Lafayette Municipal Code, Chapter 6-5, Article 3 covers ADUs.

Extract:

An accessory dwelling unit shall comply with all of the following development standards:

(a) Maximum Unit Size. The living area of an attached accessory dwelling unit shall not exceed 50 percent of the existing living area of the primary unit or 1,200 square feet, whichever is less. The total living area of a detached accessory dwelling unit shall not exceed 1,200 square feet.

(c) Minimum Unit Size. The living area of an accessory dwelling unit shall be at least 150 square feet of floor area.

(d) Height in Single-Family Zoning Districts. The height of an accessory dwelling unit shall not exceed 17 feet in height or the maximum height of the primary unit, whichever is less.

(e) Height in Other Zoning Districts. The height of an accessory dwelling unit shall not exceed the height of the primary unit or the maximum height of the zoning district in which the primary unit is located, whichever is less.

(f) Setback. The setback of an accessory dwelling unit shall be the same as required in the zoning district in which the primary unit is located.

(g) Side Yards and Rear Yard. The side yards and rear yard of an accessory dwelling unit shall be the same as required in the zoning district in which the primary unit is located.

(h) Bedrooms. An accessory dwelling unit shall have no more than two bedrooms.

(i) Exterior Design. The exterior design of an accessory dwelling unit shall substantially incorporate the same exterior design of the primary unit in terms of architectural style, architectural features, building materials and colors.

(j) Passageway. No passageway shall be required in conjunction with the construction of an accessory dwelling unit. “Passageway” is defined as a pathway that is unobstructed clear to the sky and extends from to street to one entrance of the accessory dwelling unit. If a passageway or entrance is provided for the accessory dwelling unit, it shall not be located on the same side as the entrance to the primary unit. If an accessory dwelling unit is accessed by an outside stairway, the stairway shall not be on the same side as the entrance to the primary unit.

(k) Off-Street Parking. A parking space shall be at least ten feet by 20 feet, and may be open or covered.

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