County Building Permits

Trinity County Building Permit Guide (Unincorporated Area)

How to apply for a building permit in unincorporated Trinity County, California. Permit authority, application steps, fees, and inspection requirements.

California Updated March 2026

Permit Authority

All properties within unincorporated Trinity County. Trinity County has no incorporated cities in this permit set, and county code states projects in unincorporated territory are permit-restricted unless exempt.

Department
Trinity County Building Division, Community Development Department
Address
61 Airport Road, PO Box 476, Weaverville, CA 96093
Phone
530-623-1354 (building division office); 530-623-4890 (inspections)

Online Permit Portal

Platform: PDF + county contact flow (in-person/phone/mail submission) • Account required: No • Submission: In-person only

Application Process

  1. Download the building permit application and planning review checklist.
  2. Prepare the required package, including project description, APN, site plans with square footage and setbacks, building plan dimensions and heights, and any project-specific supporting sheets.
  3. Submit 3 sets of plans and required site maps to the Building Division following county instructions.
  4. Include the required plan review fee deposit with the plans; building plans are returned only after minimum requirements are met.
  5. Wait for permit review, which the county states can take up to 6 weeks after a complete submittal.
  6. Do not start construction until the permit is issued.

Typical processing time: Up to 6 weeks after complete submittal.

Source: Trinity County Building Division, Community Development Department

General Requirements

Construction in unincorporated Trinity County is generally permit-based unless an ordinance exemption applies.

Required Documents

  • Completed building permit application
  • 3 complete sets of plans
  • Plot or site plans with setback and parcel data
  • Project description
  • APN
  • Utility, sewer, water, or development approvals where applicable
  • Required third-party approvals such as Environmental Health or road permits
Permit validity
Permits are deemed revoked if work has not started or is paused for 180 days without extension or communication.
Building code
Applicable California Building Code year as required by the county permit packet, plus CalFire fire-safe and local fire-safe requirements.
Owner-builder
The county uses an owner-builder packet. The owner remains the legal point of responsibility unless the permit is filed by a licensed contractor, and owner-builder permits can trigger additional legal and employment obligations.
Contractor requirements
Contractors are required to be California licensed and bonded. Permit forms and the owner-builder declaration reference CSLB requirements.

Fees

Plan check fee
A plan review fee deposit is required with building plans.
Permit fee formula
Fee schedule indicates valuation-based and work-type-based charges using the county building fee ordinance and 2023 ICC valuation sheet.
Payment note
The county states it accepts personal checks, cashier's checks, money orders, credit cards, and exact cash, and does not make cash change.

Fees change. Verify current amounts at the official fee schedule.

Work That Does NOT Require a Permit

  • Detached accessory structures 120 square feet or less used for storage only
  • Fences 7 feet high or less, subject to zoning and standards
  • Retaining walls 4 feet high or less
  • Water tanks supported directly on grade with a capacity of 5,000 gallons or less and a height-to-diameter ratio of 2:1 or less
  • Painting, papering, tiling, carpeting, cabinets, countertops, and similar finish work
  • Prefabricated swimming pools less than 24 inches deep
  • Swings and playground structures
  • Window awnings within projection limits that do not require additional support
  • Decks 200 square feet or less and not more than 30 inches above grade
  • Conditional agricultural building exemptions subject to letter-of-intent review and clearance

Important: Exempt work can still require zoning or related approvals. Plumbing and electrical work for agricultural exempt structures still requires applicable permits, and any ambiguous project should be confirmed with the Building Division before work begins.

Inspections

How to Schedule

  • 530-623-4890 (phone)
Scheduling deadline
Same-day inspections generally require requests before 8:00 AM.
Inspection hours
Daily, 8:00 AM to 3:00 PM

Typical inspection sequence: Typical sequence: foundation, underfloor plumbing, roof sheathing nailing, 4-way inspection for framing and rough trades, insulation, lath or wallboard, and final inspection leading to certificate of occupancy.

Additional Resources

Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the Trinity County Building Division, Community Development Department before applying.

Need help with your project?

Navigating permits in Unincorporated Trinity County can be complicated.

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Important: This page is an educational resource provided by jaspector.com. It is not legal advice, and it does not substitute for official guidance from the permit authority listed above. Permit requirements, fees, and processes change frequently. Always verify current requirements directly with the issuing department before beginning any construction project. Use of this page does not create an attorney-client relationship. Jaspector assumes no liability for any outcomes arising from reliance on this information.
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