This Chapter may be cited as the "Accessory Dwelling Unit Regulations."

(Ord. No. 2017-032, § 1, 1-16-2018)

A.

The intent of permitting accessory dwelling units is to provide: (i) alternative housing options to make more efficient use of existing housing stock and infrastructure, (ii) flexible use of space for property owners, and (iii) a mix of housing type that responds to changing family dynamics. Because accessory dwelling units do not require additional land, they can be incorporated into established neighborhoods more easily than other forms of housing.

B.

Irrespective of any provision in this Chapter, to the extent any PD zoning regulations regarding the creation of an accessory dwelling unit as an accessory use to any single-unit detached dwelling unit are in conflict with this Chapter 17.61, the provisions of this chapter shall govern and control.

(Ord. No. 2025-023, § 1, 7-1-2025; Ord. No. 2017-032, § 1, 1-16-2018)

As used in this Chapter, the following terms shall have the indicated meanings:

Accessory Dwelling Unit (ADU) means a dwelling unit that contains a kitchen, bathroom, facility for sleeping, and provisions for living, and is:

(i)

Located within, but is physically separated from, an existing Primary Dwelling Unit, inclusive of an attached garage;

(ii)

An addition to the Primary Dwelling Unit that is physically separated from such unit; or

(iii)

A detached structure on the same lot or tract as the Primary Dwelling Unit.

Bathroom means a room that contains a sink, toilet, and shower and/or tub.

Code means the Castle Rock Municipal Code.

Director means the Director of Development Services, or his or her designee.

Facility for sleeping means any habitable space within the ADU area that is at least seven (7) feet in dimension in length and width, and complies with all ceiling height and egress requirements of the international residential code for one- and two-family dwellings, as adopted pursuant to Section 15.06.010 and amended by Section 15.06.030 of this Code.

Kitchen means an area used for the preparation of food and includes a stove, cooktop, range, oven, or any combination thereof, and either one or more 220-volt or greater electrical outlets or a gas line connection.

Primary Dwelling Unit means a separate dwelling unit that is the larger of the dwelling units on a lot or tract that contains an Accessory Dwelling Unit.

Provisions for living means the existence within an ADU of permanent working utilities, such as domestic water, sanitary sewer, electricity, and gas (as necessary for cooking and/or heating).

(Ord. No. 2023-007, § 21, 4-4-2023; Ord. No. 2017-032, § 1, 1-16-2018)

A.

Accessory Dwelling Units must comply with all provisions of this Chapter 17.61 and any applicable PD zoning regulations. In the event of a conflict between this Chapter and the PD zoning regulations, the more permissive provision(s) shall apply.

B.

Accessory Dwelling Units are prohibited in:

1.

Any MH Manufactured Home Zone District, or

2.

Any residentially zoned property that contains an existing/proposed duplex, triplex, condominium, townhome, or multifamily dwelling.

C.

Accessory Dwelling Units are allowed in all residential zone districts and in any area within a Planned Development District designated for single-family residential uses upon an administrative review by the director and approval of a building permit.

(Ord. No. 2025-023, § 2, 7-1-2025; Ord. No. 2023-007, § 22, 4-4-2023; Ord. No. 2017-032, § 1, 1-16-2018)

A.

Criteria. In order to be classified as an ADU, a structure must meet each of the following building criteria:

1.

Provisions of living;

2.

A kitchen;

3.

A bathroom;

4.

A facility for sleeping; and

5.

Physical separation from the primary dwelling unit, as follows:

a.

A detached ADU is presumed to have physical separation for the purposes of this section.

b.

When an ADU is attached to the primary dwelling unit, physical separation is required between the primary dwelling unit and the ADU. Such physical separation may be accomplished with a wall, a wall with a door, or other similar feature. Where a wall exists, the presence of a door frame, door hinges, pocket, or an opening equal to or less than thirty-eight (38) inches in width shall constitute physical separation.

B.

A building permit meeting all Town regulations must be obtained for all construction activities associated with developing Accessory Dwelling Units.

C.

The Town may issue a building permit authorizing the construction and use of an Accessory Dwelling Unit, provided the following conditions apply:

1.

Number. No more than one (1) ADU may be created or maintained on a single lot or tract.

2.

Owner Occupancy. The owner of an existing primary dwelling unit, as evidenced in the Douglas County public records, must demonstrate that such owner resides in the primary dwelling unit at the time an application is submitted for a building permit for construction of an ADU.

3.

Short-term rentals. Nothing in this Chapter 17.61 shall preclude the town from enacting or applying a local law regulating the use of Accessory Dwelling Units for short-term rentals.

4.

Subdivision. Accessory Dwelling Units may not be subdivided or otherwise conveyed into separate ownership from the Primary Dwelling Unit on the lot or tract.

5.

Utilities.

a.

No separate water or sewer taps will be allowed for the ADU.

b.

All billing for water, sewer and storm water services will be billed to the Primary Dwelling Unit account holder. As a condition to issuance of a building permit, the account holder shall certify to the Town that they will be responsible for all utility charges incurred by the ADU.

c.

Should an ADU require the enlargement of the Primary Dwelling Unit's existing water tap, the applicant shall pay the incremental System Development Fees (as set forth in Chapter 13.12 of the Code) based on the new tap size, together with any connection fees.

6.

HOA Compliance. It shall be the obligation of the property owner to obtain compliance with any homeowner association requirements for the ADU. The Town will not independently verify such compliance.

7.

Design. An ADU shall be designed to maintain the architectural design, style, appearance and character of the Primary Dwelling Unit, and must be consistent with the existing façade, roof pitch, siding, eaves, window treatment and color of the Primary Dwelling Unit. The ADU shall be permanently affixed to an engineered foundation. All district zoning regulations applicable to the construction and placement of structures shall apply to ADUs.

8.

Size. The floor area of an ADU located interior to the Primary Dwelling Unit, whether as part of, or as an addition to the Primary Dwelling Unit, shall not exceed fifty percent (50%) of the Primary Dwelling Unit or seven hundred fifty (750) square feet, whichever is greater. A detached ADU shall not exceed an eight hundred (800) square foot building footprint attributable to the ADU, unless applicable PD zoning regulations establish a more permissive limitation, in which event the PD zoning regulations governing size shall apply.

9.

Side setback. The side setback of an ADU shall meet the side setback requirements for an accessory structure in the applicable zone district or PD zoning regulations; provided, however, that if the side setback requirements for an accessory structure are greater than those of the Primary Dwelling Unit, the side setback of an ADU shall be equal to that of the Primary Dwelling Unit.

10.

Rear setback. The rear setback of an ADU shall meet the rear setback requirements for an accessory structure in the applicable zone district or PD zoning regulations. if, however, no rear accessory structure setback requirements exist, then the rear setback of an ADU shall be five (5) feet.

11.

Entrance. If an ADU is created by an addition to an existing Primary Dwelling Unit that requires a new separate outside entrance, only one (1) entrance may be located visible from the street upon which the property is addressed. The additional entrance may be located on the side of, or in the rear of the Primary Dwelling Unit.

12.

Deviation from stated conditions. A request for deviation from the applicable regulations to install features that facilitate access and mobility for disabled persons shall be considered by the Board of Adjustment pursuant to Chapter 17.06 of the Code.

13.

Pets. The restriction on the number of animals allowed under the Code shall be per lot, irrespective of the number of dwelling units located on the lot.

14.

Prohibition. Mobile homes, recreational vehicles, travel trailers and other motor vehicles, attachments, and accessories are prohibited as Accessory Dwelling Units.

(Ord. No. 2025-023, § 3, 7-1-2025; Ord. No. 2023-007, § 23, 4-4-2023; Ord. No. 2017-032, § 1, 1-16-2018)

A prior legal nonconforming ADU shall be governed by Chapter 17.16 of the Code.

(Ord. No. 2017-032, § 1, 1-16-2018)

A.

Any person who violates any of the provisions of this Chapter shall be punished by a fine of not more than one thousand dollars ($1,000.00).

B.

Each such person shall be guilty of a separate offense for each and every day during any portion of which any violation is committed, continued or permitted by any such person.

C.

In addition to receiving any fines or other monetary remuneration, the Town shall have the right to seek injunctive relief for any and all violations of this Chapter and all other remedies provided at law or in equity.

(Ord. No. 2017-032, § 1, 1-16-2018)