Accessory and Secondary Dwelling Units in Fort Worth

In the City of Fort Worth, accessory dwelling units (ADUs) are defined as non-rented living spaces for family or guests that do not contain cooking equipment, while independent "second units" are permitted primarily in denser residential and mixed-use districts. Two detached dwelling units are allowed on a single lot within the City of Fort Worth Two-Family (B) District and various form-based districts, provided they maintain a 10-foot separation and provide independent paved driveway access for each unit. Habitable accessory structures in one-family districts are strictly prohibited from being used as independent residences or containing kitchens.

Accessory Dwelling Units (ADUs) vs. Secondary Units

The City of Fort Worth Zoning Ordinance makes a legal distinction between a "Habitable Accessory Building" and a "Secondary Dwelling Unit."

Accessory Dwelling Units (ADUs): These are considered habitable accessory structures. They are permitted in most residential districts in the City of Fort Worth but are restricted to occupancy by family members or temporary guests. They cannot be rented as independent residences and, by definition, must not contain cooking equipment [Section 9.101].
Secondary Dwelling Units / Second Units: These are independent, rentable residences located on the same lot as a primary home. These are only permitted in specific districts, such as the Two-Family (B) District or various Mixed-Use and Urban Residential districts [Section 4.707, Section 4.1203].

Districts Permitting Secondary or Multiple Units

The following districts in the City of Fort Worth explicitly allow for a second independent dwelling unit or a secondary dwelling unit on a single lot:

District Type	Specific Zoning Districts	Permission Level
Two-Family	Two-Family (B) District	Permitted (Attached or Detached)
Urban Residential	Urban Residential (UR) District	Permitted (Detached)
Mixed-Use	MU-1 and MU-2 Districts	Permitted (Attached or Detached)
Near Southside	NS/T4R, NS-T4, NS-T4N, NS/T5	Permitted (Detached)
One-Family	A-5, A-10, A-21, etc.	ADUs only (Non-rentable, no kitchen)

Two-Family (B) District Standards

The City of Fort Worth Two-Family (B) District allows for four distinct housing configurations that involve multiple units on one lot:

Two attached units on a single lot.
Two detached units on a single lot.
Detached zero lot line units.
Attached zero lot line units [Section 4.707].

Technical Standards for Detached Units

When the City of Fort Worth permits two detached dwelling units on one lot (primarily in the "B" District or via specific mixed-use allowances), the following development standards apply:

Standard	Requirement
Building Separation	Minimum of 10 feet between the two units [Section 6.502].
Access	Ingress and egress must be provided via paved driveways [Section 6.502].
Back-up Turn-around	Required if one unit is located behind the other [Section 6.502].
Parking	One parking space must be provided adjacent to each unit [Section 6.502].
Landscaping	All yards must be planted in ground cover except for building/driveway footprints [Section 6.502].

Habitable Accessory Structure Regulations

For homeowners in the City of Fort Worth One-Family districts (such as A-5 or A-10) who wish to build an ADU for family or guests, the structure must meet these requirements:

Size Limitation: The accessory structure cannot have a greater square footage than the primary structure [Section 5.300].
Height: The height of the accessory structure may not exceed the height of the primary residence [Section 5.301].
Location: The structure must be located behind the rear wall of the primary residential structure and be at least 75 feet from the front property line [Section 5.301].
Utility Meters: The ADU must connect to the utilities (water, electric, gas) of the primary structure and receive service through the same meters [Section 5.300].
Cooking Equipment: The definition of an accessory dwelling unit in the City of Fort Worth specifically excludes the installation of cooking equipment [Section 9.101].

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