MU-MC District Setback and Alley Access Standards
In the MU-MC district, a zero-foot setback is allowed for property lines abutting an alley if at least 24 feet of backup space (including the alley) is provided. While a 5-foot setback is required when immediately adjacent to residential property, this adjacency rule typically does not apply to property lines separated by an alley. Building separation remains 10 feet.
In the Mixed-Use Midtown Commercial (MU-MC) district, building setbacks are primarily governed by their relationship to the street, adjacent residential properties, and existing alleys. While specific residential adjacency rules exist, they are applied based on whether a property line is shared directly with a residential zone or is separated by a right-of-way such as an alley.
Side and Rear Setback Requirements
Under the general lot and building standards for the MU-MC district, the minimum requirements for side and rear setbacks are as follows:
- Standard Setback: 0 feet [§ 18.02.312, Table 2-25].
- Residential Adjacency: If a building is located immediately adjacent to the MU-RES (Mixed-Use Midtown Residential) district or any other residentially zoned property, the minimum setback is increased to 5 feet [§ 18.02.312, Note 7].
- Building Separation: There must be a minimum of 10 feet between principal buildings on the same site [§ 18.02.312, Table 2-25].
Alley Access and the Zero-Foot Setback Allowance
The code provides a specific allowance for property lines that abut an alley. A minimum zero-foot setback is permitted, even if the property is in proximity to residential uses, provided that the following condition is met:
- Backup Space: At least 24 feet of total backup space must be provided. This 24-foot measurement includes the width of the alley itself and is measured from all garage doors and parking spaces that back up onto the alley [§ 18.02.312, Note 6].
Interaction Between Residential Buffers and Alley Rules
The 5-foot residential adjacency setback (Note 7) applies to property lines that are "immediately adjacent" to residential zones. When a property line abuts an alley, it is adjacent to the alley right-of-way rather than the residential property itself. Therefore, if the 24-foot backup space requirement is satisfied, the zero-foot setback allowed by the alley provision (Note 6) takes precedence for that specific property line.
Compatibility and Transition Standards
While the physical setback may be reduced to zero feet at an alley, buildings must still comply with broader urban compatibility standards:
- Height Transitions: Within the MU-MC district, the maximum height is generally 35 feet, but increases to 75 feet within one block of Virginia Street. Projects using the 75-foot standard on blocks adjacent to the one-block area must provide transitions down to 35 feet by the approximate middle of the block [§ 18.02.312, Note 8].
- Compatibility Standards: New buildings constructed within 150 feet of certain residential zones (such as SF, MF-14, or MD-PD) must meet additional compatibility standards for setbacks and stepbacks [§ 18.04.1003(c)(1)].
- Spillover Light: Lighting from nonresidential or mixed-use properties may not create more than 0.50-foot candle of spillover light at an adjacent residentially zoned property line [§ 18.04.1005(d)(3)(f)].