Union City · Building on your lot

Building on your lot in Union City

Union City sets its own limits on fences in residential districts and bans some home businesses. Fence height depends on the yard and on what the lot abuts.

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Key points

Fence height: Union City residential fences: 3 feet in front yards; 6 feet, plus up to 1.5 feet of lattice, in rear and interior side yards.
Banned businesses: Union City does not allow home businesses such as clinics, hospitals, barber shops, beauty parlors, tea rooms, animal hospitals and kennels.

Each rule below is marked Union City code or CA state law and links to the section it comes from (checked October 2026). General information, not legal advice.

Fences and walls

Union City code Union City residential fences: 3 feet in front yards; 6 feet, plus up to 1.5 feet of lattice, in rear and interior side yards.

All 5 Union City rules on fences and walls, with the code text →

Running a business from home

Union City code What Union City's code adds
Businesses not allowed	Clinics, hospitals, barber shops, beauty parlors, tea rooms, tourist homes, animal hospitals and kennels § 18.08.280 · code text Clinics, hospitals, barber shops, beauty parlors, tea rooms, tourist homes, animal hospitals and kennels, among others, are not home occupations.

Lot splits under SB 9

Union City code One of the 2 new parcels may not be smaller than 40% of the original lot area. No single unit may be larger than 2,000 square feet.

All 14 Union City rules on lot splits under SB 9, with the code text →

RV and boat parking

Union City code What Union City's code adds
Size limit	Vehicles over 20 feet long or 10,000 pounds or more may not park on any street at any time. Applies: Except in areas the City Council designates by resolution. § 10.36.195 · code text Vehicles having a length in excess of twenty feet and/or having a manufacturer's gross vehicle weight rating of ten thousand pounds or more shall not stop, stand or park on any highway, street or alley at any time except in areas designated by the City Council by resolution.
Parking on the street	Allowed only while actively loading and unloading. Applies: Applies to vehicles over 20 feet long or 10,000 pounds or more. § 10.36.195 · code text It is not a violation of this chapter to park said vehicles when such vehicles are:

Solar panels and EV chargers

Union City code What Union City's code adds
EV charger permit	Permits issue when the application meets the City checklist; no use until inspection and approval by City and utility. Applies: Applies to EV charging station permit approval; utility approval only as necessary. § 15.88.040 · code text Application approval/permit issuance does not authorize an applicant to energize or utilize the electric vehicle charging station, unless and until an inspection is performed and approval is granted by the City and the utility carrier as necessary.
Solar permit process	Administrative approval and all required permits once the checklist is confirmed; only 1 inspection is required. Applies: Applies to small residential rooftop energy systems eligible for expedited review. § 15.78.070 · code text Upon confirmation by the Building Official of the application and supporting documentation being complete and meeting the requirements of the California Solar Permitting Guidebook checklist, the Building Official shall administratively approve the application and issue all required permits or authorizations.

Tree removal

Union City code What Union City's code adds
Permit to remove	Yes; removal needs site development review, a use permit or Director approval. Applies: Applies to live trees 6 inches or more across at the base in the Open Space (OS) zone. § 18.92.150 · code text Removal of live trees of six inches or more in diameter at the base, shall be prohibited, except with the granting of site development review, use permit or approval of Director as applicable.
Protected trees	Live trees 6 inches or more in diameter at the base. Applies: Applies to properties in the Open Space (OS) zoning district. § 18.92.150 · code text Removal of live trees of six inches or more in diameter at the base, shall be prohibited, except with the granting of site development review, use permit or approval of Director as applicable.

Grading and erosion control

Union City code Up to 50 cubic yards disturbed, stored or used as fill, with no off-site hauling or blocked drainage. Up to 5 cubic yards disturbed, stored, disposed of or used as fill.

All 4 Union City rules on grading and erosion control, with the code text →

Building on a hillside

Union City code No artificial slope steeper than nearby natural slopes or 3:1, whichever is greater. Grading should generally stay within the building footprint, under access roads and driveways, or where needed for landslides.

All 4 Union City rules on building on a hillside, with the code text →

Park and impact fees for new homes

Union City code What Union City's code adds
Exemptions	Homes lawfully in place before the parcel or final map is filed are not new units. Applies: Park land dedication or fee for subdivisions. § 17.30.040 · code text The term "new dwelling unit" does not include dwelling units lawfully in place prior to the date on which the parcel or final map is filed.
How the park fee is set	Fair market value of the required land plus 20% toward off-site improvement costs. Applies: Park fee paid by subdividers instead of land. § 17.30.070 · code text When a fee is to be paid in lieu of land dedication, value of the amount of such fee shall be based upon the fair market value of the amount of land which would otherwise be required for dedication pursuant to Section 17.30.040, plus twenty percent toward costs of off-site improvements, such as extension of utility lines.
Parkland per 1,000 residents	3 acres per 1,000 residents. § 17.30.030 · code text It is found and determined that the public interest, convenience, health, welfare and safety require that three acres of property for each one thousand persons residing within this City be devoted to neighborhood and community park and recreation purposes.
When the fee applies	50 parcels or fewer: the subdivider pays land value plus 20% instead of land; voluntary dedication may be accepted. § 17.30.050 · code text If the proposed subdivision contains fifty parcels or less, the subdivider shall pay a fee equal to the land value, plus twenty percent toward costs of off-site improvements, of the portion of the local park required to serve the needs of the residents of the proposed subdivision as prescribed in Section 17.30.040 and in an amount determined in accordance with the provisions of Section 17.30.070.

Noise and construction hours

Union City code 8 a.m. to 8 p.m. 9 a.m. to 8 p.m.

All 4 Union City rules on noise and construction hours, with the code text →

Family child care homes

CA state law California law
Zoning	A small or large family child care home is a residential use and a use by right under all local ordinances, including zoning Health & Safety Code § 1597.45(a)
Business license or fee	A city or county may not charge a business license, fee or tax to run a family child care home Health & Safety Code § 1597.45(b)
Local rules	Local limits on height, setbacks, lot size, health and safety must be the same as for every other home in the same zone Health & Safety Code § 1597.45(e)
Small home	Up to eight children, counting the provider's own children under 10 who live there Health & Safety Code § 1596.78(c)
Large home	7 to 14 children, counting the provider's own children under 10 who live there Health & Safety Code § 1596.78(b)

Home alarm permits and false alarms

Union City code Automatic shut-off within 15 minutes after activation. An alarm may not ring longer than 1 hour.

All 4 Union City rules on home alarm permits and false alarms, with the code text →

Signs on homes

Union City code allowed, up to one and one-half (1-1/2) square feet At most 1 sign.

All 14 Union City rules on signs on homes, with the code text →

Trash and recycling carts

Union City code Separate organic waste and place it in containers provided by the solid waste or recycling franchisee. Before midnight on the day they are emptied.

All 4 Union City rules on trash and recycling carts, with the code text →

Historic homes

Union City code At least 45 years old. The deciding body recommends approval only if the listed findings are met.

All 4 Union City rules on historic homes, with the code text →

Other Union City rules on this

Union City's code also has these chapters. We have not summarized their values on this page yet; read them in the library.

Permit to keep more dogs (§ 8.22.020)
Building in a flood hazard area (Ch. 18.98)

Who this affects

HomeownersContractorsDesigners

Frequently asked questions

Can I run a business from my home in Union City?

Union City does not allow home businesses such as clinics, hospitals, barber shops, beauty parlors, tea rooms, animal hospitals and kennels.

Can I park an RV or boat at my home in Union City?

Union City's code: Vehicles over 20 feet long or 10,000 pounds or more may not park on any street at any time. (Except in areas the City Council designates by resolution.) (§ 10.36.195).

Do I need a permit for solar panels or an EV charger in Union City?

Union City's code: Administrative approval and all required permits once the checklist is confirmed; only 1 inspection is required. (Applies to small residential rooftop energy systems eligible for expedited review.) (§ 15.78.070); Permits issue when the application meets the City checklist; no use until inspection and approval by City and utility. (Applies to EV charging station permit approval; utility approval only as necessary.) (§ 15.88.040).

Do I need a permit to remove a tree in Union City?

Union City's code: Yes; removal needs site development review, a use permit or Director approval. (Applies to live trees 6 inches or more across at the base in the Open Space (OS) zone.) (§ 18.92.150); Live trees 6 inches or more in diameter at the base. (Applies to properties in the Open Space (OS) zoning district.) (§ 18.92.150).

What park or impact fees apply to a new home in Union City?

Union City's code: Fair market value of the required land plus 20% toward off-site improvement costs. (Park fee paid by subdividers instead of land.) (§ 17.30.070); 3 acres per 1,000 residents. (§ 17.30.030).

Can I run a family child care home in Union City?

California law sets this for every city, including Union City: Zoning: A small or large family child care home is a residential use and a use by right under all local ordinances, including zoning (Health & Safety Code § 1597.45(a)); Business license or fee: A city or county may not charge a business license, fee or tax to run a family child care home (Health & Safety Code § 1597.45(b)); Local rules: Local limits on height, setbacks, lot size, health and safety must be the same as for every other home in the same zone (Health & Safety Code § 1597.45(e)); Small home: Up to eight children, counting the provider's own children under 10 who live there (Health & Safety Code § 1596.78(c)); Large home: 7 to 14 children, counting the provider's own children under 10 who live there (Health & Safety Code § 1596.78(b)).

General information, not legal advice.

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