The Wilson County Building Codes Division, at 233 East Gay Street in Lebanon, enforces the 2021 IRC with the 2018 energy code for unincorporated Wilson County and also issues building permits inside the City of Watertown. It collects the Adequate Facilities Tax centrally — for the county and for Lebanon, Mt. Juliet and Watertown — and takes permit applications only from the owner of record or a state-licensed contractor.
Two rules shape a Wilson County application. First, the Adequate Facilities Tax is collected in the county office for the cities as well as the county, so a Mt. Juliet or Lebanon permit still runs through a county AFT receipt. Second, only the property owner or a Tennessee-licensed contractor may apply. Electrical is generally a state permit, and an accessory structure under 120 square feet needs no building permit.
Scope: unincorporated Wilson County and the City of Watertown through the Building Codes Division. Lebanon and Mt. Juliet permit their own work — but the county collects their AFT.
The county collects the Adequate Facilities Tax for its cities. Wilson County's Building Codes office collects the AFT for the county and for Lebanon, Mt. Juliet and Watertown, and a city permit packet lists the county AFT receipt among the documents required before the city permit issues. And only the owner of record or a state-licensed contractor may apply for a building permit here, so settle both points before you file.
What requires a permit in Wilson County?
The Wilson County Building Codes Division, at 233 East Gay Street in Lebanon, enforces the county’s adopted International Codes for unincorporated Wilson County — one of the fastest-growing parts of the Nashville metro, anchored by Mt. Juliet and Lebanon — and issues building permits inside the City of Watertown too, with the permit fee paid to the city. Lebanon and Mt. Juliet run their own permitting inside their limits, so a parcel there goes to the city rather than the county.
As in neighbouring Sumner County, the Adequate Facilities Tax (AFT) is central here — and Wilson County goes a step further by collecting it centrally. The AFT for Wilson County and for the cities of Lebanon, Mt. Juliet and Watertown is all collected in the county Building Codes office. A Mt. Juliet residential permit packet, for example, lists a Wilson County adequate facilities tax receipt among the documents required before the city permit issues. Tennessee does not have one permitting model, it has three, and which one applies decides who your building official actually is. A jurisdiction that has adopted codes meeting the state minimum and enforces them is an exempt jurisdiction: it runs its own plan review, permits and inspections, and the state stays out except for state buildings, schools and a handful of licensed occupancies. A jurisdiction that has not is non-exempt, and the State Fire Marshal's Office is the building official there, working through contracted deputy building inspectors who cover several counties each. And a jurisdiction that has passed a two-thirds resolution under T.C.A. § 68-120-101(b)(1)(B) is an opt-out or non-code jurisdiction, where one- and two-family dwellings sit outside the statewide standards altogether.
The county enforces the 2021 International Residential Code with its adopted appendices and the 2018 International Energy Conservation Code with state-approved amendments. A permit is required for the full range of residential structures, and one Wilson-specific rule is worth stating up front: only the property owner of record or a state-licensed contractor may apply for a building permit in Wilson County. An accessory structure under 120 square feet does not need a building permit.
Two residential details are worth knowing before you design. Automatic fire sprinklers under IRC Section R313 are not mandatory in Tennessee — T.C.A. § 68-120-101(a)(8) prohibits the State Fire Marshal from requiring them in one- and two-family dwellings, though a municipality may impose its own requirement. And the residential code reaches additions of 30 square feet or more of interior space, which is a smaller trigger than most people assume.
Permit required
- New residential and commercial construction, and additions
- Structural alterations, repairs, and changes of occupancy
- Accessory structures at or above 120 square feet
- Swimming pools and their required barriers
- Decks, and exterior structural work
- Plumbing, mechanical, and gas work
- Electrical work — generally a state permit
- New development subject to the Adequate Facilities Tax
Typically exempt
- Accessory structures under 120 square feet
- Painting, flooring, and cosmetic finishes
- Routine maintenance not altering structure or a regulated system
- Work inside Lebanon or Mt. Juliet
Short on time to read all of this?
Get a free quote →Wilson County building department: who handles permitting
The Building Codes Division administers plan review, permitting and inspections for the unincorporated county, and staff can pull maps, plats and other documents to help work out what a project needs. Commercial projects require plan review, and the county's own framing is that it is there to help with permitting needs — which in practice rewards arriving with the owner or licensed-contractor question already settled, because those are the only two parties it will take an application from.
The centralised Adequate Facilities Tax is the structural feature to understand. Because the county collects the AFT for itself and for Lebanon, Mt. Juliet and Watertown, the county Building Codes office is a common step for city and county projects alike. A Mt. Juliet builder brings the Wilson County AFT receipt to the city; a Lebanon or Watertown builder does the same. Confirm the current AFT rate with the county before pricing new square footage anywhere in Wilson County.
On a septic property the TDEC approval comes before the county can issue, and the system is sized to bedroom count. As with the rest of the state, the electrical permit is generally a separate state record rather than a county one, so a Wilson County project typically runs a county building permit and a state electrical permit on two tracks.
| Detail | Information |
|---|---|
| Authority | Wilson County Building Codes Division |
| Covers | Unincorporated Wilson County and the City of Watertown |
| Cities running their own | Lebanon, Mt. Juliet |
| Office | 233 East Gay Street, Lebanon, TN 37087 · Monday to Friday 8:00am to 4:00pm, no permits processed after 3:30pm · applications through the MGO Connect portal |
| Phone | (615) 444-3025 |
| Codes enforced | 2021 IRC with appendices; 2018 IECC with state amendments |
| Adequate Facilities Tax | Collected here for the county and for Lebanon, Mt. Juliet and Watertown |
| Who may apply | Owner of record or a state-licensed contractor only |
| Electrical | Generally a state permit via CORE |
The county collects the AFT for the cities too. Wilson County's Building Codes office collects the Adequate Facilities Tax for the county and for Lebanon, Mt. Juliet and Watertown, so a city permit still runs through a county AFT step. And only the owner of record or a state-licensed contractor may apply for a building permit here — settle that before you file.
Confirm from the parcel whether the site is in unincorporated Wilson County or Watertown (both permitted by the county) or inside Lebanon or Mt. Juliet, because the permitting office changes at those city lines — though the county collects the Adequate Facilities Tax for those cities, so the county Building Codes office is a step either way.
In 2025, building permits issued in unincorporated Wilson County authorized 382 new privately owned housing units, all of them single-family homes, according to the U.S. Census Bureau Building Permits Survey.
Wilson County permits: record types and what each covers
Wilson County runs residential and commercial building records, with the Adequate Facilities Tax attaching to new development. These are the records you are likely to file:
Not sure this scope needs a permit?
Get a free quote →Residential permit types
| Permit type | What triggers it | Review path | Fee basis |
|---|---|---|---|
| New construction | New dwellings, additions, and accessory structures above the local size threshold | Plan review against the adopted residential code, plus zoning; the state floor is the 2018 IRC with Appendix Q | Valuation-based |
| Addition | Added interior space, including additions of 30 square feet or more | Structural and energy review; the 30 square foot interior trigger is smaller than most applicants expect | Valuation-based |
| Renovation / alteration | Structural changes, layout changes, or added plumbing, mechanical, or electrical | Plan review scaled to scope; renovations of existing one- and two-family dwellings sit outside the state minimum standards | Valuation-based |
| Reroof | Roof covering replacement, recover, and structural deck repair | Deck and dry-in inspection; plan review rarely required | Valuation or squares |
| Solar photovoltaic | Rooftop or ground-mount arrays, with or without battery storage | Structural review of the attachment locally, with the electrical scope usually permitted and inspected by the state | Flat or system-size based |
| Battery energy storage | Wall or floor-mounted storage added to a dwelling | Electrical review plus fire separation and location check | Flat or per-permit minimum |
| Electrical | Service changes, panel upgrades, new circuits, EV chargers, and rewiring | In most of Tennessee a state record bought through CORE and inspected by a contracted Deputy Electrical Inspector, not a local one | Per-permit or per-device |
| Plumbing | New piping, repipes, fixtures, gas piping, and water heater replacement | Trade review; performed by a licensed plumber or a Limited Licensed Plumber below the contractor threshold | Per-permit minimum or per-fixture |
| Mechanical / HVAC | Changeouts, new ductwork, and refrigeration | Trade review; the contractor licence attaches once the trade portion reaches the statutory threshold | Per-permit minimum or per-unit |
| Deck and porch | New decks, screened porches, and structural rebuilds | Structural review of footings, ledger attachment, and guards | Valuation or flat |
| Swimming pool | In-ground and above-ground pools | Barrier, bonding, and electrical review; the bonding scope generally follows the state electrical record | Valuation or flat |
| Manufactured home set-up | Placing or re-siting a manufactured home | Zoning, floodplain, and anchoring review; manufactured homes sit outside the state residential code but are installed under state installation rules, and local zoning still applies | Flat or per-unit |
| Demolition | Full or partial demolition of a dwelling or accessory structure | Utility disconnect confirmation and site restoration check | Flat |
| New single-family dwelling | Building a new home in the unincorporated county | Building review against the 2021 IRC, with the AFT and applicant check | Per-project AFT plus permit fee |
| Accessory structure at or above 120 sq ft | A shed, garage or barn over the exemption | Building review; under 120 square feet needs no permit | Permit fee by scope |
Rather talk it over?
Call 1-855-478-4290 →Commercial permit types
| Permit type | What triggers it | Review path | Fee basis |
|---|---|---|---|
| New commercial construction | Ground-up commercial, industrial, and institutional buildings | Concurrent review against the adopted building code, fire, and zoning; the state floor is the 2021 IBC with Tennessee amendments | Valuation-based |
| Tenant improvement / upfit | Interior fit-out of an existing tenant space | Building, trade, and life-safety review; accessibility attaches on change of use | Valuation-based |
| Change of occupancy | Converting a building or space to a different use group | Occupancy classification, egress, and accessibility review | Valuation or flat |
| Commercial electrical | Service, distribution, and branch circuit work | State record in most jurisdictions unless the city or county is on the State Fire Marshal’s exempt list and inspects its own electrical | Per-permit or valuation |
| Commercial plumbing | Process piping, fixtures, backflow, and grease waste | Trade review; backflow and grease interceptor sign-off where applicable | Per-fixture or valuation |
| Commercial mechanical | Rooftop units, kitchen exhaust and hood systems, and refrigeration | Trade review; hood and suppression systems draw fire review alongside mechanical | Per-unit or valuation |
| Commercial reroof | Roof covering replacement on a commercial structure | Deck, dry-in, and attachment inspection | Valuation or squares |
| Signage | Wall, ground, and illuminated signs | Zoning review for size and placement, plus electrical where illuminated | Flat or per-sign |
| Land disturbance | Clearing, grading, and stormwater-triggering site work | Erosion and sediment control review, separate from the building permit | Acreage-based |
| Commercial demolition | Full or partial demolition of a commercial structure | Utility disconnect, asbestos notification, and site restoration | Flat or valuation |
| State Fire Marshal plans review | Occupancies requiring State Fire Marshal approval, including schools and certain licensed facilities | Filed with the state through the plans submittal portal, in addition to and not instead of the local record | State fee schedule |
| Commercial new construction | A new commercial building in the county | Full plan review, with the AFT on the project | Per-project AFT plus permit fee |
| Commercial tenant finish | Fitting out a commercial space | Plan review of the tenant scope against the adopted codes | Permit fee by scope |
Residential
- Single-discipline review in most cases
- The electrical record is usually a separate state permit, not a line on the building permit
- Contractor licence attaches at the statutory threshold; a Home Improvement licence may apply below it in nine counties only
- Septic properties need a TDEC septic construction permit before the system is installed, and some counties add their own
Commercial — multi-discipline
- Concurrent review across building, trades, fire, and zoning
- Signed and sealed plans across every affected discipline
- The licensee's monetary limit caps the job value, separately from the permit
- Accessibility and life-safety review attach to any change of occupancy
Records you will actually see in Wilson County
| Record | What it covers |
|---|---|
| Residential building permit | New homes, additions, alterations, and repairs |
| Commercial building permit | Commercial construction and tenant work |
| Accessory structure | At or above 120 square feet |
| Swimming pool | With barrier and bonding review |
| Plumbing permit | New piping, repipes, fixtures, and gas piping |
| Mechanical / gas permit | HVAC changeouts, ductwork, and gas work |
| State electrical permit | Through core.tn.gov, not the county |
| Demolition permit | Full or partial demolition |
Rather not deal with the Wilson County building department?
Get a free quote →Solar permits in Wilson County
A residential solar installation in unincorporated Wilson County is a county building permit for the structural attachment plus a state electrical permit for the wiring and interconnection, since electrical here is generally a state record through CORE. Only the owner of record or a state-licensed contractor may pull the county building permit, so a solar contractor handling the paperwork must hold the state licence. The local power company sets the meter release and usually waits on an approved electrical inspection, so confirm the interconnection path early.
Roofing permits in Wilson County
A re-roof in unincorporated Wilson County is a county building permit reviewed against the 2021 IRC. A like-for-like replacement is straightforward; adding load or altering the roof structure draws closer review, and a remodel that changes load-bearing elements is treated as permit-triggering rather than routine. The owner of record or a licensed contractor pulls the permit, so confirm who is applying before the roofer starts.
Tennessee solar jobs usually need a state electrical permit, unless the city or county runs its own electrical inspections, plus any local building review; roofing follows the adopted code and the manufacturer's instructions. Tennessee rules
Wilson County permit cost
As in Sumner County, two charges drive the cost of building in Wilson County: the building permit fee set by the Building Codes Division, and the Adequate Facilities Tax collected centrally for the county and its cities. On a new dwelling the AFT is $5,000, paid by a separate check from the permit fee, so it is the charge most likely to be underestimated.
Electrical is generally a separate state permit through CORE, so that cost is a state fee rather than a county line item. Confirm the current building permit fee and AFT rate with the county before budgeting, and remember the AFT is collected here even for a Lebanon, Mt. Juliet or Watertown project.
| Fee component | How it works |
|---|---|
| Building permit | Set by the Building Codes Division against the submitted scope |
| Adequate Facilities Tax | Collected here for the county and for Lebanon, Mt. Juliet and Watertown |
| Commercial | Plan review required |
| Electrical | State permit fee via CORE, not a county line item |
| Septic properties | TDEC septic permit required before the system is installed |
| Accessory under 120 sq ft | No building permit required |
| Confirm | Current fee and AFT rate with the Building Codes Division |
Want a precise number for a specific Wilson County project? Send us the scope and we will price the permit path before you file.
Wilson County trade permits
Electrical is generally a state permit; plumbing, mechanical and gas follow the normal contractor rules. Four Wilson specifics decide whether your application moves:
Only the owner or a licensed contractor may apply
Wilson County will take a building permit application only from the property owner of record or a Tennessee state-licensed contractor. An unlicensed party who is not the owner cannot pull the permit, so settle who is applying before you start.
The AFT is collected here for the cities too
The county Building Codes office collects the Adequate Facilities Tax for the county and for Lebanon, Mt. Juliet and Watertown. A city permit still runs through a county AFT step, so price it into any new build in Wilson County.
Electrical is generally the state's
Wilson County is not on the State Fire Marshal’s list of jurisdictions that run their own electrical inspections (Mt. Juliet is, inside its limits; Lebanon and Watertown are not), so the electrical record is usually a state permit through CORE. Confirm rather than assuming it comes with the building permit.
Small accessory structures are exempt
An accessory structure under 120 square feet does not need a building permit in Wilson County. Above that, and for anything with a regulated system, a permit applies — confirm before relying on the exemption.
Want this handled start to finish?
Get a free quote →Tennessee licenses contractors through the Board for Licensing Contractors for jobs of $25,000 or more; a Home Improvement licence applies below that only in the nine counties that opted in. Tennessee rules
Wilson County permit application: how to apply step by step
Here is how to get a building permit in Wilson County, from confirming the requirement through to close-out. Each step below corresponds to a real decision point where projects commonly stall.
Lebanon and Mt. Juliet permit their own work; the county permits the unincorporated area and Watertown. Settle jurisdiction from the parcel before you start — but note the county collects the Adequate Facilities Tax for those cities either way.
Only the property owner of record or a Tennessee state-licensed contractor may apply for a building permit in Wilson County. Confirm which one is pulling the permit before you file.
On a septic property, obtain the TDEC approval before the county can issue. Design to the 2021 IRC with appendices and the 2018 energy code with state amendments.
Confirm the current AFT rate with the county and include it in the project cost. The county collects it for city projects too, so it applies wherever in Wilson County you build.
Apply through the MGO Connect portal, clear plan review (required for commercial), and pay the building permit fee and the AFT on separate checks (the office takes only checks, cashier’s checks and money orders, and processes nothing after 3:30pm). Electrical is a separate state permit through CORE.
Book county building inspections, run the state electrical inspection on its own track, and carry the project through to the certificate of occupancy before legal use.
Inspections in Wilson County
County building inspections are scheduled against the issued permit, with typical checkpoints running footing and foundation, trade rough-ins, framing, insulation and final, reviewed against the 2021 IRC. The permit and approved plans should be on site, and remodels with major load changes, major use changes or major dwelling-type changes are treated as permit-triggering work rather than routine maintenance.
Electrical inspections run on the state's track through CORE, arranged and regulated by the state rather than the county. Keep the county building track and the state electrical track separate so a hold on one is not mistaken for a hold on the other.
Because the Adequate Facilities Tax is settled at issuance, by inspection time it is behind the project — but on an addition or change of occupancy, confirm what was previously permitted against what is standing, because unpermitted square footage surfaces there and can carry its own AFT question.
Keep the permit and approved plans on site. Remodels that alter load-bearing elements, change a space's use, or change the dwelling type are permit-triggering rather than routine — confirm scope with the division before you treat work as exempt.
Wilson County permit search and official resources
Wilson County publishes its Building Codes Division information and adopted codes online, with the state licensing and electrical resources that sit alongside them.
Inspections are where schedules slip.
Get a free quote →- Wilson County Building Codes Division
- Wilson County Adequate Facilities Tax (Building Codes Division)
- TN Board for Licensing Contractors
- State electrical permits (CORE)
- State Fire Marshal codes enforcement
- TDEC subsurface sewage disposal
Frequently asked questions
Who issues building permits in Wilson County, TN?
The Wilson County Building Codes Division, at 233 East Gay Street in Lebanon, for unincorporated Wilson County and the City of Watertown. Lebanon and Mt. Juliet run their own permitting. The department line is (615) 444-3025; the office is open 8:00am to 4:00pm and processes no permits after 3:30pm.
What is the Adequate Facilities Tax in Wilson County?
A privilege tax on new development that helps pay for the public facilities growth requires — $5,000 on each new dwelling, including a new mobile home. Wilson County collects it centrally — for the county and for the cities of Lebanon, Mt. Juliet and Watertown — in the county Building Codes office, so a city permit still runs through a county AFT step.
Who can apply for a building permit in Wilson County?
Only the property owner of record or a Tennessee state-licensed contractor. An unlicensed party who is not the owner cannot pull the permit, so settle who is applying before you file.
Which building code does Wilson County enforce?
The 2021 International Residential Code with its adopted appendices and the 2018 International Energy Conservation Code with state-approved amendments. As a local building authority under the statewide minimum standards, the county's adopted set governs.
Does Wilson County issue electrical permits?
Generally no. Wilson County is not on the State Fire Marshal’s list of jurisdictions that run their own electrical inspections (Mt. Juliet is, inside its limits; Lebanon and Watertown are not), so the electrical record is usually a state permit through CORE, inspected by a state-contracted Deputy Electrical Inspector.
Do I need a permit for a shed in Wilson County?
An accessory structure under 120 square feet does not need a building permit in Wilson County. At or above 120 square feet, or for a structure with a regulated system such as electrical or plumbing, a permit applies — confirm before relying on the exemption.
Do I need a contractor licence in Wilson County?
A Tennessee contractor licence is required to bid or perform work valued at $25,000 or more, including labour and materials. The same threshold reaches electrical, mechanical, plumbing, HVAC and roofing subcontractors on their own portion; masonry subcontractors are licensed at $100,000. Only the owner or a licensed contractor may apply for the permit.
Do I need a Home Improvement licence in Wilson County?
No. Wilson is not one of the nine Tennessee counties that require the Home Improvement licence. Below the $25,000 contractor threshold there is no separate state home improvement credential here, though local registration and trade licences still apply.
Do I need a septic approval before a building permit in Wilson County?
On a parcel without public sewer, yes. The state's TDEC subsurface sewage disposal program issues the septic permit, and it must be in hand before the county can issue the building permit. The system is sized to bedroom count.
Does the county collect the AFT for Lebanon and Mt. Juliet?
Yes. The Wilson County Building Codes office collects the Adequate Facilities Tax for the county and for Lebanon, Mt. Juliet and Watertown. A city permit packet lists the county AFT receipt among the documents required before the city permit issues.
Does Wilson County check my HOA covenants?
No. Deed restrictions, covenants and subdivision regulations are private matters between the owner and the subdivision. A permit that clears the county can still breach a covenant, and the county will not have checked.
What remodels need a permit in Wilson County?
Remodels with major load changes such as altering or adding load-bearing walls or beams, major use changes such as converting attic space to living space, and major dwelling-type changes are permit-triggering. Confirm scope with the division rather than assuming a remodel is exempt.
Simplify Wilson County permitting with Alliance Permitting
Wilson County's centrally-collected Adequate Facilities Tax, its owner-or-licensed-contractor application rule and its state electrical route reward applicants who price the AFT into the job, settle who is applying, and keep the county and state tracks straight.
Trusted by leading builders, developers, and national contractors — 21+ years of filing in the jurisdictions we write about.
Contractors and builders choose Alliance for Wilson County because the work is done by people who have stood at the counter:
- Right authority — the county (unincorporated area and Watertown) or Lebanon or Mt. Juliet, resolved from the parcel.
- AFT priced in — the Adequate Facilities Tax confirmed with the county before the bid, including on city permits.
- Right applicant — the owner of record or a state-licensed contractor pulling the permit, settled before filing.
- Complete oversight — every Wilson building record, state permit and inspection tracked across your jobs in one place.
Alliance Permitting is a permit documentation and expediting service in Tennessee. We are not a law firm and do not provide legal advice, and we are not the permitting authority.
Ready to break ground in Wilson County sooner?
Let Alliance prepare, file, and track your Wilson County permits while your crew stays on the job.
More Tennessee permitting guides
This guide is provided by Alliance Permitting for general information about Wilson County permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.