Can I Build ADU in Knoxville, TN? (2026)
Find out if you can build a adu in Knoxville, TN. Rules, permit requirements, costs, and next steps.
Yes, ADUs are allowed in Knoxville, TN. California state law ensures by-right approval.
An Accessory Dwelling Unit (ADU) is a secondary housing unit on a residential lot — also called a granny flat, in-law suite, or backyard cottage. In Knoxville, TN, ADUs are permitted by right under state law, making them one of the most accessible ways to add housing on your property. ADUs can be detached, attached to the main home, or created by converting an existing garage or accessory structure.
ADU Rules in Knoxville
ADU Rules in Knoxville: Detached ADU max size: 750 sq ft. Attached ADU max size: 35% of primary dwelling floor area. Setbacks: 5 ft side, 5 ft rear. Owner-occupancy: Knoxville does not impose owner-occupancy requirements for ADU approval. Both the primary unit and ADU may be independently rented..
Costs & Fees
ADU permits in Knoxville: Total estimated permit cost: $1,200–$5,000 total fees. Contact the Knoxville Plans Review and Building Inspections for current fee schedule.
Timeline
Knoxville Plans Review and Building Inspections permit: typically 4-6 weeks for residential permits. Construction typically 4-12 months.
Next Steps
Next steps for building an ADU in Knoxville: 1. Review full ADU rules including size limits, setbacks, and parking. 2. Apply for an ADU permit through the Knoxville Plans Review and Building Inspections at https://www.knoxvilletn.gov/government/city_departments_offices/plans_review_and_building_inspections/permits. 3. Hire a licensed contractor familiar with TN ADU requirements.
Knoxville Plans Review and Building Inspections
Frequently Asked Questions
How does the University of Tennessee affect Knoxville's housing market?
The University of Tennessee's approximately 30,000+ students create intense rental demand in neighborhoods adjacent to campus — Fort Sanders, Laurel Avenue, and the Old North Knox corridor. This rental pressure has driven up property values in campus-adjacent areas. For ADU investors, these neighborhoods offer strong rental demand. Note that Fort Sanders is a historic district with design review for exterior changes. UT sports (Volunteers) also drive short-term rental demand on game weekends.
Can I build an ADU on my Knoxville property?
Yes. Knoxville allows accessory dwelling units in qualifying RN (Residential Neighborhood) zones. Maximum size is typically 750 sqft for detached ADUs. You'll need a building permit from Plans Review and Building Inspections. Tennessee has no statewide ADU law — Knoxville's local zoning ordinance governs. No owner-occupancy requirement. KUB connection fees apply for independent utilities.
What is the Metropolitan Planning Commission and does it cover Knox County too?
The Knoxville-Knox County Metropolitan Planning Commission (MPC) serves both the City of Knoxville and Knox County through a joint planning function. This is relatively unusual — Knoxville city and Knox County maintain separate governments but share planning services through the MPC. For property within Knoxville city limits, you work with Knoxville's Plans Review and Building Inspections for permits. For Knox County unincorporated areas, the county has separate permitting.
Does Knoxville have historic preservation requirements in Fort Sanders?
Yes. Fort Sanders is a National Register Historic District with Victorian architecture adjacent to the UT campus. Properties in Fort Sanders and other historic overlay (H-1) zones may require a Certificate of Appropriateness from the Knoxville Historic Zoning Commission for exterior modifications including additions, window replacements, roofing, and visible alterations. Contact Plans Review and Building Inspections to verify your property's historic status before beginning work.
What is KUB and how does it affect solar installation in Knoxville?
KUB (Knoxville Utilities Board) provides electricity, natural gas, water, and wastewater service to Knoxville and surrounding areas. KUB distributes power from TVA (Tennessee Valley Authority). For solar installations, you'll need KUB interconnection approval after receiving your electrical permit. KUB participates in TVA's net metering program. KUB also offers a Green Power Switch program for renewable energy support. Knoxville receives approximately 4.7 peak sun hours/day — viable for solar investment.
Source: Knoxville Plans Review and Building Inspections — Building Regulations. Last verified April 6, 2026. View source