Accessory Dwelling Unit (ADU) Permit in Glenwood Springs, Colorado

Glenwood Springs requires an accessory dwelling unit (adu) permit for: ADU is allowed in most residential zone districts, allowed by right within a historic district only when internal to an existing residential dwelling or existing accessory structure, and allowed within a PUD unless specifically prohibited by the PUD; Only one ADU permitted per parcel; ADUs may only be established on a lot where a detached single-family dwelling exists or will be built concurrently; Gross floor area (living area) must be no less than 300 sq ft and no more than 1,000 sq ft, AND must not exceed 55% of the principal dwelling's floor area (a narrower exception allows up to 50% of an existing structure's footprint, including basement, for ADUs converted within an existing home); Living area for this calculation excludes exterior wall thickness, garage areas, basement areas under 6 ft ceiling height, and any area under 5 ft ceiling height or not accessible by stairway; Detached ADU height may not exceed 27 feet, nor the height of the principal single-family residence, nor the zone district's maximum building height, whichever is most restrictive; One off-street parking space (9 ft x 19 ft) required per ADU, in addition to parking required for the principal dwelling (properties in the General Improvement District are exempt from this requirement); Detached ADUs generally must be sited in the rear or side yard of the principal dwelling, with a narrow front-yard exception (primary structure within 15 ft of rear lot line, or ADU proposed within/on top of an existing legally conforming garage without increasing footprint); New-construction ADUs must incorporate at least 2 architectural features (of an enumerated list) per side to meet the 'four-sided design' compatibility standard; colors, materials, and design must be substantially the same as the principal dwelling; Properties with average slope of 20%+ (Hillside Preservation Zone) require special review with a public hearing before the Planning and Zoning Commission; Two-step permitting process: (1) ADU Permit application with architectural plans reviewed by Planning; (2) standard building permit with structural/floor plans reviewed by the Building Department; Electrical work on an ADU is likewise permitted and inspected by the State of Colorado, not the City, consistent with all other electrical work citywide. If your project isn't listed, confirm with City of Glenwood Springs Building Department (Community Development Department) at 970-384-6450 before starting work.

In Glenwood Springs, the published Building Permit Fee (same valuation-based Table 1-A as new construction) is: $23.50 minimum, scaling per Table 1-A valuation tiers. Additional published fees: Water Improvement Fee (System Improvement Fee) — ADU — 25% of the fee charged for a single-family house; Sewer Improvement Fee (System Improvement Fee) — ADU — 25% of the fee charged for a single-family house; Park Land Dedication Fee — ADU — System Improvement Fees page cites $5,300 for an ADU generally (2026 general estimate); School Land Dedication Fee — Not charged for ADUs. These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Glenwood Springs does not publish a plan-review timeline for this permit. Contact City of Glenwood Springs Building Department (Community Development Department) at 970-384-6450 for current turnaround.

You'll need: ADU Permit Application (Tyler EnerGov Customer Self-Service Portal); Architectural Plans, Site Plan, Landscape Plan, Floor Plans, Elevations; Building Permit Application. Depending on your project, Glenwood Springs may also ask for: Subdivision Plat. See the required-documents checklist on this page for details on each.

Glenwood Springs requires 4 inspection(s) for an accessory dwelling unit (adu) permit, in order: Foundation, Rough Framing, Rough Plumbing / Mechanical, Final Inspection and Certificate of Occupancy. Schedule each through City of Glenwood Springs Building Department (Community Development Department) (970-384-6450).

Apply through City of Glenwood Springs Building Department (Community Development Department) at 101 W. 8th Street, Second Floor, Glenwood Springs, CO 81601. Phone: 970-384-6450, email: Building@cogs.us. Office hours: Glenwood Springs City Hall Hours: 7:30 AM to 5:30 PM, Mondays-Thursdays (closed Fridays), per the City's Contact Us footer. Building Department direct line 970-384-6450; Fax 970-945-8582; Inspection Line (24-hour automated request system) 970-384-6432; Building Official Victor Meraz, 970-384-6410.. Official information: https://www.cogs.us/283/Building-Department.

An ADU must be no less than 300 sq ft and no more than 1,000 sq ft of living area, AND must not exceed 55% of the principal dwelling's floor area (whichever limit is more restrictive governs), per Municipal Code §070.030.040. A narrower exception allows up to 50% of an existing structure's footprint for ADUs converted within an existing home.

No. Only one accessory dwelling unit is permitted per parcel in Glenwood Springs.