Knox County, TN Accessory Structures: Garage Conversions (2026)
Garage conversion rules in Knox County, TN, sometimes called garage-to-ADU or accessory living unit conversions, govern permits, ceiling height, egress, and parking replacement.
Key Facts
- Dwellings per lot
- One only
- Permit
- Required for structural/electrical
- Home occupation in garage
- Not allowed
- Home office floor area
- Up to 25%
- Enforcing office
- Code Administration
Summary
Converting a garage into living space in unincorporated Knox County must keep the lot to one dwelling and cannot create a separate second unit. A home occupation may run inside the main dwelling, but not in any accessory building. A residential building permit is required for structural or electrical work.
No home occupation shall be conducted in any accessory building.
Full Breakdown
The Knox County Zoning Ordinance permits only one house per lot, so a garage conversion cannot become an independent second dwelling. If the garage is part of the main house, converting it to living space is regulated as an alteration of the principal dwelling and needs a county residential building permit for structural, electrical, plumbing, or mechanical changes. A home occupation is allowed inside a dwelling on up to 25% of floor area, but the ordinance flatly bars conducting a home occupation in any accessory building such as a detached garage. Check your zone and lot coverage (30% cap) with Knoxville-Knox County Planning before converting.
Violations & Fines
Unpermitted conversions and prohibited accessory-building uses are enforced by the county Department of Code Administration; reversal or permitting may be required.
Frequently Asked Questions
Can I turn my detached garage into an apartment?
Can I run a business from a converted garage?
Sources & Official References
Other rules in Knox County
Compare Knox County to another location·View the Tennessee accessory structures overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.