Residential permit rules in Tennessee
Representative cities: Nashville, Memphis. Covers 16 common home projects.
| Project | Permit? | Authority | Typical fee | Timeline | Go / No-Go | Key notes |
|---|---|---|---|---|---|---|
| 🏠 Accessory Dwelling Unit (ADU) | Permit required | city | Valuation-based; Nashville residential fee is $5.00 per $1,000 of valuation. | Nashville DADU review under Metro Code §17.16.250; varies by city. | Generally allowed | Nashville streamlined DADU rules in 2025 (removed alley-access requirement, raised size limits); owner-occupancy is required. Other cities follow state ADU allowances. Exempt: Nashville allows detached ADUs (DADUs) by right in most residential zones (Urban Services District). |
| 🪵 Deck / Porch | Conditional | city | Valuation-based; set by the issuing city/county. | Memphis OCCE ~5–10 business days for standard decks. | Generally allowed | Footing depth follows local frost line (shallow in Memphis, ~12 in Middle TN). Exempt: Decks ≤200 sq ft, ≤30 in above grade, not attached, not serving a required exit are exempt. |
| 🧱 Fence / Wall | Conditional | city | Often no building permit below local thresholds; historic-overlay lots differ. | Usually no building-permit review below threshold. | Generally allowed | Pool-enclosure fences must meet the 48 in barrier requirement. Exempt: Nashville: fences exempt except in Historic Overlay districts or over 7 ft; Memphis generally requires a permit for new fences. |
| 🛖 Shed / Outbuilding | Conditional | city | Valuation-based when over the size threshold. | Small sheds often exempt; larger sheds need plan review. | Generally allowed | Structures with plumbing, electrical, or gas, or used as living space, require a permit. Exempt: One-story detached sheds ≤200 sq ft are exempt under the TN Residential Code. |
| 🪜 Basement Finish | Permit required | city | Valuation-based; includes trade permits. | Standard plan review 2–4 weeks. | Generally allowed | Under the state program, unfinished-basement slabs do not require a slab inspection. Exempt: Cosmetic finishing (paint, flooring) is exempt. |
| 🚗 Garage / Carport | Conditional | city | Valuation-based when a permit is required. | New-structure plan review; varies by city. | Generally allowed | Converting a garage to habitable space requires a permit and code compliance. Exempt: State program exempts detached garages/sheds not used for living; local codes may differ. |
| ☀️ Rooftop Solar PV | Permit required | city | Building + electrical permits; fee set by city. | Varies; streamlined review common for standard residential PV. | Generally allowed | Net-metering and state incentives apply. Exempt: No size exemption for permanent rooftop PV. |
| 🌡️ HVAC Replacement | Permit required | city | Mechanical permit; fee set by city. | Trade permits often issued quickly. | Generally allowed | Equipment must meet the Tennessee Energy Code (2018 IECC + amendments). Exempt: No exemption for equipment replacement/installation. |
| 🍳 Kitchen Remodel | Conditional | city | Valuation-based when structural/plumbing/electrical work is included. | Standard review for permitted scopes. | Generally allowed | Full remodels pull separate plumbing/electrical/mechanical sub-permits. Exempt: Cabinet/countertop swap in the same layout is exempt. |
| 🛁 Bathroom Remodel | Conditional | city | Valuation-based when plumbing is relocated. | Standard review for permitted scopes. | Generally allowed | Ventilation to the exterior is required. Exempt: Fixture-for-fixture swap in place is often exempt. |
| 🏗️ Room Addition | Permit required | city | Valuation-based; includes trade permits. | Nashville standard residential review targets ~5 business days. | Generally allowed | The addition must meet code even though the existing home is not brought up to code. Exempt: State program: additions over 30 sq ft require a permit. |
| 🪟 Window / Door Replacement | Conditional | city | Usually no fee for in-kind swap; permit needed if opening is enlarged or under stricter local codes. | In-kind swaps typically need no review; Nashville requires a permit for window/door/exterior changes. | Generally allowed | Replacement products must meet energy-code U-factor when the code is triggered. Exempt: Same-size, in-kind replacement is generally exempt under the baseline code. |
| 🏘️ Roof Replacement | Conditional | city | Often over-the-counter or exempt for same-decking re-roof. | Nashville requires a permit for re-roofing; Memphis exempts re-roof where no decking is modified. | Generally allowed | Repairs not exceeding 33% of roof area are normal maintenance in Nashville. Exempt: Re-roof not changing decking/structure is often exempt (Memphis); Nashville requires a permit. |
| 🅿️ Driveway / Parking Pad | Conditional | city | Building permit often not required; curb-cut/right-of-way work is separate. | Right-of-way permits reviewed by the city/utility. | Generally allowed | A separate right-of-way permit is usually needed to cut the curb. Exempt: Sidewalks and driveways ≤30 in above grade are exempt (Memphis/OCCE exemption list). |
| 🏊 Swimming Pool / Spa | Permit required | city | Valuation-based; includes barrier/fencing and electrical bonding review. | Plan review varies; barrier inspection required. | Generally allowed | Tennessee requires a 48 in high barrier/fence around pools (Nashville and state standard). Exempt: Prefabricated pools <24 in deep and <5,000 gal may be exempt (Memphis/OCCE). |
| 🧱 Retaining Wall | Conditional | city | Valuation-based when over the height threshold. | Over-threshold walls need plan review. | Generally allowed | Walls in steep-slope or karst/expansive-soil areas may trigger soils review. Exempt: Walls ≤4 ft (Nashville) / ≤3 ft (Memphis) are exempt unless supporting a surcharge. |