Do I need a permit to build a deck in Antioch, CA?

Yes, in most cases you need a building permit to build a deck in Antioch. Attached decks, elevated decks (those more than 30 inches above grade), and decks over 200 square feet typically require a permit and a site plan showing the deck's location relative to property lines, the house, and any easements. The site plan must demonstrate that the deck meets the required setbacks for your zoning district, which for standard R-1 zones is typically 5 feet from the side and rear property lines. Permits are reviewed by the Antioch Building Division, and simple deck projects can sometimes receive over-the-counter approval within a few business days if plans are complete and code-compliant.

Do I need a permit for a shed in Antioch, California?

In Antioch, detached accessory structures like sheds generally require a building permit if they exceed 120 square feet in floor area. Smaller sheds may be exempt from a building permit but could still be subject to zoning rules regarding placement, setbacks, and lot coverage. If your property is in a FEMA Special Flood Hazard Area, even a small shed may require a floodplain development permit. Your site plan must show the shed's location, its distance from all property lines, and its relationship to the primary dwelling. Always confirm requirements with the Antioch Community Development Department before starting construction, since HOA rules in some neighborhoods may also apply.

What are the setback requirements for residential properties in Antioch?

For standard single-family (R-1) zones in Antioch, typical setback requirements are 20 feet for the front yard, 5 feet for each side yard (with a 10-foot street-side setback on corner lots), and 20 feet for the rear yard for the primary dwelling. Accessory structures like detached garages and sheds are often allowed within 5 feet of the side and rear property lines. Accessory Dwelling Units (ADUs) benefit from California state law, which limits setback requirements to 4 feet from the rear and side property lines. Setbacks can vary significantly in planned unit developments and other special zoning districts, so always verify your specific parcel's requirements with the city.

How much does a building permit cost in Antioch, CA?

Building permit fees in Antioch are calculated based on the estimated valuation of the construction work. The city uses a fee schedule that applies a base permit fee plus a plan check fee, which is typically around 65 percent of the building permit fee for projects requiring plan review. For a modest room addition valued at around $50,000, total permit and plan check fees might range from $800 to $2,000 or more, depending on current city fee schedules. ADU permits may have reduced fees under California state law for certain affordable ADUs. For an accurate estimate, contact the Antioch Building Division directly or review the current fee schedule on the city's website before submitting your application.

Can I draw my own site plan for a permit in Antioch, or do I need a licensed professional?

For most straightforward residential projects in Antioch, you are not required to hire a licensed architect, engineer, or surveyor to prepare a site plan. Homeowners and contractors can draw their own site plans as long as the plans are drawn to scale, include all required information (property dimensions, structure locations, setbacks, north arrow, scale bar, and relevant site features), and are legible. However, for complex projects such as major structural additions, hillside construction, or projects in flood zones, the city may require plans stamped by a licensed engineer or architect. Using an online tool like Site Plan Creator can help ensure your site plan meets Antioch's formatting and content requirements without the cost of hiring a professional drafter.

What needs to be included on a residential site plan in Antioch?

Antioch's Building Division requires a site plan to include the following elements for most residential permit applications: the property's legal dimensions and lot boundaries, the location and footprint of all existing structures on the lot, the location and footprint of the proposed new construction or improvement, dimensioned setbacks from all property lines to existing and proposed structures, any recorded easements on the property, the location of driveways and access points, a north arrow, a scale bar or written scale, and the property address. For projects in flood zones, you may also need to show base flood elevation data. For ADUs, the site plan should indicate utility connections and any required fire department access.

Where do I submit my site plan and permit application in Antioch?

As of 2026, Antioch accepts permit applications both online and in person. The city's online permitting portal, accessible through the Antioch Community Development Department website at antiochca.gov, allows applicants to upload plans, submit forms, pay fees, and track review status without visiting City Hall. In-person submissions are accepted at the Building Division counter located at Antioch City Hall, 200 H Street, Antioch, CA 94509. Counter hours are generally Monday through Thursday; check the city's website for current hours since schedules can change. For large or complex projects, calling the Building Division in advance to confirm submittal requirements can save time.

What happens if I build without a permit in Antioch?

Building without a required permit in Antioch can have serious consequences. The city's Building Division has the authority to issue a stop-work order requiring all construction to halt immediately. You may be required to obtain a retroactive permit, which often involves additional plan check fees (sometimes double the standard fee), and an inspector may require portions of unpermitted work to be exposed or demolished so that structural and safety elements can be inspected. Unpermitted work can also create problems when you try to sell your home, as lenders and buyers may require the work to be legalized or removed. In some cases, the city can pursue code enforcement action, resulting in fines and liens on the property.

What are the ADU rules in Antioch, CA?

Antioch allows ADUs and Junior ADUs (JADUs) on single-family and multifamily residential lots in accordance with California state law. State law significantly limits the city's ability to impose restrictions, meaning ADUs can generally be built up to 850 square feet for a one-bedroom unit and 1,000 square feet for a two-bedroom unit (or up to 50 percent of the primary dwelling's size for attached ADUs). Setbacks are limited to 4 feet from rear and side property lines for detached ADUs. Owner-occupancy requirements for ADUs have been suspended through at least 2025 under state law. Antioch must act on a complete ADU permit application within 60 days. Impact fees may be waived for ADUs under 750 square feet. A site plan showing the ADU location, setbacks, and utility connections is required.

Site Plan Requirements in Antioch, CA (Permit Guide)

By Site Plan Creator Team • May 26, 2026

Antioch, California homeowners planning any residential improvement project need to understand local site plan and permit requirements before breaking ground. This guide covers everything from typical permit triggers and setback rules to where and how to submit your application in Antioch.

Site plan requirements for residential properties in Antioch, California

Residential Site Plans and Building Permits in Antioch, CA

Antioch is one of the fastest-growing cities in Contra Costa County, and with that growth comes an active residential construction and renovation scene. Whether you are adding an accessory dwelling unit (ADU) to cash in on the Bay Area housing demand, building a backyard deck, or putting up a new fence, the City of Antioch requires a properly prepared site plan as part of nearly every building permit application. Understanding what the city expects before you submit can save you weeks of back-and-forth with the Building Division and help your project move forward without costly delays.

What Is a Residential Site Plan and Why Does Antioch Require One?

A residential site plan is a scaled, bird's-eye drawing of your property that shows the lot boundaries, existing structures, proposed construction, setbacks from property lines, driveways, easements, and any other features relevant to your project. Antioch's Building Division uses the site plan to verify that your proposed work complies with the city's zoning ordinance, the California Building Code (CBC), and any applicable Contra Costa County or state regulations.

Without an accurate site plan, plan checkers cannot confirm that your addition stays within required setbacks, that your new shed does not encroach on a utility easement, or that your ADU meets state density bonus law requirements. Submitting an incomplete or inaccurate site plan is one of the top reasons permit applications are rejected or placed on hold in Antioch.

Common Residential Projects That Require a Permit in Antioch

The following project types almost always require a building permit and a site plan in Antioch:

Room additions and home expansions: Any addition that increases the footprint or living area of a home requires a permit, structural drawings, and a site plan showing setbacks and lot coverage.
Accessory Dwelling Units (ADUs) and Junior ADUs: California state law (AB 68, SB 9, and related legislation) has streamlined ADU approvals, but Antioch still requires a permit, site plan, and compliance with utility connection requirements.
Detached garages and large sheds: Structures over 120 square feet typically require a permit. Even smaller sheds may need one if they are attached to another structure or located in a flood zone.
Decks and patios: Attached decks, elevated decks, or any deck exceeding 200 square feet generally require a permit and site plan.
Swimming pools and spas: In-ground pools and permanent above-ground spas require a permit, barrier/fencing documentation, and a site plan.
Fences: Fences over 6 feet in height require a permit. Front-yard fences over 3.5 feet may also be subject to zoning review.
Driveways and impervious surfaces: New or significantly expanded driveways may require a grading or encroachment permit, especially if they connect to a public street or affect stormwater drainage.
Solar panels and battery storage systems: Required under the California Energy Code for new construction and common for retrofits; a permit and roof plan (which functions similarly to a site plan) are required.

Local Zoning Considerations and Quirks in Antioch

Antioch's zoning landscape has several features that homeowners should be aware of before starting a project:

Flood Zone Exposure: Portions of Antioch near the San Joaquin River Delta and Marsh Creek are located within FEMA-designated Special Flood Hazard Areas (SFHAs). If your property falls within a flood zone, your project may require elevation certificates, floodplain development permits, and additional site plan details showing base flood elevations. You can check your property's flood zone status using the FEMA Flood Map Service Center.

HOA Restrictions: Many neighborhoods in Antioch, particularly newer master-planned communities in the Hillcrest and Prewett Ranch areas, are governed by homeowners associations (HOAs). HOA approval is separate from city permit approval and may impose stricter design standards, material requirements, or setback rules than the city's zoning code.

Wildfire Hazard Severity Zones: Parts of eastern Antioch near the Contra Costa hills fall within or adjacent to State Responsibility Areas (SRAs) or Local Responsibility Areas (LRAs) with elevated fire risk. Projects in these zones may need to comply with California's Chapter 7A building standards, which require fire-resistant materials and ember-resistant vents.

Stormwater and Impervious Surface Limits: Antioch participates in the Contra Costa Clean Water Program. Projects that add significant impervious surface may trigger C.3 stormwater requirements, meaning you may need to incorporate Low Impact Development (LID) measures and document them on your site plan.

Typical Residential Setback Requirements in Antioch

Setbacks in Antioch vary by zoning district, but the following ranges are typical for standard single-family residential (R-1) zones:

Front yard setback: 20 feet (measured from the front property line to the nearest structure)
Side yard setback: 5 feet minimum on each side (corner lots may have a 10-foot street-side setback)
Rear yard setback: 20 feet for the primary dwelling; ADUs may be allowed as close as 4 feet to the rear and side property lines under California state law
Accessory structures (sheds, detached garages): Often 5 feet from side and rear property lines, though some zones allow closer placement

Always verify setbacks for your specific parcel and zoning designation with the Antioch Community Development Department, as planned unit developments (PUDs) and other special districts may have different standards.

How to Submit a Permit Application in Antioch

Antioch's Building Division handles residential permit applications through the city's Community Development Department. As of 2026, the city accepts both in-person and online permit submittals.

Online Submissions: Antioch uses an online permitting portal where applicants can submit applications, upload plans, pay fees, and track review status. Visit the City of Antioch Community Development Department for portal access and current submittal requirements.

In-Person Submissions: The Building Division is located at Antioch City Hall, 200 H Street, Antioch, CA 94509. Counter hours are typically Monday through Thursday; check the city website for current hours as they may vary.

Plan Review Timelines: Simple projects (fences, small sheds, water heaters) may qualify for over-the-counter approval in one to three business days. Standard residential permits, including room additions and pool permits, typically take three to six weeks for initial plan review. ADU applications processed under California's streamlined review law must receive a determination within 60 days of a complete application submittal. Complex projects or those requiring multiple department sign-offs may take longer.

Fees: Permit fees in Antioch are based on the valuation of the work. Plan check fees are typically assessed as a percentage of the building permit fee. Contact the Building Division or use the city's fee schedule for a current estimate.

Common Reasons Permit Applications Are Rejected in Antioch

Missing or inaccurate site plan: The site plan does not show all required elements, such as property dimensions, existing structures, proposed work, or setback dimensions.
Incorrect scale: The drawing is not drawn to a recognizable engineering or architectural scale, making it impossible for plan checkers to verify dimensions.
Setback violations: The proposed structure is shown too close to a property line, easement, or another structure.
Incomplete application: Required forms, owner authorization, contractor license information, or energy compliance documents are missing.
Zoning conflicts: The proposed use or structure type is not permitted in the property's zoning district.
Flood zone non-compliance: Projects in FEMA flood zones lack required elevation data or floodplain development documentation.
Missing Title 24 energy compliance: California requires energy compliance documentation for most new construction and additions.

Get Started with Site Plan Creator

Preparing an accurate, professional-quality site plan does not have to be complicated or expensive. Site Plan Creator makes it easy for Antioch homeowners, contractors, and investors to generate permit-ready residential site plans online, without hiring a surveyor or draftsperson for straightforward projects. Simply enter your property details, place your structures, and export a scaled site plan that meets Antioch Building Division requirements. Start your project on the right foot and avoid the most common rejection reasons by using Site Plan Creator before you submit.

For additional guidance on California building codes, visit the California Building Standards Commission.

Frequently Asked Questions

Do I need a permit to build a deck in Antioch, CA?: Yes, in most cases you need a building permit to build a deck in Antioch. Attached decks, elevated decks (those more than 30 inches above grade), and decks over 200 square feet typically require a permit and a site plan showing the deck's location relative to property lines, the house, and any easements. The site plan must demonstrate that the deck meets the required setbacks for your zoning district, which for standard R-1 zones is typically 5 feet from the side and rear property lines. Permits are reviewed by the Antioch Building Division, and simple deck projects can sometimes receive over-the-counter approval within a few business days if plans are complete and code-compliant.
Do I need a permit for a shed in Antioch, California?: In Antioch, detached accessory structures like sheds generally require a building permit if they exceed 120 square feet in floor area. Smaller sheds may be exempt from a building permit but could still be subject to zoning rules regarding placement, setbacks, and lot coverage. If your property is in a FEMA Special Flood Hazard Area, even a small shed may require a floodplain development permit. Your site plan must show the shed's location, its distance from all property lines, and its relationship to the primary dwelling. Always confirm requirements with the Antioch Community Development Department before starting construction, since HOA rules in some neighborhoods may also apply.
What are the setback requirements for residential properties in Antioch?: For standard single-family (R-1) zones in Antioch, typical setback requirements are 20 feet for the front yard, 5 feet for each side yard (with a 10-foot street-side setback on corner lots), and 20 feet for the rear yard for the primary dwelling. Accessory structures like detached garages and sheds are often allowed within 5 feet of the side and rear property lines. Accessory Dwelling Units (ADUs) benefit from California state law, which limits setback requirements to 4 feet from the rear and side property lines. Setbacks can vary significantly in planned unit developments and other special zoning districts, so always verify your specific parcel's requirements with the city.
How long does it take to get a building permit approved in Antioch?: Permit approval timelines in Antioch depend on the complexity of the project. Simple permits such as water heaters, fences, or small sheds may qualify for over-the-counter approval in one to three business days when all documents are in order. Standard residential projects like room additions, pools, or detached garages typically take three to six weeks for initial plan review. ADU applications are subject to California's streamlined review law, which requires the city to issue a determination within 60 days of receiving a complete application. Submitting a complete, accurate site plan and all required documents with your initial application is the best way to avoid delays and correction cycles.
How much does a building permit cost in Antioch, CA?: Building permit fees in Antioch are calculated based on the estimated valuation of the construction work. The city uses a fee schedule that applies a base permit fee plus a plan check fee, which is typically around 65 percent of the building permit fee for projects requiring plan review. For a modest room addition valued at around $50,000, total permit and plan check fees might range from $800 to $2,000 or more, depending on current city fee schedules. ADU permits may have reduced fees under California state law for certain affordable ADUs. For an accurate estimate, contact the Antioch Building Division directly or review the current fee schedule on the city's website before submitting your application.
Can I draw my own site plan for a permit in Antioch, or do I need a licensed professional?: For most straightforward residential projects in Antioch, you are not required to hire a licensed architect, engineer, or surveyor to prepare a site plan. Homeowners and contractors can draw their own site plans as long as the plans are drawn to scale, include all required information (property dimensions, structure locations, setbacks, north arrow, scale bar, and relevant site features), and are legible. However, for complex projects such as major structural additions, hillside construction, or projects in flood zones, the city may require plans stamped by a licensed engineer or architect. Using an online tool like Site Plan Creator can help ensure your site plan meets Antioch's formatting and content requirements without the cost of hiring a professional drafter.
What needs to be included on a residential site plan in Antioch?: Antioch's Building Division requires a site plan to include the following elements for most residential permit applications: the property's legal dimensions and lot boundaries, the location and footprint of all existing structures on the lot, the location and footprint of the proposed new construction or improvement, dimensioned setbacks from all property lines to existing and proposed structures, any recorded easements on the property, the location of driveways and access points, a north arrow, a scale bar or written scale, and the property address. For projects in flood zones, you may also need to show base flood elevation data. For ADUs, the site plan should indicate utility connections and any required fire department access.
Where do I submit my site plan and permit application in Antioch?: As of 2026, Antioch accepts permit applications both online and in person. The city's online permitting portal, accessible through the Antioch Community Development Department website at antiochca.gov, allows applicants to upload plans, submit forms, pay fees, and track review status without visiting City Hall. In-person submissions are accepted at the Building Division counter located at Antioch City Hall, 200 H Street, Antioch, CA 94509. Counter hours are generally Monday through Thursday; check the city's website for current hours since schedules can change. For large or complex projects, calling the Building Division in advance to confirm submittal requirements can save time.
What happens if I build without a permit in Antioch?: Building without a required permit in Antioch can have serious consequences. The city's Building Division has the authority to issue a stop-work order requiring all construction to halt immediately. You may be required to obtain a retroactive permit, which often involves additional plan check fees (sometimes double the standard fee), and an inspector may require portions of unpermitted work to be exposed or demolished so that structural and safety elements can be inspected. Unpermitted work can also create problems when you try to sell your home, as lenders and buyers may require the work to be legalized or removed. In some cases, the city can pursue code enforcement action, resulting in fines and liens on the property.
What are the ADU rules in Antioch, CA?: Antioch allows ADUs and Junior ADUs (JADUs) on single-family and multifamily residential lots in accordance with California state law. State law significantly limits the city's ability to impose restrictions, meaning ADUs can generally be built up to 850 square feet for a one-bedroom unit and 1,000 square feet for a two-bedroom unit (or up to 50 percent of the primary dwelling's size for attached ADUs). Setbacks are limited to 4 feet from rear and side property lines for detached ADUs. Owner-occupancy requirements for ADUs have been suspended through at least 2025 under state law. Antioch must act on a complete ADU permit application within 60 days. Impact fees may be waived for ADUs under 750 square feet. A site plan showing the ADU location, setbacks, and utility connections is required.

How to Create a Site Plan in Antioch

Confirm Your Project Needs a Permit: Before preparing any documents, verify with the Antioch Community Development Department whether your specific project requires a building permit and site plan. You can call the Building Division, use the city's online resources, or visit the counter at 200 H Street. Knowing the exact permit type required (building, grading, floodplain development, etc.) will determine what your site plan must include and which forms you need to complete.
Gather Your Property Information: Collect the documents you will need to prepare an accurate site plan. These include your property's assessor parcel number (APN), a copy of your deed or recorded plat map showing lot dimensions and easements, and any prior permit records for existing structures on the property. You can often find parcel maps through the Contra Costa County Assessor's Office online portal. Having accurate lot dimensions is essential for drawing a site plan to scale and correctly showing setbacks.
Prepare a Scaled Site Plan: Using your property information, create a site plan drawn to a standard engineering scale (such as 1 inch equals 20 feet). The site plan must show all existing structures, the proposed new construction, dimensioned setbacks from all property lines, easements, driveways, and a north arrow. Tools like Site Plan Creator allow you to produce a professional, permit-ready site plan online without specialized drafting software. Make sure all dimensions are labeled clearly and the scale is noted on the drawing.
Assemble Your Complete Application Package: In addition to your site plan, most Antioch permit applications require completed permit application forms, a project description, construction drawings or floor plans (for additions and ADUs), California Title 24 energy compliance documentation (where applicable), and payment of plan check fees. For projects in FEMA flood zones, include an elevation certificate or other floodplain documentation. Review the city's current submittal checklist on the Antioch Community Development Department website to ensure nothing is missing before you submit.
Submit and Track Your Application: Submit your complete application package through Antioch's online permitting portal or in person at City Hall. After submission, you will receive a permit number you can use to track the review status online. Plan review for standard residential projects typically takes three to six weeks. If the plan checker issues correction comments, respond promptly with revised plans or written responses. Addressing all corrections in a single resubmittal will speed up the approval process significantly.
Schedule Inspections and Close Out the Permit: Once your permit is approved and issued, you may begin construction. Antioch requires inspections at specific stages of the work, such as foundation, framing, rough mechanical or electrical, and final inspection. Schedule each required inspection through the city's inspection request system before covering any work. After passing all required inspections, the Building Division will issue a final approval or certificate of occupancy, officially closing out your permit and documenting the completed work in the city's records.