Additional Dwelling Units, Information and Applications

An Additional Dwelling Unit, or ADU, is a dwelling unit that is either attached to the principal single-family dwelling unit, or is contained in a structure on the same parcel as the principal structure (e.g., in a garage or barn, or a standalone dwelling). 

ADUs may be allowed in most areas of La Plata County, provided the ADU complies with LUC Sec. 73-3, and fall under a few different permit types; see below to determine which type may work for your needs. If the parcel is in the Animas Valley, different requirements may apply, please give us a call.

Please be advised additional review fees may be required as part of the application process if existing structures and/or uses are found to be out of compliance with the land use code pursuant to LUC Sec. 80-8.V

Please contact the Planning Department to confirm which of these application types meets your needs prior to applying.

Director Determination ADU Permit

Administrative ADU Permit

Minor and Major ADU Permit

One single residence is allowed on a vacant legal lot of record; mobile homes, basement units, RVs and RV hook-ups, tiny homes, space over a garage, yurts, attached and detached structures may all be considered an Additional Dwelling Unit. If you are considering additional space, the following lists may help to determine if an ADU permit is required.

Additional space that would not require a Land Use/ADU permit, (does require a building permit) may include the following criteria:
  • Not a long- or short-term rental/cannot be lived in independently
  • A full bathroom
  • Bedrooms
  • An under-counter refrigerator
  • A wet bar that includes a single compartment bar sink with maximum dimensions of 15” x 15” (width/length) x 8” (depth)
  • A laundry/utility room (may contain a utility sink)
  • A standard countertop microwave oven
An ADU/land use permit would be required if:
  • the structure can be used for long or short term rental, or lived in independently from the primary dwelling.
  • the structure contains a stove/oven/range, or the supporting 240-V electric hookup or equivalent gas piping for cooking facilities.
  • the structure contains a microwave that requires an electric hookup greater than 110/120 Volts.
  • the structure contains a sink designed for use in a kitchen (based on dimensions).
  • the structure contains a kitchen.
Please note:
  • There are multiple ADU permit options, please refer to LUC Sec. 73-3 Additional Dwelling Units to learn which permit may be the most applicable to your proposal. Below you will find both a table and a flow chart image summarizing the code requirements.
  • Animas Valley Residents: If you live in Animas Valley, there are additional zoning rules pertaining specifically to granny flats; confirm your zoning classification by visiting the La Plata County GIS Mapping site or call the Planning Department.
  • Well and Cistern requirements: If the water source is a well, the issued well permit must allow for more than one dwelling. Shared wells require sharing owner signatures. An 8-hour pump and water quality testing are required. Cisterns may only be allowed if the well permit allows for more than one dwelling AND the pump test fails and/or the water quality test fails and it is not cost-effective to mitigate. If a cistern is allowed, a hauled water waiver form is required.
  • County Road Service and Road Standards: Road improvements to the private and/or county road may be required and will be the responsibility of the ADU applicant/owner. Engineer plans for road improvements are required.
Additional Dwelling Unit Permit Options & Requirements - a code summary
* This table does not apply to parcels located in the Animas Valley
Lot Size Director Determination Permit Administrative Permit Minor Permit Major Permit
5.99 acres or less        
6 - 29.99 acres  
30 - 44.99 acres    
45 - 69.99 acres  
70 - 104.99 acres  
105 acres or more