Growth FAQ - Planning & Zoning

Can I build an accessory dwelling unit on my property?

Accessory dwelling units are often stand alone residential units of limited size in a side or rear yard. They're sometimes known as granny flats. They are of interest to many people who want to care for older relatives in their home, but with the extra privacy that a separate unit affords. They're also of interest to persons who want to rent them as an extra source of income. The American Planning Association has a helpful discussion of accessory dwelling units.

Sec. 10-412(1), TLDC allows ADUs in all zoning districts if all the following requirements are met:

• No more than one ADU is permitted on any lot;
• An ADU is an accessory structure to the principal structure;
• The ADU's height is not greater than the principal structure (unless it is above a garage);
• Detached ADUs shall be in the side or rear yard;
• ADU size shall not exceed 40% of the area of the principal structure.
• An ADU of 500 square feet is allowed for all lots with a single-family residence, provided that it can meet all other development standards.
• ADUs shall not exceed 800 square feet gross floor area when accessory to single-family structures; or 1,000 square feet gross floor area when accessory to retail, office, and industrial principal structures.
• The ADU can't interfere with the appearance of the principal structure.
• ADUs must use similar building materials as those of the principal structure.
• ADUs must meet the setbacks and lot coverage requirements of the principal structure.
• The rooming house requirements of Sec. 10-83, TLDC apply to lots with ADUs zoned RP-1, RP-2, R-1, and R-2.