Cost of accessory dwelling unit

Looking for cost of accessory dwelling unit in Knoxville, TN? Call AccessoryDwellingUnit Services for a contact a provider — no obligation. Licensed adu builders serve Knoxville and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.

About this service

Building an ADU involves several variables that shift the total investment. Your site conditions, the type of foundation, and the quality of finishes you choose will dictate whether you land on the lower or higher end of the spectrum. Because every lot is unique, we provide a breakdown of your specific project requirements to ensure full transparency. Exact pricing confirmed free on the call.

Frequently asked in Knoxville

What are the disadvantages of ADUs in Knoxville?

Potential disadvantages can include the upfront construction costs and the time it takes to build. You might also consider the impact on your current yard space and privacy. However, these can often be mitigated with careful planning and design by experienced local pros.

How much does an ADU cost in Tennessee?

What are the rules for ADUs in Tennessee?

Can I build an ADU on any property in Knoxville?

Not all properties may be suitable for an ADU due to zoning restrictions, lot size, or existing structures. The pros you'll speak with can assess your specific property in areas like West Hills or North Knoxville to determine feasibility. They'll explain any limitations based on local codes.

What permits are needed for an ADU in Knoxville?

What kind of ADUs can be built in Knoxville?

You can often build various types, including detached units, attached units (like basement or garage conversions), and accessory structures. The best option for your Knoxville property depends on your goals and available space. The pros can discuss design possibilities.

Also serving nearby: Asheville · Chattanooga · Murfreesboro · Roswell · Sandy Springs

All cities in Tennessee →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

198,162residents

2,007per sq mile

8ZIP codes served

Serving all of Knoxville — population 198,162; about 2,007 residents per square mile across 98.7 sq mi. ZIP codes covered include 37901, 37902, 37909, 37912, 37914, 37915, 37916, 37917.

Neighborhoods served in Knoxville: Old City, Bearden, West Hills, Downtown Knoxville, Fort Sanders, North Knoxville — and every surrounding area.