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When a permit is required
Permit triggers and exempt work for Williamson County
County page states building and other necessary permits may be completed through the county system; project types listed in the county IDT system include residential building permits, nonresidential building permits, signs, retaining walls, floodplain development, driveway permits, change of use or tenant requests, and related development submissions
- Exempt Residential roof repair or replacement does not require a permit or inspection when it is ordinary repair and does not involve structural work under adopted IRC Section R105.2.2
- Exempt Standard permit exemptions in the county's adopted 2021 IRC and 2021 IBC
Note: Exemption from permit does not authorize work that violates adopted codes or other ordinances.
- Uploaded project documents per the county checklist
- Plans and supporting materials vary by project type
- Building code
- County adopted 2021 IBC, 2021 IRC excluding dwelling sprinkler section and electrical chapters, 2021 IPC, 2021 IMC, and 2018 IECC with 2009 tables effective September 30, 2024; state and SFMO approvals still apply for educational, daycare, and large assembly occupancies
- Permit validity
- Not clearly posted on the county permit and inspection pages reviewed
- Owner-builder
- Not clearly posted on the pages reviewed
- Contractor requirements
- Not clearly summarized on the permit overview page reviewed; applicants should confirm Tennessee contractor licensing requirements with the county and the Tennessee Board for Licensing Contractors
Application process
Typical processing: The county does not post a general plan review number on the pages reviewed, but the portal sends status notices at each review stage.
- 01 Register or sign in to the Williamson County electronic plan review system.
- 02 Select the project type and complete the online intake fields.
- 03 Upload all required project documents from the county checklist.
- 04 Submit the project and monitor email notices from info@idtplans.com for acceptance, denial, and review status.
- 05 Pay fees online or at the Williamson County Administrative Complex, Suite 400.
- 06 After permit issuance, schedule inspections as construction reaches each required phase.
Typical processing time: The county does not post a general plan review number on the pages reviewed, but the portal sends status notices at each review stage.
Fee schedule
Williamson County building permit fees
Checks payable to Williamson County Government; separate checks required for building permits and privilege taxes; county also allows online fee payment in the portal
Fees change periodically. Confirm at the official fee schedule ↗ before budgeting.
Required inspections
Scheduling and sequence
- County electronic plan review system (online)
- Scheduling deadline
- No same-day cutoff or public inspection window posted on the page reviewed
Typical sequence: Footings, foundation, slab, slab plumbing if applicable, framing, mechanical, plumbing, insulation, final building for certificate of occupancy, and storm water
Frequently asked
Common questions about unincorporated Williamson County permits
01 Do I need a building permit in unincorporated Williamson County, TN? ▸
02 How much does a building permit cost in unincorporated Williamson County, TN? ▸
03 How do I apply for a building permit in unincorporated Williamson County, TN? ▸
04 How long does it take to get a building permit in unincorporated Williamson County, TN? ▸
05 What work is exempt from building permits in unincorporated Williamson County, TN? ▸
06 How do I schedule a building inspection in unincorporated Williamson County, TN? ▸
Educational reference. Permit rules and fees change — confirm current requirements directly with Williamson County Building Codes before applying. Jaspector is not legal advice.