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Accessory Dwelling Unit

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An Accessory Dwelling Unit (ADU), sometimes called an "in-law apartment" or "carriage house," is typically an additional housing unit within, or on the same lot as, a single-family home with entries and amenities that are separate from the primary residence. Please review the information below to see what's required for different types of ADUs before submitting your application.

Getting Started

Review the list of required documents and steps below before beginning the application process.  Once you are ready to apply, you will login to our permitting system, www.arvadapermits.org, enter the required information and upload PDF plans and related documents to your application.  

 

  eTRAKIT Online Application

 

Types of Accessory Dwelling Units

The City of Arvada has three categories for Accessory Dwelling Units (ADU) more details about these categories are listed below. If your address is in a Homeowner's Association (HOA) you must gain approval from the HOA in addition to permits and approvals from the City of Arvada. An approval and permit issued by the City of Arvada does not overrule HOA approval.

Type A

An Accessory Dwelling Unit which is detached from the principal dwelling.  It is considered lockable and rentable.

Type B

An Accessory Dwelling Unit with the following characteristics:

  • Located inside a single family dwelling, or
  • Attached to a single family dwelling
  • Whose occupants and the occupants of the principal dwelling do not live together as a single household unit and which is rented.
  • Typically have a separate access from the principal dwelling.
  • Which is locked off from the principal dwelling.

Both Type A and B Accessory Dwelling Units are considered a separate dwelling unit under the building code.  Fire separations and a separate HVAC system are required.

Type C

An Accessory Dwelling Unit with the following characteristics:

  • Located inside a single family dwelling, or
  • Attached to a single family dwelling.
  • Whose occupants and the occupants of the principal dwelling live together as a single household unit and which is neither rented nor locked off from the principal dwelling.

The Type C Accessory Dwelling Unit and principal dwelling shall be considered part of one dwelling unit under the building code. The HVAC system may be shared and fire separation requirements are treated differently.

Who Can Do the Work?

ADU type A and B permits are issued to Licensed Contractors with a type 1B or 2B license, ADU Type C can be issued to the homeowner or a contractor. If applying as the homeowner, you must own and live on premise and must be completing the work. To ensure your permit is issued in a timely manner please make sure to submit the correct documentation for all subcontractors. Permits without sub-contractors listed will be placed into a hold and will not be allowed to start construction. Please review contractor qualifications prior to submitting your application.

Zoning Requirements

While the City of Arvada allows ADUs in all residential zone districts, each zone district has different development standards as far as the maximum lot coverage you are allowed, and where structures can be located on individual lots. Please use this link to find your zone district, and compare it to this table to find your development standards. In addition, while the City allows ADUs in all residential zone districts, some Home Owners Associations (HOAs) prohibit ADUs. If your home is part of an HOA, you will need HOA approval before the City can issue a permit.

Review Timelines

The City of Arvada is committed to providing plan reviews within our timelines, however, workload of the current development environment in the City of Arvada can affect these timelines. Complete submittals will help with keeping within this timeframe. If your application package is incomplete your project may not be accepted and can cause delay in approving your application.

Review timeline for ADU permits
Type Review Time Required
A 3-4 weeks
B 1-2 Weeks
C Counter Review (30-40 minutes) depending on permit demand

Required Submittal Documents

Permit applications that are submitted with complete information will be reviewed. If you have questions about items that are required please contact buildingpermits@arvada.org.