Accessory Dwelling Unit (ADU)

Miami-Dade County has approved an ordinance providing for the addition of an Accesory Dwelling Unit (ADU) or guesthouse in a single-family zoned district, either as a newly detached (standalone) or attached dwelling, including the conversion of a portion of an existing single-family dwelling. It provides some restrictions to ensure surrounding area compatibility, design compatibility, and the management of parking needs.

An ADU is defined as an attached or detached accessory building or portion thereof, that is used as an ancillary residential unit and is located on the same lot as the principal single-family dwelling; it has a separate kitchen, bathroom, and sleeping area; and is intended for use by a separate family of occupants. Charging a fee, such as rent, to use an ADU separately from the principal dwelling shall not constitute unlawful duplex or multiple-family use.

A guesthouse is an attached or detached accessory building, or portion thereof, that is used as an ancillary residential unit, is located on the same lot as the principal single-family dwelling and is intended for use by only the occupants of the principal structure and their family and is not rented for a fee.

You may apply for a Certificate of Use for an ADU via the Portal. In addition to zoning and lot size requirements, you will also need to comply with and consider the following:
- Only the owner of the property may obtain a CU for an ADU
- A completed ADU owner disclosure statement is required for all ADU applications
- Minimum and maximum floor area requirements
- Building code requirements
- Location on the lot
- Appearance standards
- Parking
- Impact fees required
- Use is limited to one ADU on the property, and the use must be ancillary
- Occupants do not have to be the family of the occupant of the primary structure
- Can be rented for a fee
- ADU may be attached or a detached (standalone) structure
- ADU can have a separate address, entrance, and/or separate utilities from the principal structure
- If ADU is detached, the height of the structure cannot exceed the height of the principal structure
- Setback requirements still apply for detached structures
- An RV cannot be used as an ADU
- One accessory unit per lot shall be permitted in the following zoning districts located inside of the Urban Development Boundary: AU, EU, and RU, as well as GU for properties that are trended to AU, EU, or RU.
- Lot size must be a minimum of 7,500 sq. ft.
- Accessory dwelling size must be between 400-800 Sq ft in RU-1 districts
- Certificate of Occupancy (COU) is required, assuring the structure is legal and shall not be undergoing construction to obtain a COU
- Overnight occupancy is a maximum of two persons per bedroom, excluding children under three years of age
- For guesthouses, the occupancy is limited to the family, as defined in section 33-1, that occupies the principal dwelling.
- Parking requirement is a maximum of one additional parking space and not more than two vehicles used by occupants of the ADU; parking must be within the same property or in the adjacent swale
- Vacation Rentals: Areas assigned for an ADU, or a guesthouse cannot be used as vacation rentals on their own. The vacation rental must be for the entire property
- Zoning Review includes an administrative site plan review
- Homes that belong to a Community Association (HOA’s) need proof of notification to a homeowner’s association
- Neighborhood Characteristic: The principal structure has the same exterior finish and roof style as the principal structure
- Detached units may not be in front of the principal structure
- The property owner cannot live in the ADU or guesthouse
- Only the owner of the property may obtain a CU for an ADU, which would be a renewable CU
- Information for occupants of an ADU must be updated when occupancy changes or upon CU renewal
- Inspections: One-time interior inspection, and exterior inspections required for CU renewals
- The CU for an ADU must be renewed, whether the unit is being rented or not
- Setback requirements still apply for detached structures
- Converting an ADU into a guesthouse can be done if the CU is updated and the declaration for a guesthouse is submitted.

Need CU Assistance?

You must register and create an account through the online appointments and queue portal (MeetQ) to consult with staff. Consults may be scheduled in person, by phone or virtually on the specified days and times listed on the MeetQ homepage for Certificate of Use. For further assistance, you may contact RER-CUINFO@miamidade.gov or call 786-315-2660.