FAQ DADUs – Detached Accessory Dwelling Units

//FAQ DADUs – Detached Accessory Dwelling Units

FAQ DADUs – Detached Accessory Dwelling Units

If you’re a longtime resident of Nashville, you’ve no doubt noticed an increase in the number of Detached Accessory Dwelling Units (DADUs), especially in some of our historic neighborhoods. DADUs—along with Attached Accessory Dwelling Units (AADUs), Owner Accessory Units (OAUs), and secondary apartment units—have “bec[o]me popular ways to add density … and provide extra income for homeowners” in Davidson County.

A typical DADU in Nashville is a two-story, multi-functional building with a garage on the lower level and a second floor with livable space—usually a studio or one bedroom apartment, or sometimes a home office. Done right, a DADU is both functional and aesthetically pleasing, and can provide lifestyle and/or financial benefits.

With all the above in mind, following are frequently asked questions about DADUs in Nashville and Davidson County at-large.


What is a DADU?

According to Nashville.gov, a detached accessory dwelling unit, (sometimes referred to as an “Accessory Dwelling, Detached”), is a detached dwelling separate from the principal structure.

Most importantly, the dwelling must be “clearly subordinate” in size, height, and purpose as compared to the principal structure. “It can be an independent structure or it can be a dwelling unit above a garage, or it can be attached to a workshop or other accessory structure on the same lot as the principal structure.” It may also be served by its own utility meter(s).

What is an accessory structure?

An accessory structure is one that is on the same plot of land as the principal structure (house), and the use of the structure is incidental to the home. Common examples of accessory structures are carports, detached garages, and storage sheds. A DADU is an example of an accessory structure. 

Why would a homeowner want a DADU?

It’s a great way to provide more livable space and enhance the value of the property.

What is the typical process for constructing a DADU in Nashville?

  1. Consider your needs and determine the primary function of the DADU.

  2. Review your zoning and zoning regulations.

  3. Determine your budget.

  4. Hire an experienced design professional and contractor.

How does zoning affect the planning process?

Zoning restrictions will impact the size or footprint of the structure you are permitted to build. There are different regulations for different zones, and those regulations can vary widely.

Also, local ordinances, historic overlays and the like can change without notice. Once you are familiar with your current zoning status, you can proceed with planning.

What size DADU should I build?

In addition to zoning, you will want to take into consideration the size and appearance of your home, to make certain that your DADU is proportional and complements the existing architecture. The size of the DADU may also be impacted by functionality.

For example, if you’re looking to add a garage, you will want to take into account storage considerations and the size of your vehicle(s). For inspiration, consider some of the garages that we have constructed.

Is a land survey necessary?

Before you begin designing or building a DADU, it’s imperative that you have civil land survey of your property. Sometimes zoning considerations effectively mandate a land survey, but even when this is not the case, you don’t ever want a scenario in which you’ve constructed a DADU, only to find out it’s on your neighbor’s property.

What is a setback, and can I build up to my property line?

A setback refers to the amount of space that is required between the structures on your property and your property line(s). There are different requirements for setbacks pertaining to DADUs as compared to setbacks from a main house. The minimum required side setback is usually at least three feet and the minimum rear setback is usually at least ten feet. But you need to verify the requirements for your property.

What is a Historic Overlay District?

This refers to a neighborhood with zoning regulations based on historical, architectural or cultural considerations. Ideally, a DADU in a historic overlay district should not only complement the existing home and property, but also mesh with the look and feel of the neighborhood.

Is there a restrictive covenant for accessory buildings located in a historic overlay district?

Yes. As noted by Nashville.gov, DADUs “are allowed in certain zones within some historic overlays.” But “before Preservation or Building Permits may be issued, the applicant shall record with the register’s office a covenant that the attached accessory dwelling is being established accessory to a principal structure and may only be used under the conditions required in [Ordinance No. BL211-900].”

What is a restrictive covenant?

In order to get plumbing, HVAC or electrical permits for a DADU you must sign a restrictive covenant, in which you agree not to use the structure in any way that is “incongruous with the current Zoning Regulations.”  The restrictive covenant must be notarized and filed with the Register of Deeds, with a recording fee payable to the Register of Deeds.

Are there plumbing restrictions that pertain to DADUs?

According to Nashville.gov, “plumbing fixtures [are] limited to a toilet and a hand sink. Showers or bathing facilities are generally not permitted within a detached structure.”

Interested in building a DADU?

If you’re interested in building a DADU on your property, Stratton Exteriors can help you navigate the zoning process and then help you visualize and accomplish your goals.

Call us at 615) 235-3803 or fill out our contact form to schedule a free consult. Or check out our featured projects and sign up for our e-newsletter to get ideas and see the quality of our work.

We’re looking forward to collaborating with you on your DADU or other home improvement project.

1. Ownership and Occupancy of Accessory Dwelling Units: A Study for Nashville, by Victoria Hensley, PhD student at Middle Tennessee State University, 2019.
By | 2019-10-07T17:18:07-06:00 October 7th, 2019|Carports and Garages|