City of Charlotte RIO: Residential Infill Overlay District Regulations

The RIO: Residential Infill Overlay District modifies City of Charlotte base zoning by imposing stricter controls on building scale, including a 20-foot default sidewall height limit and a 45-degree height plane requirement. It further regulates neighborhood character by requiring front setbacks to align with the average of the two closest neighboring homes and limiting the maximum heated square footage of new residences based on existing blockface averages or a calculation of 800 square feet per dwelling unit.

Purpose and Applicability of the RIO District

The RIO: Residential Infill Overlay District is intended to facilitate residential infill development within the City of Charlotte’s Neighborhood 1 Zoning Districts (specifically N1-A, N1-B, N1-C, N1-D, and N1-E). The primary goal of the RIO: Residential Infill Overlay District is to ensure that new construction maintains and complements existing neighborhood patterns and scales through specific controls on height and dwelling unit size [Section 14.5.A].

The RIO: Residential Infill Overlay District applies only to single-family, duplex, and triplex dwellings. It does not apply to nonresidential development [Section 14.5.B.3]. Additionally, the City of Charlotte prohibits the application of the RIO: Residential Infill Overlay District in combination with the Historic District Overlay (HDO), Streetside Historic District Overlay (HDO-S), or the Neighborhood Character Overlay (NCO) [Section 14.5.B.2].

Modifications to Base Standards

The RIO: Residential Infill Overlay District replaces the standard dimensional requirements of the underlying City of Charlotte zoning districts with the following specialized metrics:

Standard	RIO: Residential Infill Overlay District Requirement
Front Setback from Street	Must be the average of the two closest residential buildings on the same blockface, with a minimum of 10 feet [Section 14.5.C.1.a].
Default Max Sidewall Height	20 feet [Section 14.5.C.1.b].
Sidewall Height Adjustment	May be increased above 20 feet to match the average height of the facing sidewalls of buildings on both sides of the lot [Section 14.5.C.1.b].
Building Height Plane	A 45-degree plane established starting from the maximum permitted sidewall height at the required minimum side setback [Section 14.5.C.1.c].
Max Building Size	The greater of: (A) The average single-family dwelling size on the subject blockface; OR (B) The number of units multiplied by 800 square feet [Section 14.5.C.1.d].
Single-Family Size Bonus	Single-family dwellings may exceed the maximum building size calculation by 25% [Section 14.5.C.1.d].

Front Setback and Sidewall Height

In the RIO: Residential Infill Overlay District, the City of Charlotte requires a survey of the setbacks of the two closest residential buildings on the same blockface at the time of permitting to determine the required front setback [Section 14.5.C.1.a].

Regarding sidewalls, the height is measured from the finished floor elevation at the ground floor to the eave or the bottom of the finished roof plane. If no residential buildings exist on the same blockface as a new building under development, the base maximum building height of the City of Charlotte zoning district controls [Section 14.5.C.1.b].

Building Height Plane

The City of Charlotte uses the building height plane in the RIO: Residential Infill Overlay District to manage the "bulk" of a structure as seen from neighboring properties. While the plane starts at the side setback, it allows for one additional foot of height for every one foot the structure is moved further away from the required side setback. Dormers and gable ends are permitted to extend through this 45-degree plane, provided their cumulative width does not exceed 25% of the depth of the sidewall [Section 14.5.C.1.c].

Maximum Building Size

The maximum building size in the RIO: Residential Infill Overlay District is calculated based on total heated square footage. When using the "blockface average" method, the applicant must furnish City of Charlotte or Mecklenburg County tax records to document the average size of existing single-family dwellings on that specific blockface [Section 14.5.C.1.d].

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