In 2026, Denver’s zoning laws for Accessory Dwelling Units (ADUs) require homeowners to adhere to specific dimensional and occupancy standards. The city generally allows ADUs in most residential zones (R-0 through R-4), provided the property meets the following criteria:

• Lot Size Requirements: Attached ADUs require a primary lot size of at least 5,000 square feet, while detached structures (such as garage conversions) require a minimum lot of 6,000 square feet.
• Height and Setbacks: Detached ADUs are capped at a maximum height of 24 feet. All setbacks must align with the requirements of the underlying zone for the primary residence.
• Parking: The city mandates one off-street parking space, though exemptions may apply if the property is located in a reduced-parking zone or near high-frequency transit.
• Owner Occupancy: Denver requires owner occupancy for at least one of the units on the property for the first three years after the conversion.
• Permitting Process: All projects must be submitted through the Denver ePermits portal. The application must include a site plan, floor plan, elevations, energy calculations, and a signed owner-attestation form.