Accessory Dwelling Unit (ADU)

Q:  What is an ADU? 

A:  An apartment integrated within a single-family dwelling unit, above a garage located on the single-family lot, or as a detached unit located behind the single-family structure. Accessory dwellings typically have separate bathrooms, eating facilities, living areas, and entrances from the single-family and may or may not have separate utilities and shall not exceed 50 percent of the floor area of the single-family dwelling unit. There shall not be more than one accessory dwelling located on a lot in addition to the single-family dwelling unit and the accessory dwelling shall not be subdivided or sold separately from the single-family dwelling unit. 

Effective June 1, 2017, the Town of Gypsum Municipal Code requires the permitting of all existing ADUs and are accepting applications for new ADU builds to be constructed.  It is of utmost importance to ensure the safety of our community by ensuring proper ADU guidelines and requirements that help protect our residents and homeowners. 

**Effective January 1, 2018, existing ADUs that have not submitted ADU Permit Application will be in violation of Title 18 of the Town of Gypsum Municipal Code.  ADUs found to be leased without an ADU Permit may result in both owner and tenant fines and/or removal of legal ADU status for up to three years.

Title 18
 of the Gypsum Municipal Code - Accessory Dwelling Units (ADU). 

Existing ADUs

  • Application fee $250
  • Applications are currently being accepted / To assist with volume, areas will be broken out into zones and specified zone periods will focus on a specific area.  Residents within each zone will be notified.  (See Properties by Zone link) 
  • You will need: Site plan showing property, buildings, landscaping, driveway(s) and/or parking, Sketch Plan showing ADU floor plan (windows, doors, access) along with Photos of ADU entry, showing location of ADU within the property, kitchen, bath, bedrooms, etc... (Size of existing unit will be grandfathered)
  • Inspection by a town building official is required: Smoke alarm, carbon monoxide detector, safe stairs and handrails, egress windows and doors, working kitchen and working bathroom(s).
  • Existing ADU properties with owners living offsite prior to May 1, 2017 (Grandfathered) 

New ADUs

  • Application Fee $250
  • Applications are currently being accepted
  • You will need: Site plan, floor plan, elevations, etc...
  • ADU is limited to 800 square feet of livable area within a lot size of 6,500 square feet or larger.
  • Inspection by a town official is required, as with all new construction.  ADU build inspection will be required to be completed along with the Single Family structure inspection.  
  • Property owner must live on-site 

All ADUs

  • Not allowed in multi-family (duplex, townhome, etc...) or mobile home parks
  • Only 2 cars per ADU will be allowed and must be on-site in garage or driveway (See exception for on-street parking) 
  • If the town does not provide water and/or sewer services to the property, applicant shall provide proof that ADU will be serviced by septic or well
  • A monthly fee of $6.25 for water and $6.00 for sewer will be added for services 
  • Must have separate trash services ($80 for container & $15/mo. service fee)
  • Mobile homes, travel trailers, and recreational vehicle are not prohibited for use as an ADU


ADUs not properly permitted will be investigated for violations and enforced per the Gypsum Municipal Code.  Sections 8.04.010, 8.04.070(a), 18.02.040, 18.07.010., and 18.10.040.  **If an ADU is found to be leased without a permit, both owner and tenant may be fined.