ADU / Guest House Permit Requirements in Maynardville, TN

Union County is EXEMPT on the TN State Fire Marshal's residential jurisdictions list, meaning it enforces building codes locally. Building permits must be purchased in person at the Assessor of Property office — no online portal. Fee schedule not published online; call (865) 992-3211 for current fees. Tennessee state electrical permits required separately (inspector: Eric Ramsey, (423) 626-0724). Contractor licensing: TN statewide $25,000+ threshold; no HIC requirement in Union County.

Population: 2,568 Code: 2018 Verified: 2026-04-07 3 local rules

When you DO need a permit

TN (Union County), building a detached ADU (accessory dwelling unit or guest house) requires a building permit as new residential construction under Tennessee state law. Electrical, plumbing, and mechanical permits are also required. Contact the Union County Assessor of Property at (865) 992-3211.

Source: Tennessee State Building Codes / TCA 68-120-101 — new construction

TN (Union County), converting space into an attached ADU or adding an attached dwelling unit requires building, electrical, plumbing, and mechanical permits. This is treated as an addition under Tennessee state law. Permits must be purchased in person at the Union County Assessor of Property office.

Source: Tennessee State Building Codes / TCA 68-120-101 — additions over 30 sq ft

TN (Union County), converting an existing structure (garage, basement) into a dwelling unit requires building, electrical, and plumbing permits. Creating habitable space triggers building permit requirements. Contact the Assessor of Property at (865) 992-3211.

Source: Tennessee State Building Codes / 2018 IRC — Union County local enforcement

ADU / Guest House Permit Costs: Maynardville vs. Nearby

CityEstimated Fee
Maynardville
Nashville $1,000 – $5,000
Nashville $500 – $3,000
Nashville $800 – $4,000

Fees shown are estimates based on local building code data. Actual fees may vary based on project scope and valuation.

Zoning Considerations

Zoning

ADU regulations vary dramatically by state and city. Many states (CA, OR, WA) have preemption laws that override local zoning restrictions. Check both state law and local zoning before designing.

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Building Department Contact

NameUnion County Assessor of Property
Address901 Main Street, Suite 106, Maynardville, TN 37807
HoursMon-Fri 8am-4pm

Frequently Asked Questions

Contact Maynardville's building department for current ADU / Guest House permit fee information. Fees typically vary based on project scope and valuation.

It depends on the specifics of your project. Some smaller ADU / Guest House projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.

Working without a required permit in Maynardville can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.

Contact Maynardville's building department for current processing times. Timelines vary based on project complexity and whether plan review is required.

Learn More About ADU / Guest House Permits

Read our complete guide covering permit requirements, costs, common exemptions, and the application process.

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Disclaimer: This information was last verified on 2026-04-07. Building permit requirements may change. Zoning requirements (setbacks, lot coverage, height limits) are separate and vary by location. Always confirm with your local building and planning departments before starting your project. PermitMint provides general guidance, not legal advice.