An Accessory Dwelling Unit (ADU) is a self-contained living space built on the same lot as a primary residence. In Columbia, an ADU may be built on ANY lot within a zoning district that allows a one-family dwelling in Columbia. ADUs are permitted via an administrative Zoning Permit procedure.
The application can be found at columbiact.gov/building-land-use/page/online-permitting. Generally, a Health Permit, Zoning Permit, and Building Permit will be required.
For more information click on the brochure below, or call/ email the Columbia Land Use Department
Phone: (860) 228-0440
Email: zeo [at] columbiact.org (zeo[at]columbiact[dot]org)