Grand Rapids

Planning Staff Report
Approved with Conditions
Aug 9, 2018 12:00 PM

(1:50 p.m.) 537 Shirley St. NE--Accessory Dwelling Unit


Department:Planning StaffSponsors:
Category:Public Hearing

Content A


537 Shirley Street NE


Adam Tauno Williams


Approval to construct a detached accessory dwelling unit. 


TN-LDR (Traditional Neighhborhood-Low Density Residential)


Article 5               Residential Zone Districts


5.9.03.              Accessory Dwelling Units

5.12.08.E.              Standards for Site Plan Review

5.12.09.              Special Land Uses

Case Number:


Staff Assigned:

Elizabeth Zeller

Type of Case:

Special Land Use

Effective Date:

August 25, 2018


Content C


·         The applicant requests approval to demolish an existing detached accessory building and construct a new two story garage with second floor accessory dwelling unit (ADU) floor.

·         Accessory dwelling units currently require Special Land Use approval in all residential zone districts.


Surrounding Zoning and Land Uses

North:              TN-LDR              low-density residential

East:              TN-LDR              low-density residential

South:              TN-LDR              low-density residential

West:              TN-LDR              low-density residential


Master Plan

The Master Plan designates this area as Medium Low Density Residential.


Accessory Dwelling Units

·         An Accessory Dwelling Unit is a secondary and subordinate dwelling unit that is included within an accessory structure, contained within a detached single-family dwelling, or separate from but located on the same lot as a detached single-family dwelling. 

·         ADUs do not count toward maximum residential density and may be permitted as a Special Land Use. 


Site and Building Information

·         The property is 5,816.25 sq. ft. in area and is located on the north side of Shirley Street, east of College Avenue.  The property is served by an alley to the rear.

·         The existing single-family home on the property has a gross floor area of +/-2,245 sq. ft. The existing detached garage is +/-320 sq. ft.

·         The proposed new structure will be two stories and have a footprint of 22’ x 26’ (572 sq. ft.). 

·         The structure will be located 5’ from the westerly lot line and 3’ from the rear lot line at the alley, meeting required setbacks for accessory structures. 

·         The ground floor of the new structure will have alley access, accommodate parking for a single car, include a storage area, and house the staircase to the second floor. 

·         An asphalt parking pad accessed from the alley will accommodate an additional vehicle.  It will be located 3’ from the side lot line.

·         The second story ADU will have one bedroom, one bathroom, and a combined kitchen and living area.

·         The new structure will be finished to match the materials and style of the primary structure, using vinyl siding to match the color of the house.

·         An additional 9’ wide overhead door is proposed toward the interior of the site. 

·         Minimum required green space for the zone district (40%) will be met.

·         The structure will be approximately 21’6” at the midpoint of the roof. 


Accessory Dwelling Units Use Regulations (Section 5.9.03.)

ADUs are subject to additional standards, which may be waived or modified by the Planning Commission. The proposed ADU meets all standards except for the size standard of 5.9.03.F., for which a waiver is requested.


Section 5.9.03. Accessory Dwelling Units

Compliance as proposed.

Not more than one (1) Accessory Dwelling Unit (ADU) may be included within a detached single-family dwelling (primary dwelling unit), or accessory structure, or separate from but located on the same lot as a detached single-family dwelling.


If separate from the primary dwelling, the Planning Commission shall take into consideration the relationship of a detached ADU to other surrounding residential structures as part of the Special Land Use review. 

The detached structure is located at the rear of the property, located adjacent to other detached garages.


The proposed structure differs from nearby accessory structures in that it is two stories in height.

Minimum Lot Area. A minimum lot area of five thousand (5,000) square feet is required.

OK. The property has an existing detached single-family house and is ~5,816.25 sq. ft. in area. 

Residential Density. The ADU shall be excluded from maximum residential density requirements.


Building Height. The portion of a single family detached dwelling with an ADU, when newly added, shall not exceed the permissible main building height of the Zone District. The Planning Commission may increase the height of an accessory structure occupied by an ADU up to a maximum of twenty-five (25) feet.

OK.  The proposed structure is approximately 21’6” in height.

Front Yard Prohibited. The ADU may not be located within the front yard.


Minimum/Maximum ADU Size. The ADU shall not exceed twenty-five (25) percent of the gross floor area of the primary dwelling unit, but in any case shall be at least four hundred (400) square feet and not larger than eight hundred fifty (850) square feet in gross floor area.

Including the basement, the floor area of the house if +/-2,245 sq. ft., yielding a maximum ADU of 561 sq. ft. 


A waiver is requested to allow an ADU of 572 sq. ft.

Bedroom Maximum. A maximum of two (2) bedrooms are permitted within an ADU. Occupancy shall be limited to no more than two (2) persons.


OK. One bedroom is proposed. 

Owner Occupancy. One (1) of the dwelling units shall be owner-occupied. If the ADU is used for lease, it shall be registered with the City as required in Chapter 140 of the City Code.

OK. The primary residence is intended to be occupied by the owner and the proposed ADU is intended to be occupied by a family member. 


However, the Planning Commission can require as a condition of approval that the ADU be properly registered and certified should the applicant decide to lease the unit.

Leasing or Rental. No ADU shall be leased or rented for less than thirty (30) days, or to more than eleven (11) different parties in any calendar year.


OK. This would be required as condition of approval should the Planning Commission approve the request.

Alterations or New Construction. Any alterations to existing buildings or structures or the construction of a new structure to accommodate the ADU shall be designed to maintain the architectural design, style, appearance and character of the main building as a detached single-family dwelling, including but not limited to entrances, roof pitch, siding and windows.


OK. The new garage housing the ADU will be architecturally compatible with the appearance and character of the main building.

Deed Restriction. A deed restriction enforceable by the City shall be recorded prior to the issuance of a building permit stipulating that the ADU will not be conveyed separately from the primary dwelling unit. An alternative form of security may be substituted if it meets the intent of this provision and is approved by the City Attorney.

OK. This would be required as condition of approval should the Planning Commission approve the request.



·         Two parking spaces are required for the single family home; one additional parking space is required for the ADU.  A total of three parking spaces are required.

·         A total of two parking spaces are proposed. 

·         Parking is deficient by one space. 

·         The Planning Commission has the discretion to reduce the parking requirement using on-street parking to meet a portion of the off-street parking requirements, provided

o       Adequate on-street parking exists within five hundred (500) linear feet of the primary entrance of the main building;

o       No more than fifty (50) percent of the off-street parking space requirement is met through the use of on-street parking;

o       The intensity of the use and its parking requirements shall not substantially adversely affect available parking for surrounding uses; and

o       There are no adverse effects on existing or planned traffic circulation patterns.


Neighborhood Input

·         Several emails in support of this request have been received.

·         One email in opposition has been received.


Key Considerations

·         Neighborhood concerns, if any.

·         Compatibility of an accessory dwelling unit in this neighborhood and relative to the adjacent properties. 

·         Additional height required to accommodate a two-story accessory structure to house the ADU.

·         Parking deficiency.