setback is 20 feet. Maximum building height is 35 feet in RR, R1 and R2 and 45 feet in R3.
A modular home must have its factory construction approved through California HCD, but Calaveras County will handle the foundation, installation, utility connections and local inspections. Approved plans need a scaled site plan showing all the details for the site.
For budgeting context, the county’s fee schedule effective August 8, 2026 lists a $5,701 base permit fee for a new single- or two-family dwelling, with $2,850.50 due at submittal. Potential additions include a $4,429 primary-dwelling road-impact fee, school fees of approximately $5.17–$5.25 per square foot, fire-district charges, septic review, grading and driveway-encroachment permits.
Before purchasing the home, look up the parcel through Calaveras County’s zoning resources and contact the Planning and Building Departments at 209-754-6390 for written confirmation of zoning, foundation requirements and permit classification. Properties inside the City of Angels Camp are reviewed by the city rather than the county.
Does Colusa County, California Allow Modular Homes?
Yes. Colusa County allows modular homes that meet California and local building-code requirements. The county defines modular homes separately from manufactured and mobile homes, meaning a qualifying modular home is generally reviewed as a conventional single-family dwelling. Single-family homes are permitted in the R-R, R-1 and R-2 residential zones and in several agricultural zones. Minimum parcel sizes include 2 or 5 acres in R-R zones, 6,000 square feet in R-1-6 and 8,000 square feet in R-1-8.
In R-R and R-1 zones, the typical front and rear setbacks are 20 feet. Interior side setbacks are 10 feet in R-R and 6 feet in R-1, while street-side setbacks are 10 and 8 feet, respectively. Maximum home height is 30 feet. The home must comply with the 2025 California Building Standards Code, effective January 1, 2026, and the factory-built sections must carry California HCD approval.
Before ordering a home, use the Colusa County zoning map to confirm the parcel’s exact zoning and check whether it needs a septic system, well, floodplain review, driveway permit or additional fire-access improvements. Applications are submitted through the county’s Online Permit Portal. Homeowners can contact the Colusa County Planning and Building Department at 530-458-0480 for zoning verification and a project-specific fee estimate. Properties inside the incorporated cities of Colusa or Williams are subject to city requirements instead of county zoning rules.
Does Contra Costa County, California Allow Modular Homes?
It does! Contra Costa County allows California HCD-approved modular homes wherever the parcel’s zoning permits a detached single-family residence. The county has several single-family residential districts, including R-6 through R-100. In the common R-6 district, the minimum lot size is 6,000 square feet with 60 feet of width. Standard requirements include a 20-foot front setback, a 5-foot minimum side setback with 15 feet of total side-yard space, a 15-foot rear setback and a maximum height of 35 feet or 2½ stories. Planned-development districts, hillside rules and parcel-specific overlays may impose different standards.
Homeowners should first locate the parcel in CCMAP, confirm the zoning with the Planning Division and then submit the HCD plans, foundation design and site plan through the ePermits Center. The county Application and Permit Center can be reached at 925-655-2700.
Does Del Norte County, California Allow Modular Homes?
Yes. Like the rest of CA, Del Norte County permits HCD-approved modular homes as detached single-family residences whenever the parcel’s zoning allows that use. Requirements vary by district. For example, the inland R-2 district permits a single-family home or duplex on a minimum 7,200-square-foot lot that is at least 60 feet wide. The maximum lot coverage is 35%, with a 25-foot front setback, 5-foot side setbacks, a 20-foot rear setback and a maximum building height of 35 feet. Coastal properties are regulated under Title 21 rather than the county’s inland Title 20 zoning rules.
The county will handle all the inspections after the house is installed. The county’s engineering fee schedule lists a $200 initial building-permit review and a $75 driveway inspection, separate from building, planning and other agency fees. Before purchasing a home, check the county GIS map and contact Planning at 707-464-7254 to confirm zoning and coastal status, followed by Building at 707-464-7253 for the required permit package.
Does El Dorado County, California Allow Modular Homes?
Absolutely. El Dorado County homeowners will be glad to hear that the county is very open to HCD-approved modular homes as detached single-family dwellings in the RM, R1, R20K, R1A, R2A, R3A and RE zones.
In R1, the minimum lot size is 6,000 square feet, with a 20-foot front setback, 5-foot side setbacks, a 15-foot rear setback and a 40-foot height limit. R20K requires 20,000 square feet with 30-foot front and rear setbacks and 10-foot side setbacks. R1A requires one acre, 30-foot front and rear setbacks, 15-foot side setbacks and a 45-foot height limit. On parcels of one acre or more, Fire Safe rules may require structures to remain 30 feet from property lines or roads unless an exception is approved.
We recommend that homeowners confirm the parcel’s zoning and fire district before submitting the HCD-approved home plans with the county’s single-family dwelling and foundation documents. Contact Building Services at 530-621-5315 or Planning at 530-621-5355. Properties in the Tahoe Basin may also require compliance with Tahoe Regional Planning Agency standards.
Does Fresno County, California Allow Modular Homes?
Yes. In Fresno County’s R-1 zone, newly created parcels generally require at least 6,000 square feet, with a 20-foot front setback, 5-foot interior side setbacks, a 10-foot street-side setback and a 20-foot rear setback. Maximum lot coverage is 40%, and the current maximum height is 25 feet without discretionary approval. Rural Residential parcels generally require 2 acres with 35-foot front, 20-foot side and 20-foot rear setbacks and a 35-foot height limit. Overlays, recorded subdivision standards and legally undersized parcels can change these numbers.
Another important note is that an engineered grading and drainage plan is generally required when more than 1,000 cubic yards of soil will be moved, although steep or complicated sites may require one below that threshold. This is important for homeowners looking at foundation requirements.
Start by confirming the parcel’s zoning with Fresno County Development Services, then submit through the Citizens Portal; Building and Safety can be reached at 559-600-4560. Properties inside Fresno, Clovis or another incorporated city must follow that city’s permitting rules.
Does Humboldt County, California Allow Modular Homes?
It definitely does. Humboldt County follows the rest of CA laws and approves modular homes in zones where a single-family residence is permitted. A common inland R-1 parcel has a 5,000-square-foot minimum, while the coastal RS-5 zone requires 5,000 square feet and at least 50 feet of lot width. Typical standards include a 20-foot front setback, 5-foot interior side setbacks, a 10-foot rear setback and a 35-foot maximum height. Combining zones can increase these requirements; for example, a B-4 overlay can raise an R-1 parcel’s minimum size to 1 acre, and Fire Safe regulations may require a 30-foot building setback on parcels of 1 acre or larger.
Humboldt County reviews the foundation, utilities and local inspections after the factory sections receive HCD approval. A soils report may be required on steep or high-seismic sites and a grading plan may be required when 50 cubic yards or more are moved. Coastal parcels also require a Coastal Development Permit.
We suggest that you use the county GIS to check zoning, coastal status, fire hazards and flood zones, then apply through Accela or contact Planning and Building at 707-445-7245.
Does Imperial County, California Allow Modular Homes?
It does. Modular construction is a workable option in unincorporated Imperial County when the property allows a residence and the home is approved through California’s Factory-Built Housing program. In the R-1 zone, a primary home generally requires a 25-foot front setback, reduced to 20 feet on an existing lot less than 90 feet deep; 5-foot interior side setbacks; a 15-foot street-side setback on corner lots; and a 25-foot rear setback. Residential buildings are limited to three stories or 40 feet. New R-1 development must also have sewer service, treated water and streets built to county standards.
California HCD reviews the factory-built sections, while Imperial County reviews things like permanent foundation, site placement, utility connections and inspections. Before ordering the home, contact Imperial County Planning and Development Services at 442-265-1736 to confirm zoning and the required foundation package.
Does Inyo County, California Allow Modular Homes?
Yes, Inyo County provides a path for an HCD-approved modular home to be installed as a permanent residence on a qualifying parcel. A common R1-5,800 district requires at least 5,800 square feet of land and 50 feet of lot width, with a 25-foot front setback, 5-foot side setbacks and a 20-foot rear setback. Buildings are generally limited to 2½ stories. Zoning suffixes such as R1-0.5 and R1-1.0 can instead require a half-acre or full-acre parcel, so the exact designation matters.
The county requires a building permit for the foundation and other onsite construction. Depending on the location, homeowners may also need grading, septic or well approval, fire-access review and engineering for snow, seismic or soil conditions. Start with the Inyo County Planning Department at 760-878-0263 to verify the parcel’s zoning, then contact Building and Safety at 760-873-7857 for the plan and inspection requirements before purchasing the home.
Does Kern County, California Allow Modular Homes?
Kern County gives homeowners a clear route to place modular housing on property zoned for a single-family residence. In the common R-1 district, the minimum lot size is generally 6,000 square feet, with one primary dwelling allowed per legal lot. The front setback is measured from the road centerline and mandates 55 feet from a local street and 70 feet from a secondary highway, while typical side and rear setbacks are 5 feet. Maximum building height is three stories or 35 feet.
For Kern County, a new-home application generally requires three plan sets, energy documents and structural calculations for construction that falls outside standard code provisions. Check the parcel through Kern County’s zoning resources, then contact Planning at 661-862-5263 and Building Inspection at 661-862-8650 before submitting through the Citizen Portal.
Does Kings County, California Allow Modular Homes?
Yes, Kings County generally permits a California HCD-approved modular home on an unincorporated parcel where a detached single-family residence is allowed. The county uses several residential districts, including RR and the R-1-6, R-1-8, R-1-12 and R-1-20 districts, so there is no single minimum lot size for every property. Typical residential standards include front setbacks of 15 to 25 feet, 5-foot side setbacks, a 10-foot rear setback and a maximum building height of 30 feet. Some districts allow approximately 40% lot coverage, but combining districts, neighboring agricultural uses and recorded subdivision restrictions can increase the required setbacks.
Before ordering a beautiful new modular home, confirm the parcel’s complete zoning designation and submit a preliminary site plan to the Community Development Agency. Zoning and Building staff can be reached at 559-852-2670. Properties inside Hanford, Lemoore, Corcoran or Avenal follow city permitting rules.
Does Lake County, California Allow Modular Homes?
Lake County permits modular residences, but the property’s water and wastewater setup can substantially change the minimum lot size. In the R1 single-family residential district, the minimum is 6,000 square feet when both public water and sewer are available, 15,000 square feet when only one public system is available and 40,000 square feet when the home requires both a private well and septic system. The front setback is 20 feet from the property line or 45 feet from the road centerline, whichever is greater. Side setbacks are 5 feet, rear setbacks are 15 feet for a one-story home and 20 feet for a taller home, and maximum height is 35 feet. Maximum lot coverage is 35% for a one-story home and 30% for a two-story home.
When it comes time to install and inspect the modular home, there will be additional fees for the homeowners. To learn more about the modular home process, start with Lake County Planning at 707-263-2221, followed by Building and Safety at 707-263-2382.
Does Lassen County, California Allow Modular Homes?
A modular home can be approved in Lassen County through the same basic zoning path used for a site-built single-family residence. In the R-1 district, one detached single-family dwelling is permitted by right. The standard front and rear setbacks are 20 feet. Each side setback is normally 10% of the lot width, up to a maximum of 15 feet, although design review may reduce it to 5 feet. Maximum lot coverage is 35%, and the normal height limit is 25 feet; design review can allow a height of up to 35 feet. Because Lassen County also uses building-site and other combining districts, homeowners must check the parcel’s complete zoning designation rather than relying on “R-1” alone.
Full new-home applications are submitted using the county’s building application rather than the limited online portal, which currently covers simpler permits such as electrical, plumbing, mechanical and reroofing work. Contact Lassen County Planning and Building Services at 530-251-8269 to confirm zoning, septic or sewer requirements, access and the required plan package. Properties within Susanville are handled by the city.
Does Los Angeles County, California Allow Modular Homes?
Yes! Los Angeles County permits California HCD-approved modular homes in unincorporated areas where the zoning allows a detached single-family residence. The A-1, R-A and R-1 zones all permit single-family homes and generally use a 20-foot front setback, 5-foot interior side setbacks, a 10-foot reverse-corner side setback and a 15-foot rear setback. The standard maximum height is 35 feet. Community Standards Districts, coastal regulations, hillside rules and local area plans can impose stricter requirements on individual parcels.
Los Angeles County reviews the permanent foundation, site placement, utility connections and onsite construction for modular homes so homeowners will need to go through them when the time comes. Enter the address or parcel number into the county’s Z-NET zoning lookup before choosing a home design. A planner can then confirm whether fire access, grading, septic, floodplain or discretionary planning approval will be required. Regional Planning can be reached at 213-974-6411. Properties inside any of Los Angeles County’s 88 incorporated cities must be reviewed by that city instead.
Does Madera County, California Allow Modular Homes?
It does. Madera County provides several zoning paths for modular housing, ranging from compact residential lots to large rural parcels. Regarding zoning laws, the county states that in the RUS urban single-family zone, the current standards generally require at least 4,500 square feet, a 25-foot front setback, 3.5-foot side setbacks, a 10-foot rear setback and a maximum height of 35 feet. Rural standards are much larger: RRS-1 requires 1 acre, while the RRS-5 and RRS-10 classifications use minimum lot areas of approximately 4.5 and 9 acres. Those rural districts generally require 25 feet in front, 10 feet on the sides and 20 feet in the rear.
The factory modules must have state HCD approval, while Madera County handles the foundation, installation and local building inspections. Building applications and PDF plans can be submitted through the county’s online permit system, but zoning entitlements must be coordinated directly with the Planning Division. We recommend you have Planning verify the complete zoning suffix before the manufacturer finalizes the foundation or floor plan.
Does Marin County, California Allow Modular Homes?
Yes. In Marin County, the fact that a house is modular is usually less important than the parcel’s zoning status and design-review requirements. The conventional RA, RR, RE, R1 and R2 standards generally require a minimum 7,500-square-foot parcel, a 25-foot front setback, 6-foot interior side setbacks and a 10-foot street-side setback. The rear setback is 20% of the lot depth, capped at 25 feet, while the normal height limit is 30 feet and maximum floor-area ratio is 0.30. Planned districts, community plans and hillside or coastal regulations can replace these baseline numbers.
Marin County reviews the modular home’s foundation, site work and building permit after HCD approves its factory construction. A residence exceeding 3,500 square feet generally requires Design Review, and property in the Coastal Zone may need a Coastal Permit before construction plans can move forward. Septic approval and fire-department review are also common on rural parcels.
To take the next step, you can check the address through Marin County’s zoning lookup, then discuss coastal or hillside constraints with Planning at 415-473-6269 before paying a nonrefundable modular-home design deposit. Building and Safety can be reached at 415-473-6550.
Does Mariposa County, California Allow Modular Homes?
It sure does! Modular homes are permitted in Mariposa County when the property is zoned for residential use and the home qualifies as California factory-built housing rather than a mobile or manufactured home. The county’s Rural Residential Zone allows residential development and generally requires at least 2.5 acres with community sewer service or 5 acres without it, at a density of one primary home per 2.5 acres. Setbacks vary considerably because Mariposa County has 11 separate Town Planning Areas, but California Fire Safe Regulations commonly require at least 30 feet between a new residence and property lines in State Responsibility Areas.
The Mariposa County Building Department reviews the foundation, utilities and final installation. One unusual local rule is that the county will not accept a permit application on a parcel with an unresolved code violation unless the new permit is intended to correct that violation. Homeowners should enter the address or APN into the county’s Public Zoning Lookup Tool before designing the foundation, then discuss the results with Planning at 209-966-5151 and submit the building application through the Mariposa Development Services Permit Center.
Does Mendocino County, California Allow Modular Homes?
A California-approved modular home can serve as a permanent single-family residence in unincorporated Mendocino County, but the rules depend heavily on whether the property is inland or inside the Coastal Zone. In the inland R-R Rural Residential district, minimum parcel sizes range from 40,000 square feet to 10 acres. The smaller L-1 and L-2 tiers generally require 20-foot front and rear setbacks, while the L-5 tier increases them to 30 feet and the L-10 tier to 50 feet. Coastal parcels follow a different zoning code and may require a Coastal Development Permit, biological review, visual-resource protection or additional bluff and water-supply documentation.
The state approves the factory-built structure, but Mendocino County still requires plans for the foundation, site layout, utilities and onsite work. A well or septic permit may be needed through Environmental Health, and the county currently estimates approximately 6–8 weeks for building plan review. Permit documents and building plans can be submitted digitally.
Because coastal boundaries and combining districts are not always obvious, homeowners can use the county Zoning Web Map or request a formal Letter of Zoning; that letter currently begins with a $152 deposit covering the first hour of research.
Does Merced County, California Allow Modular Homes?
Yes, Merced County expressly allows single-family homes that are conventionally constructed or manufactured off-site and placed on a permanent foundation. In the R-1 zone, a newly created interior lot must contain at least 6,000 square feet, with a 20-foot front setback, 5-foot interior side setback, 20-foot street-side setback and 15-foot rear setback. Maximum building coverage is 60%, and the primary structure may be up to 30 feet tall. Rural Residential standards are larger: a parcel without public water and sewer generally requires one net acre, a 50-foot front and street-side setback, 15-foot interior sides and a 25-foot rear setback.
Before a building permit can be issued, the project must receive zoning clearance and any required approvals from Roads, Environmental Health and the fire authority. Merced County reports an initial plan-check period of roughly 4–6 weeks after it receives complete plans and the plan-check fee. Applications can be filed through the county’s online Permitting and Licensing Portal, and Building and Safety can be reached at 209-385-7477.
Does Modoc County, California Allow Modular Homes?
Yes! Modoc County permits factory-built homes as detached single-family dwellings wherever zoning allows a single-family use, including the R-1 and residential-high density districts. Modoc is also unusual for its widespread Agricultural Exclusive zoning, where a landowner can perform a one-time “homestead split” separating an existing dwelling from a larger AE-zoned parcel. This is helpful if you are interested in a rural piece of land.
Modoc County Planning Department handles zoning and use permits while the Building and Safety Department handles construction permits and inspections. Given Modoc’s rural, high-desert terrain, we recommend that homeowners confirm site-specific snow and wind load criteria with Building and Safety early, since standard low-elevation roof packages may not be adequate.
Does Mono County, California Allow Modular Homes?
Yes, and Mono County has unusually specific, written standards for it. Modular housing is permitted in every district zoned for conventional single-family use — SFR, ER, RR, MFR-L, RU, RM, AG, and OS — and is allowed in the MU designation subject to Director Review, with design standards meant to keep the home visually compatible with stick-built construction.
In the Rural Residential zone, the minimum parcel size is 1 acre, minimum lot dimensions are 60 feet wide by 100 feet deep, maximum lot coverage is 40%, and setbacks are 20 feet front / 10 feet rear / 10 feet side with a 35-foot maximum building height.
For next steps, you can contact the Community Development Department Building Division and ask the staff about zoning requirements that are not available online.
Does Napa County, California Allow Modular Homes?
Modular homes are allowed in the districts zoned for residential use, but Napa County’s zoning is dominated by agricultural preservation rather than conventional residential districts, which is the single most important thing to understand before buying land here.
The county’s Agricultural Preserve district has a 40-acre minimum parcel size, and the Agricultural Watershed district has a 160-acre minimum, both raised from smaller historical minimums specifically to limit density and protect water and agricultural resources. In the county’s Residential Single (RS) district, the minimum lot size is 8,000 square feet, per Napa County code identifying the RS district’s minimum lot size as eight thousand square feet for second-unit eligibility purposes.
To move ahead with these zoning districts in mind, our recommendation is to contact Napa County Planning, Building & Environmental Services, 1195 Third Street, Suite 210, Napa, CA 94559, to confirm zoning and whether a use permit or administrative review applies before finalizing plans.
Does Nevada County, California Allow Modular Homes?
Yes. Nevada County permits modular homes as detached single-family dwellings in its residential and rural districts, including R1, R2, RA, AE, AG, FR, and TPZ. The R1 District implements the General Plan’s Urban Single-Family designation and allows single-family dwellings at densities of up to four dwelling units per acre, with setbacks reducible on parcels under three acres under the county’s building-setback provisions. Front yard setbacks along arterial and collector roads run 20 feet, measured from the existing or ultimate right-of-way, whichever is greater.
Two site factors matter more here than in most counties and the first is that Nevada County is a declared snow area. Snow loads vary throughout the county, so site-specific engineering is required before a manufacturer finalizes the home. And because Nevada County includes Grass Valley, Nevada City, and Truckee-area terrain with significant wildfire exposure, state law (PRC 4291) requires 100 feet of defensible space around improved buildings in the State Responsibility Area.
Contact the Community Development Agency Building Department at (530) 265-1222, which also handles permit submission through the Accela Citizen Access portal; septic and water approval from Environmental Health is required before a new-residence building permit is issued.
Does Orange County, California Allow Modular Homes?
Orange County allows California-approved modular homes on unincorporated property where the zoning permits a detached single-family residence. In the county’s R1 district, the baseline minimum lot size is 7,200 square feet. A home generally must remain 20 feet from the front property line, 5 feet from interior side lines and approximately 25 feet from the rear, with a maximum height of 35 feet. Coastal areas, planned communities, hillside parcels and local development overlays can replace these basic standards with stricter requirements.
The factory-built sections must carry California HCD approval, while Orange County checks the foundation, grading, utility connections and onsite installation. Applications are handled through the county’s myOCeServices system. Before finalizing a floor plan, have OC Development Services confirm the parcel’s zoning and grading, since this impacts whether the manufacturer is able to deliver and install the modular home.
Does Placer County, California Allow Modular Homes?
Yes, Placer County treats a qualifying modular home as the permanent single-family dwelling it becomes after installation. In the Residential Single-Family, or RS, district, a newly created parcel may contain as little as 3,500 square feet, although 20,000 square feet is required when both a private well and onsite septic system are needed. The usual front setback is 20 feet. Side yards must total 15 feet, with no individual side smaller than 5 feet for a one-story home or 7.5 feet for a two-story home. Rear setbacks are 10 feet for one story and 20 feet for two stories.
Placer County reviews the site plan and inspects the permanent foundation after HCD approves the factory modules. New-home plans are filed through ePermits using the county’s residential permit package, and separate fire-mitigation and school-development fees may apply.
If you reside in a Sierra or Lake Tahoe parcel, it’s important to note that these deserve an early zoning review because snow-load requirements, combining zones and Tahoe-area regulations can substantially affect the foundation and setbacks.
Does Plumas County, California Allow Modular Homes?
It definitely does. Plumas County’s residential zoning provides a straightforward path for using an HCD-approved modular home as the parcel’s primary dwelling. The 2-R district requires at least one-half acre, the 3-R district requires one-third acre and the 7-R district requires one-seventh acre. These zones generally require at least 60 feet of lot width, a 20-foot front setback and side and rear setbacks of 5 feet per building story. Homes may cover up to 50% of the property and reach 35 feet in height.
However, those zoning setbacks are not always the final numbers. Properties in a State Responsibility Area or Very High Fire Hazard Severity Zone may need 30 feet of separation from property lines or the road centerline unless approved mitigation is provided. The permit file must also address the county-designated snow load, septic or sewer service and well or public water. Plumas County reports that a complete building application typically takes about two to four weeks for initial review.
To move ahead, bring the parcel number to Planning and Building Services at 530-283-7011 before the manufacturer engineers the foundation; private septic and well questions go to Environmental Health at 530-283-6355.
Does Riverside County, California Allow Modular Homes?
Absolutely. Riverside County specifically allows factory-built housing in zones that permit a one-family dwelling, provided the home meets the same applicable development standards. In the R-1 zone, a newly created lot generally requires 7,200 square feet, 60 feet of average width and 100 feet of depth. The front setback is 20 feet, the street-side setback is 10 feet and the rear setback is 10 feet. Interior side yards equal 10% of the lot width but need not exceed 5 feet and cannot be less than 3 feet. Maximum coverage is 50%, and the height limit is three stories or 40 feet.
A private septic system requires Environmental Health approval, and properties governed by a specific plan or planned residential zone may follow different dimensions than standard R-1.
Start with the parcel’s APN in Map My County, then submit through PLUS Online. Planning can confirm the land-use rules at 951-955-3200, while Building and Safety handles permit questions at 951-955-1800. Be clear that the proposed home is factory-built housing rather than a HUD-code manufactured home, because the plan and permit classifications differ.
Does Sacramento County, California Allow Modular Homes?
A state-approved modular home may be installed as a permanent single-family residence in Sacramento County wherever the underlying zone permits that use. In the common RD-5 district, a newly created interior lot generally requires 5,200 square feet and 52 feet of width; a corner lot requires 6,200 square feet and 62 feet of width. The front setback is normally 20 feet, or 24 feet where a Public Utilities/Public Facilities easement applies. One- and two-story homes require 5-foot side setbacks and may reach 30 feet in height. The rear setback is 25 feet on lots deeper than 125 feet and otherwise equals 20% of the lot depth.
Utility availability can change whether the property is buildable at the expected density. A parcel using public water but no public sewer generally needs at least 1 acre, while a parcel with neither public water nor sewer generally needs 2 acres.
Our team recommends you use Sacramento County’s Residential Development Navigation Assistant to generate the necessary agency and permit checklist, then file the plans electronically through the county permit portal. Zoning and permit questions can be directed to 916-875-5296.
Does San Benito County, California Allow Modular Homes?
Yes, San Benito County permits California-approved modular homes on parcels where a single-family residence is allowed. In the R-1 zone, the minimum parcel size depends on utilities and is 5,000 square feet with public water and sewer, 1 acre with public water and a septic system, or 2.5 acres with a private well and septic. The standard front setback is 20 feet.
Each side yard must equal 10% of the lot width, with a minimum of 6 feet and maximum requirement of 20 feet, while the rear setback is 20% of the lot depth, between 20 and 35 feet. Maximum height for the modular home is 30 feet and lot coverage is limited to 40%.
San Benito publishes separate submittal requirements for new single-family dwellings, so homeowners should identify the proposed unit specifically as factory-built housing and ask which checklist applies. Parcels using wells or septic systems also need Environmental Health clearance. The best starting point is the county’s Residential Projects page, followed by a zoning review with Planning and Building at 831-637-5313.
Does San Bernardino County, California Allow Modular Homes?
It does! A modular home can be installed in San Bernardino County, but the development standards change between the Valley, Mountain and Desert regions. In a Valley or Desert RS district, the typical requirements are a 25-foot front setback, a 15-foot street-side setback along a local road, side yards of 5 feet on one side and 10 feet on the other, a 15-foot rear setback and a 35-foot height limit.
Mountain RS parcels generally require a 15-foot front setback when the lot is under 14,000 square feet and 25 feet on larger lots; side yards equal 20% of the lot width but need not exceed 15 feet, and the rear setback is 15 feet.
The county must approve the site plan, foundation and installation before the property is disturbed. Homeowners should check the parcel through the county zoning maps and then contact Land Use Services at 909-387-8311 for a written determination of the correct modular-home permit path. Applications and permit tracking are handled through EZ Online Permitting, or EZOP.
Does San Diego County, California Allow Modular Homes?
The good news is that it does! San Diego County allows factory-built modular housing on a permanent foundation when the parcel’s full zoning designation permits a dwelling. Instead of using one standard residential setback table, the county assigns separate designators for use, height, lot coverage and setbacks.
For example, setback designators J through N generally require 50 feet from the road centerline in front, 5 feet from an interior side line, 35 feet from the centerline of a side street and 25 feet in the rear. A G height designator allows up to 35 feet and two stories, while H allows 35 feet and three stories. Fire-code setbacks can be greater than the zoning numbers.
Because one letter in the zoning string can change the buildable envelope, homeowners should use the county’s zoning and property research tools before selecting a modular floor plan. San Diego County provides a Residential Dwelling Plan Submittal package and a permit-fee estimator; questions can be directed to the Building Division at 858-565-5920.
Does San Francisco County, California Allow Modular Homes?
While modular construction is legal in San Francisco, it does not bypass the city’s unusually detailed planning process. San Francisco is a consolidated city and county, so projects go through SF Planning and the Department of Building Inspection rather than a separate county office. On properties that remain in an RH residential district, dwellings are generally limited to 35 feet in height, and RH-1 properties commonly require a rear yard equal to 30% of the lot depth with a minimum of 15 feet.
However, the Family Zoning Plan took effect January 12, 2026 and changed height and density rules for many parcels, making an address-specific zoning lookup essential.
Any modular home must have California factory approval, while San Francisco reviews the foundation, structural connections, utilities, energy compliance, fire safety and inspections. A new home requires Planning Approval before the building permit moves forward.
Begin with SF Planning’s Find My Zoning tool and request a Planning Approval Letter before preparing the complete DBI construction package. For a modular project, delivery access and crane placement should also be studied early because the zoning approval does not guarantee that large modules can physically reach the property.
Does San Joaquin County, California Allow Modular Homes?
Yes, San Joaquin County can approve an HCD-compliant modular home as a permanent residence on property zoned for that dwelling type. In the R-L residential zone, the baseline minimum lot size is 5,000 square feet, with 50 feet of width and 65 feet of depth. A primary home has a 20-foot front setback, 5-foot side setbacks, a 10-foot rear setback and a 40-foot height limit. Where the road right-of-way is less than 50 feet wide, the front setback increases to 45 feet measured from the road centerline. Rural R-R parcels generally require 1 acre with 30-foot front and rear setbacks and 15-foot side yards.
The county requires a new-residence building permit for the onsite construction and installation. Since the county maintains different information for conventional residences and manufactured homes, applicants should ask Community Development to classify the unit as California factory-built housing before choosing an application type. Plans are submitted through the Accela Citizen Portal, and the department can be reached at 209-468-3121.
Does San Luis Obispo County, California Allow Modular Homes?
It does. San Luis Obispo County accepts modular construction where the parcel’s land-use category allows a single-family residence. Under the inland ordinance, residential uses generally require a 25-foot front setback. The rear setback is normally 10 feet on parcels smaller than 1 acre and 30 feet on parcels of 1 acre or more, while single-family, rural and suburban homes are generally limited to 35 feet in height.
Homeowners should also remember that San Luis Obispo County issues the construction permit for the foundation, installation and site work. Rural properties may need separate well, septic, grading and fire approvals, and coastal parcels may require a land-use or Coastal Development Permit before the building plans are accepted. S
We recommend you use the county’s Land Use View and zoning guide to identify the parcel’s land-use category and combining designations, then submit through PermitSLO or contact Planning and Building at 805-781-5600 for a parcel-specific review.
Does Santa Barbara County, California Allow Modular Homes?
Yes. Santa Barbara County allows a California approved modular home wherever the property permits a single-family residence. Residential zoning commonly includes R-1 and E-1 districts, with the number preceding the zone indicating the minimum parcel size; for example, 7-R-1 generally means 7,000 square feet, while 1-E-1 means 1 acre. A common R-1/E-1 front-yard rule requires the home to remain at least 20 feet behind the road right-of-way and 50 feet from the road centerline.
Coastal parcels may require a Coastal Development Permit, while properties in Montecito are governed by a separate land-use code. Before choosing a home width or foundation, enter the parcel into the county’s Find My Zoning system to find any final necessary reviews. Planning and building applications are submitted through the Accela Citizen Access portal.
Does Santa Clara County, California Allow Modular Homes?
Modular construction is allowed in unincorporated Santa Clara County, provided the finished home qualifies as a single-family dwelling and complies with the parcel’s zoning. In the R1 district, a newly created lot must generally contain at least 5,000 square feet, although an existing legal building site may be as small as 3,750 square feet. The standard setbacks are 25 feet in front, 5 feet on interior sides, 10 feet on the street-facing side of a corner lot and 25 feet in the rear. The normal limit is 35 feet and two stories. Lot-size combining districts, scenic roads and flag lots can produce stricter standards.
A planning land-use application is generally required for a new residence before the building permit is issued. The county also requires planning review for grading exceeding 500 cubic yards or 5 feet in vertical depth, as well as construction in scenic-road, historic or design-review districts. Use Property Explorer to confirm that the land is actually within the county’s jurisdiction, then schedule a planning-submittal appointment; building, grading and fire permits can be managed through the Public Permit Portal. The Permit Center can be reached at 408-299-5700.
Does Santa Cruz County, California Allow Modular Homes?
Yes! Santa Cruz County permits HCD-approved modular homes in its RA, RR, R-1 and RB residential districts, where detached single-family homes are allowed by right. The number attached to an R-1 designation identifies the minimum land area per dwelling, so R-1-6 means 6,000 square feet per unit. In the common R-1-6 through R-1-9 range, the home may cover up to 40% of the lot and reach 28 feet in height. The setbacks are 20 feet in front, 5 feet on one interior side, 8 feet on the other, 10 feet along a side street and 15 feet in the rear.
A Coastal Development Permit or Site Development Permit may be needed even though the residential use itself is permitted, and parcels within a State Responsibility Area can be subject to larger fire-safe setbacks. The residential submittal should address the permanent foundation, septic or sewer service, soils conditions, drainage and module installation.
Begin with the county GIS and residential application requirements before preparing the full ePlan package. If you live within an incorporated area, you can connect directly with your town or city’s planning and zoning departments.
Does Shasta County, California Allow Modular Homes?
It appears that way. Shasta County accepts state-approved modular homes on land where zoning allows a one-family residence. In the R-1 district, the standard front setback is 20 feet, the two side yards are generally 5 feet and 12 feet, and the rear setback is 15 feet. Maximum height is 30 feet. Rural Residential parcels under 1 acre use similar 20-foot front, 5-foot and 12-foot side, and 10-foot rear standards. On parcels of 1 acre or more, wildfire rules may require buildings to remain at least 30 feet from every property line and road easement.
The county’s review covers the foundation, onsite installation and utilities. Snow loads vary considerably across Shasta County, and a California engineer or architect is generally required where the site’s ground snow load exceeds 70 pounds per square foot.
We suggest you check the parcel in the Zoning Plan Explorer and ask Planning to confirm any fire, flood or combining-zone constraints before the modular manufacturer completes its engineering. Building applications are accepted through Build Shasta, and the Building Division’s number is 530-225-5761.
Does Sierra County, California Allow Modular Homes?
A modular home can be used as a permanent residence in Sierra County when the zoning permits a single-family dwelling. In the R-1 district, the normal standards are a 20-foot front setback, 5-foot side setbacks, a 25-foot rear setback and a 35-foot height limit. Sierra County also has numerous Rural Residential districts with parcel-size designations ranging from roughly 1 to 10 acres. Recorded subdivision notes, scenic areas, floodplains and water-resource setbacks can further reduce the buildable portion of the property.
Snow engineering is a major part of the approval process. Sierra County’s 2026 residential checklist states that the minimum ground snow load exceeds 70 pounds per square foot countywide, so all nonexempt structures require engineered plans. New homes also require residential fire sprinklers, wildfire-resistant materials, a foundation plan and approval for sewage disposal, wells or public water.
Because the county does not maintain a fully updated digital zoning map, send the parcel number directly to Planning and Building at 530-289-3251 before ordering the home or finalizing delivery access.
Does Siskiyou County, California Allow Modular Homes?
Yes. Siskiyou County allows HCD-approved modular homes on parcels where a single-family residence is permitted. The county’s adopted Housing Element lists the Rural Residential zone with a 7,200-square-foot minimum lot when public utilities are available, increasing to 1 acre when septic is required. Maximum lot coverage is 40%, and the height limit is 35 feet. The Res-1 district also uses a 7,200-square-foot minimum—or 1 acre with septic—with 40% coverage and a 30-foot height limit. Residential front setbacks are generally 20 feet, while side and rear yards commonly range from 5 to 10 feet.
Wildfire access may be more restrictive than the underlying zoning, including a 30-foot building setback from property lines or road centers unless approved mitigation provides equivalent protection. Siskiyou County recommends consulting CAL FIRE before beginning a new home, and the current building page reports an average review time of 8–10 weeks for complete plan packages.
To move ahead, submit a property-information inquiry to Planning first, then take the confirmed zoning and fire requirements to Building at 530-841-2100.
Does Solano County, California Allow Modular Homes?
Yes! Solano County allows modular homes. Rural residential zoning includes RR-2.5, RR-5 and RR-10 districts, with the number generally reflecting the minimum parcel size in acres. A common rural-residential baseline is a 30-foot front setback, 20-foot side setbacks, a 25-foot rear setback and a 35-foot height limit, although water, sewer and parcel-specific zoning can alter these standards. This information applies only to unincorporated Solano County; property inside Benicia, Dixon, Fairfield, Rio Vista, Suisun City, Vacaville or Vallejo is regulated by that city.
Homeowners should note that Solano County issues the permits and inspects the foundation, onsite assembly, utilities and remaining construction for the modular home. The county may also require Environmental Health approval for a well or septic system and Public Works approval for grading, drainage or driveway access.
Homeowners should begin with the county’s parcel viewer and zoning FAQ, then submit through the online permit portal. Planning and Building & Safety can both be reached at 707-784-6765, and the county recommends confirming project-specific requirements before applying.
Does Sonoma County, California Allow Modular Homes?
It does! Modular construction is a legal option in Sonoma County when the finished home meets the same zoning standards as a site-built residence. In the R1 district, the standard minimum lot size is generally 6,000 square feet, with a 20-foot front setback, 5-foot interior side setbacks, a 20-foot rear setback, 40% maximum lot coverage and a 35-foot height limit. Rural Residential parcels may require 20,000 square feet in urban-designated areas, 1 acre with public water or 1.5 acres without public water.
Rural projects often need well or septic approval, while hillside and wildfire areas can trigger other requirements like geotechnical reports, fire-access improvements, and engineered grading. Building fees for new residential construction are generally tied to project valuation rather than one flat modular-home price.
To take the next step, you can use Permit Sonoma’s zoning search first, then follow its residential building-permit instructions so the factory plans and locally engineered foundation are reviewed as one coordinated project.
Does Stanislaus County, California Allow Modular Homes?
Yes! Stanislaus County permits a qualifying modular home wherever one detached single-family dwelling is allowed, including its R-1 and R-A districts. In R-1, front setbacks are measured from the road centerline: at least 40 feet along a minor street, 45 feet along a collector and 70 feet along a major street or expressway. The home must also remain at least 15 feet behind an adopted planned street line where applicable. Interior side and rear setbacks are 5 feet, maximum lot coverage is 50%, and dwelling height is limited to 35 feet.
Fees for a new residence depend on square footage, school and fire districts, and location-specific impact fees, so there is no single countywide total. The county publishes separate fee estimates for homes below and above 3,000 square feet. Start with Planning at 209-525-6330 to verify the zone and legal building site, then coordinate the construction permit with Building Permit Services at 209-525-6557.
Does Sutter County, California Allow Modular Homes?
A state-approved modular residence can be placed in Sutter County when the parcel permits a single-family home and satisfies the applicable development standards. In the R-1 district, newly created interior lots generally require 6,000 square feet, while corner lots require 7,500 square feet. Typical setbacks are 15 feet in front, 5 feet on an interior side, 10 feet along a street side and 20 feet in the rear, or 20% of the lot depth when that is less. A garage facing the street normally needs a 20-foot setback. These requirements cover only unincorporated Sutter County, not Yuba City or Live Oak.
Sutter County’s Building Services division reviews the foundation, onsite installation, structural connections and utilities. The department publishes a manufactured-home plan-submittal package, but owners of modular or factory-built housing should confirm that the project is being classified as an HCD factory-built residence rather than a HUD-code manufactured home.
Use the county’s parcel mapping to check zoning and FEMA flood information, then contact Development Services at 530-822-7400 before finalizing the home and foundation plans.
Does Tehama County, California Allow Modular Homes?
It is possible! Tehama County gives homeowners a direct path to install modular housing on land zoned for a single-family residence. In the R-1 district, the minimum lot size is 5,000 square feet with at least 60 feet of width. The primary home may cover up to 40% of the parcel and reach 2½ stories or 35 feet. The front yard is generally 20 feet from the property line or 50 feet from the roadway centerline, whichever controls, although road classifications and parcel dimensions can change the final building line. This guidance is for unincorporated Tehama County only; Red Bluff, Corning and Tehama administer their own permits.
Tehama publishes separate new- and used-manufactured-home applications, so a modular home buyer should clearly identify the unit as California factory-built housing and ask whether the standard new-house application is required.
Building permits can be filed through the county’s online portal. Verify zoning and setbacks with Planning at 530-527-2200, then coordinate the permit package with Building and Safety at 530-527-7002.
Does Trinity County, California Allow Modular Homes?
Yes, Trinity County allows modular homes as permanent dwellings where the parcel’s base zoning and any community-plan rules permit residential development. The county’s Single-Family Residential R-1 district uses a 6,000-square-foot minimum parcel size, while R-1A generally requires one-half acre. Rural Residential designations increase the minimum to 1, 2.5 or 5 acres. This section applies only to unincorporated Trinity County. If you live within a municipality, you can go directly to your local zoning department to find out more.
Planning reviews every building application for zoning compliance, while Building handles the foundation, installation and inspections. Environmental Health separately processes private well and septic approvals. The county’s application requires a site plan showing property lines, setbacks, roads, structures and utility systems; flood-overlay construction may first need a Floodplain Development Permit.
Take the parcel number and HCD factory-built plans to Community Development before commissioning the foundation design. Planning can be reached at 530-623-1351, and the county’s permits page provides the current building forms.
Does Tulare County, California Allow Modular Homes?
Tulare County can approve an HCD-compliant modular home as a primary residence when the property has residential rights under its zoning designation. Unlike counties with one simple R-1 table, Tulare relies on Ordinance No. 352, supplemental zoning maps and road-specific building lines. A common county road setback is 50 feet from the highway centerline, but numerous roads have their own established building lines, and the side and rear yards depend on the exact parcel zone. This information concerns unincorporated Tulare County only, rather than property inside cities such as Visalia, Tulare, Porterville or Dinuba.
A new residence requires a county building permit and must have adequate access, water, wastewater service and room for all required setbacks. Private wells and onsite septic systems need Environmental Health review, while foothill or mountain properties may require fire-access improvements and site-specific structural engineering.
The county advises homeowners to contact the Permit Center before purchasing plans because staff can identify zoning, utility and site requirements early. Applications are handled through the county’s online permitting system, and the Permit Center can be reached at 559-624-7100.
Does Tuolumne County, California Allow Modular Homes?
Yes. Tuolumne County treats an approved modular house as a permanent residential building rather than temporary housing. In the R-1 district, newly configured parcels generally need at least 7,500 square feet and 50 feet of width at the front setback line. Estate Residential districts step up to minimum parcel sizes of 1, 2, 3, 5 or 10 acres. Residential buildings in R-1, R-2 and the RE districts are ordinarily limited to 40 feet in height. This summary applies to unincorporated Tuolumne County and not incorporated Sonora, so homeowners there will need to go directly to their local zoning departments for more information.
Mountain conditions make the parcel lookup especially important here. Tuolumne County’s Building Viewer identifies the zoning, elevation, climate zone and the assigned snow-load value, allowing the foundation and roof system to be engineered for the actual site. Homeowners can also upload the state-approved modular plans, installation documents and locally engineered foundation through OpenGov only after checking the Building Viewer.
For more questions and next steps, Building and Safety answers project questions at 209-533-5637.
Does Ventura County, California Allow Modular Homes?
Yes, Ventura County permits modular homes on land where the applicable coastal or non-coastal zoning ordinance allows a dwelling. The county’s non-coastal R-1 zone is intended for single-family residential development, but the minimum lot size and dimensional standards can vary with the zone suffix and area plan. Development tables commonly use a 20-foot front setback and 5-foot interior side setback, while the rear yard and allowable coverage depend on the particular district.
Before a building permit is issued, Planning generally confirms zoning clearance and Building and Safety reviews the foundation, structural installation and utilities. Properties with septic systems need Environmental Health approval, and grading in a special flood-hazard area requires floodplain clearance or a floodplain permit.
The county’s “What’s My Zoning” tool accepts an APN and identifies whether the property is governed by the coastal or non-coastal code. Permit documents can then be filed and tracked through VC Citizen Access; Planning can be reached at 805-654-2488 and Building and Safety at 805-654-2771.
Remember that this guidance applies to unincorporated Ventura County; homeowners within municipalities can go directly to their local zoning departments to find out the regulations.
Does Yolo County, California Allow Modular Homes?
It definitely does! Like the rest of CA, Yolo County allows factory-built modular residences in single-family zoning districts. In the Rural Residential RR-5 and RR-2 zones, the minimum parcel sizes are 5 and 2 acres. Both use a 20-foot setback from the property line or 50 feet from the roadway centerline, whichever is greater, with 10-foot side setbacks, a 25-foot rear setback and a 35-foot residential height limit. The R-L zone allows smaller serviced lots, using a 10-foot front setback, 20 feet for a street-facing garage, 5-foot sides and a 20-foot rear yard. This information is limited to unincorporated Yolo County.
Parcels without public water or wastewater service generally need at least 2 acres for a new building permit. Additional restrictions include 30-foot front yards along major arterials, controls near levees, and a general 100-foot setback from streams unless the lot makes it infeasible.
After confirming the parcel through the county zoning maps, homeowners should submit the state-approved modular plans with the foundation, site, utility and energy documents to Building Inspection Services. Private well and septic questions should be cleared with Environmental Health at 530-666-8646 before the home is ordered.
Does Yuba County, California Allow Modular Homes?
Yes, Yuba County’s residential districts allow permanent homes built with state-approved modular construction. In the Residential Single-Family RS zone, newly created parcels generally require 4,500 square feet and 50 feet of width. The home can reach 30 feet in height, with 5-foot interior sides and a 15-foot rear setback. In Residential Estate zoning, the minimum lot is 21,000 square feet with 80 feet of width, 10-foot side setbacks, a 25-foot rear setback and a 35-foot height limit. Front setbacks are measured from the sidewalk, ultimate road right-of-way or drainage ditch rather than one universal property-line distance. These standards apply only within unincorporated Yuba County, not Marysville or Wheatland.
Yuba County requires every legal dwelling to be placed on a foundation and meet residential building standards so a RV or home on wheels cannot be used as a permanent residence outside an approved park.
To take the next step, you can bring the parcel number and HCD documents to Planning before designing the site plan. They will get you started on the process.
Looking for a Modular Home Builder Serving California?
Ready to take the next step toward owning a quality modular home that fits your needs? Zook Cabins is excited to let you know we work with homeowners in California, no matter where you live. Our decades of experience equip us to help you choose the right modular home, then our expert team will handle the hard lifting, from delivery details to financing insights.
Call today to learn more or request a free quote on your favorite modular home. We would love to help you dwell beyond the ordinary.
Frequently Asked Questions about Modular Homes in California:
What Kind of Foundation Does A Modular Home Need in California?
Modular homes require a permanent foundation, such as a crawlspace, basement, or pier and beam foundation. This ensures a secure home that holds up as well as a stick-built home. Before the home is delivered, the foundation is inspected to ensure it is properly constructed and ready for the modular sections to be permanently secured in place.
Learn more about foundation types in our foundations guide!
Can Modular Homes Be Used As ADUs?
Yes, there are modular ADUs and modular cabins that could be used as ADUs if small enough. Accessory dwelling units are designed to be an additional structure on the same lot as a primary dwelling, not be the main residence. They are very popular in California and offer affordable living options.
The biggest requirement for ADUs is the size restraint, so the modular home you choose needs to fit with California’s size requirements for ADUs. A model like the Lariat or the A-Frame Retreat would be ideal accessory dwelling units.
To learn about ADU requirements in California, we have compiled all the helpful information you need in one concise guide!
Does California Require Land to Already Be Owned Before Buying a Modular Home?
While you don’t need to have land purchased before placing an order for a modular home, you will need to have a property you own before the home can be permitted and installed.
Because zoning laws and last minute changes can bring unwanted surprises, we recommend having a purchased piece of land that is buildable before placing a large modular home order.
Our financing team is happy to walk you through more specifics for your California area if you would like. Simply contact us so our Financing Manager can help you out!
What Utility Hookups Are Required for a Modular Home in California?
Each modular home from Zook Cabins comes with all the utility rough-ins and simply need to be hooked up. This includes electric, septic, and water hookups. As a part of the process your GC will be able to help you figure out how our connections need to be made, to meet your specific requirements.
What are Modular Homes and Are They Allowed in California?
Modular homes are homes that are constructed to the International Residence Code (IRC) in conjunction with your local building code. These homes are built offsite in modules, and then delivered and installed on a permanent foundation on your property. The biggest advantage to a modular home is that they offer faster build time then on site, have less waste in materials allowing them to be eco friendly and reasonably priced.
And the best news for California residents? Modular homes are allowed and welcomed in California! Within the state, modular homes are often referred to as factory-built housing (FBH). The home should have Department of Housing and Community Development (HCD) approved plans and a HCD Insignia of Approval on each approved model.
Modular homes have been around for years and the quality has only improved over time. And more good news? Today’s modular homes hold the same resale value as traditional homes making your purchase not only a great purchase but quality investment.
What is the Difference Between a Modular Home & a HUD Home?
In the housing world, terms can get tricky or even used interchangeably without realising the significant difference. You may have heard terms like HUD homes and modular homes and wondered, “Isn’t that just 2 different words being used for the same thing?”
As explained above, a modular home is built to IRC standards offsite then delivered and installed on a permanent foundation. Modular homes are not movable and will increase in value just like a traditional stick-built home.
In contrast, HUD homes, or manufactured homes as they are often called, are federally regulated and built to the Manufactured Construction Safety Act Standards of 1974. HUD homes are attached to a steel chassis and installed on a concrete slab, making them secure, but still movable. At Zook Cabins, we call these luxury mobile homes.
However, with the recent changes in The 21st Road to Housing Act manufactured homes are now able to be taken off of their steel chassis and
To help you understand the major differences take a look at our article Modular Homes Vs. Manufactured Homes for a comprehensive view of differences.
How Close Can a Modular Home Be to Property Lines?
That depends on your zoning district. Each parcel is zoned differently and will therefore have varying requirements. Modular homes are zoned like traditional homes and will follow the same setback requirements.
For example, in Los Angeles County’s R-1 (single-family residential) zone, front yard setbacks are 20 feet, side yards 5 feet, and rear yards 15 feet, with height capped around 35 feet depending on the area plan or overlay. If you wanted to place a modular home in this zone, it would need to meet those same criteria.
Do You Need A Permit For A Modular Home in California?
Yes, you will need a building permit along with multiple permits for electrical, septic, HVAC, and potentially more depending on your county.
Modular homes in California follow a two-track permitting process. First, the manufacturer (in this case Zook Cabins) secures state approval from the Housing Department which reviews plans and inspects each factory-built module, which then leaves the factory bearing an HCD insignia confirming it meets state code. Then, once the homes arrive on-site, the county building department will inspect and approve the foundation systems in place, utility hookups, and site work. Once these local approvals have been met and a certificate of occupancy is given, homeowners are able to move into their new home.
Costs and timelines vary significantly by jurisdiction. Local permit fees typically run $5,000–$20,000 depending on county and utility hookup needs. Because most plan review happens at the state level before local submittal, local permitting timelines for modular projects tend to be shorter and more predictable than for fully site-built homes.
What Sizes of Modular Homes Does Zook Cabins Offer?
Zook Cabins has a wide lineup of beautiful modular homes for you to choose.
Our smaller modular models start at approximately 470 square feet, providing a comfortable one-bedroom home for individuals or vacation-property owners. From there, you can choose from numerous floor plans ranging from roughly 660 to 2,900 square feet, with one to four bedrooms and several bathroom configurations.
For families who need even more room, larger models such as the Canyon Lodge offer as much as 2,926 square feet of finished living space. These spacious homes include multiple bedrooms, open-concept living areas, primary-bedroom suites, lofts and additional bathrooms.
Whether you need a compact retirement home, a comfortable family residence or a large cabin for entertaining guests, Zook Cabins offers options ranging from cozy single-section homes to spacious multi-section designs.
Here are several examples:
| Zook Cabins model | Finished size | Bedrooms | Bathrooms |
| A-Frame Retreat | 470 sq. ft. | 1 | 1 |
| The Woodland | 738-1,442 sq. ft. | 2-3 | 1-2 |
| The Walden Stack | 1,290 sq. ft. | 3 | 3 |
| The Canyon Lodge | Up to 2,296 sq. ft. | Up to 4 | Up to 2.5 |
| The Two Pines | 935-1,269 sq. ft. | 2-3 | 2 |
What Features are Included in a Modular Home from Zook Cabins?
When you buy a modular house from Zook Cabins, you’re investing in a home to create memories, build community, and enjoy modern comforts. Each home is delivered with a completed structural shell and is fully insulated, wired and plumbed to meet all state and local building codes.
For an example of what else our homes include, here’s some features from our gorgeous A-frame retreat home:
- Cathedral ceilings in the whole cabin.
- Primed and painted cabinet-grade Birch Plywood on all walls and ceiling surfaces
- Luxury Vinyl Plank Flooring Throughout.
- Craftsman Style Interior Doors.
- Recessed Lights Throughout.
- Shaker Style Painted Kitchen Cabinets
- Quartz Countertops
- Space for 24” x 61” Fridge
- Space for 24” x 14” Microwave.
- 48” Shower with Fiberglass base, Fibo Shower surround, and Glass Shower door.
- 48” Custom Vanity with Black sink
- 60” Freestanding soaking tub with wall-mounted fill spout.
Modular homes from Zook Cabins have intentionally designed layouts for maximum efficiency and comfort. Added features like porches, fireplaces, and more work together to create a peaceful retreat for you and your family’s needs.
Does Zook Cabins Have Modular Homes with Multiple Bedrooms and Bathrooms?
We definitely do! There is a huge range of options, including the number of bedrooms and bathrooms. Check out this beautiful two bedroom, two bathroom home if that fits your sizing needs.
Need more space? Here’s our Woodland home, with 3 bedrooms. Or our cozy Spruce model with just one bedroom and bathroom. Don’t limit yourself, you have options!
Can A Modular Home from Zook Cabins be Customized?
At Zook Cabins all of our modular homes offer personalization options available for you. From choosing various layout options within the style you like or choosing the exterior color of the home or kitchen components.
Interested in learning more? Call our team today and we’re happy to answer whatever questions you might have!
Do Modular Homes Have Good Resale in California?
Definitely! Modular homes hold their value at the same rate as traditional stick-built homes . These days, Fannie Mae gives modular homes the same lending treatment as site-built homes, and appraisers use comparable local home sales rather than automatically discounting the property because it was factory-built.
For context, California homes sold for a median $782,221 in May 2026, up 2.3% from the previous year. At that same rate, a modular home and land valued at $600,000 would increase by approximately $13,800 in one year, reaching $613,800; at an average 3% annual increase, it would be worth about $695,600 after five years.
Of course, factors like location and quality of the home play into the resale discussion. But currently, California homeowners can make smart financial decisions by investing in modular homes. Request a quote today to start your smart investment!
Conclusion…
California’s modular home requirements may feel complicated, but the process becomes much easier when you have a team who thoroughly understands the entire process, from zoning laws and permits to delivery and installation.
At Zook Cabins, we help homeowners choose high-quality modular homes built for comfortable long-term living. Our team can help you explore available floor plans, understand the delivery process, and prepare for the next steps toward placing a modular home on your California property. Contact Zook Cabins today to begin planning a home that works for you.