Disposition Summary

Approve amendments to the City of Knoxville Zoning Code, Articles 4.6, 9.1, 10.1, and 14.6, which provide revisions to the Middle Housing standards and related zoning code elements, because they create additional clarity in the zoning standards and will generate better consistency with the surrounding neighborhoods.

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Staff Recommendation

Approve amendments to the City of Knoxville Zoning Code, Articles 4.6, 9.1, 10.1, and 14.6, which provide revisions to the Middle Housing standards and related zoning code elements, because they create additional clarity in the zoning standards and will generate better consistency with the surrounding neighborhoods.

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The proposed amendments are a result of extensive collaboration among Planning, City Plans Review & Inspections, and City Law Department staff, and based on analysis of eighteen months' worth of potential projects and applications, alongside input from the public and industry stakeholders. The Middle Housing (MH) standards were approved by the Planning Commission in December 2023 and adopted by the Knoxville City Council in February 2024. During the legislative process, Planning stated the intent to review the standards within a year of adoption, analyze the related projects, and identify elements requiring revision or update. To date, Planning staff have reviewed 63 applications and held over 60 formal pre-application meetings, in consultation with City Zoning, Engineering, and Law staff. Planning staff have also analyzed the first year's projects in a comprehensive report. The 2024-2025 Middle Housing Annual Report provides a detailed review of all MH applications received in the first year of the code's adoption, along with a list of "opportunities to improve." The associated zoning code amendments are informed by the applications received, and relate to the issues and recommendations identified in the report.

Additional revisions proposed since the July meeting are highlighted in red in the memo, and in blue in the proposed code amendment text. The revisions are informed by additional evaluation of public comment, input from industry stakeholders, and staff analysis. Planning staff completed extensive data analysis, including the evaluation of existing lot widths within the TDR land use area and average building widths in approved applications.

The aim of the proposed amendments is to allow for the effective use of existing lots, while also ensuring the scale and form of housing built under the Middle Housing standards compliments existing building form, placement, and setback patterns within Knoxville's neighborhoods.

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Article 4.6, Middle Housing Standards

• Adds a statement that Article 4.6 may not be combined with standards from the base zone for principal uses. New principal use projects are subject to Article 4.6 or the base zoning requirements but may not mix and match standards.

This statement adds clarity to the MH standards, which are meant to be used in place of the base district zoning regulations. Mixing standards from the base zoning and the optional MH standards leads to higher intensity development than intended by either the base zone or MH. Selecting standards item-by-item to suit a project can result in the maximum intensity allowed by both standards, and create conflicts in zoning review, permitting, and enforcement.

Article 4.6.A, Middle Housing Types

• Specifies that one unit of a duplex may face the street and one may face either the rear or corner side yard.

• Clarifies that certain triplex types may be up to 2.5-stories tall instead of only 2.5-stories tall.

• Clarifies that triplex types do not also include townhouse-type buildings.

• Clarifies that all townhouse units may feature entries oriented towards the street.

• Clarifies the specific number of units permitted under townhouse (small) and townhouse (large). The permitted number of units is unchanged, but the number is stated more clearly.

• Clarifies that multiplex types do not also include townhouse-type buildings.

The revisions to the Middle Housing types, based on staff review of multiple applications, address minor ambiguities within the types which have created confusion in applications and enforcement. The descriptions for triplexes and multiplexes created ambiguity that allowed applicants to interpret both types as townhouses, featuring units with shared side walls, designed perpendicular to the street on narrow lots. Side-facing townhouses deliver taller massings which loom over adjacent neighbors, create little activation at street level, and are not typically house-scale within the broader block. Permitting side-facing townhouses would allow developments that maximize the potential footprint on a lot and have a different relationship to the streetscape than the existing block, facing side neighbors instead of the sidewalk. Revisions to the Middle Housing Types' descriptions will provide additional clarity within the distinct types and generate new buildings that are more consistent with the block and neighborhood.

Article 4.6.B.2, Middle Housing Uses, Location Criteria

• Adds a statement that Middle Housing types are not permitted on flag lots or lots accessed by access easements.

The new building's relationship to the blockface and streetscape is inherent to the concept of Middle Housing. Allowing for new multi-unit structures without direct frontage to the street, located behind the existing blockface, creates a new development pattern that may not be consistent with the neighborhood context. Development of flag lots and lots accessed by easements is still permitted via the base zoning.

Article 4.6.C, Middle Housing Dimensional Standards

• Changes the ' marker to "feet" for consistency with other lines.

• Specifies that porches and stoops may supersede the permitted encroachment standards in Table 10-1, allowing porches or stoops to encroach into the minimum allowed front setback up to eight feet, but must be set at least five feet from the front lot line.

This addresses an incompatibility between Article 4.6.C and Table 10-1 in Article 10.4. As written, the MH standards require the front setback to be the average of the blockface, plus or minus five feet, no less than ten feet. The encroachments section allows for a five-foot maximum encroachment of an unenclosed front porch into the front setback. These conflicting standards have led to recurring issues where many applicants wanted an eight-foot-deep front porch which was not allowed under Table 10-1. The proposed change allows for front porches on Middle Housing types to be compatible with the scale of other front porches in the surrounding neighborhoods, but do not differ from the existing front setback pattern of the block.

Article 4.6.C, Table 4-4, Middle Housing Dimensional Standards

• Reduces the minimum lot widths for duplex (side-by-side), triplex, and fourplex to 40-ft wide for lots with an alley, and 45-ft wide for lots without an alley.

• Reduces the minimum lot width for a duplex (stacked) to 35-ft wide for lots with an alley, and 40-ft wide for lots without an alley.

Planning has reviewed many applications for Middle Housing types which fit on 40 ft and 45 ft wide lots, meet the other dimensional and design standards, and remain compatible with the scale and context of the neighborhood. Reducing the minimum lot widths for the three least intense housing types also offsets challenges proposed by removing the potential for administrative variations for lot width. Finally, as many non-conforming lots of record within the TDR land use area are 40 ft and 45 ft wide, these lots can still developed using the MH standards in relation to the proposed amendments to Article 17.3 (7-E-25-OA).

Article 4.6.E., Middle Housing Design Standards

• Revises the requirement for vertical articulation in front or side elevations longer than 50 feet.

This statement clarifies the design standard, which is intended to require articulation on long side elevations, avoiding flat swaths of siding with no additional detail beyond the occasional window. The intent is to generate new buildings with varied massing, similar to original buildings in the surrounding neighborhoods, and to avoid the default boxlike forms which may be easiest to design and build. The revised proposal aims to be less prescriptive in the size and design of the articulation, allowing the "vertical break or offset" to be proportionate to the building elevation.

Article 4.6.G, Administrative Variations

• Removes lot width as an allowable administrative variation.

Allowing an administrative variation for lot width with only the criteria provided in 4.6.G.1.a.i created the possibility for subjective and inconsistent decision-making by staff. There was insufficient criteria for allowing or dis-allowing a variation. Moreover, the 20% allowance could be a larger number when applied to larger housing types like multiplexes. In response to removing this variation, the minimum lot widths have been reduced for the four least intensive housing types in Table 4-4.

Article 4.6.G, Administrative Variations

• Clarifies where specifically in Article 4.6.E administrative variations may be granted for design standards, recognizing designs which are compatible in style with the context.

This statement specifies administrative variations may be granted to Article 4.6.E.4.c, which requires at least three of the listed design elements, and allows for the approval of other design elements not listed, provided the design is compatible with the context.

Article 4.6.G, Administrative Variations

• Removes front setbacks as an allowable administrative variation.

The administrative variation allowing minimum front setbacks to be decreased up to 50%, provided they are consistent with the blockface, was redundant and impossible to achieve. Front setbacks are already required to be the average of the blockface, plus or minus five feet, so they would already be consistent with the blockface and a 50% reduction would contradict that.

Article 4.6.G, Appeals

• Delegates appeals to the Design Review Board.

The Planning Commission typically hears rezoning and subdivision concept plan applications that are broad in scope, instead of detail-oriented design review cases. The Design Review Board (DRB) already hears applications for the Infill Housing overlay and the downtown districts, which involve a high level of detail and assess design related to neighborhood context. The DRB is a better fit for hearing appeals to staff decisions.

Article 9.1, General Use Regulations

• Clarifies that multiple principal uses on one lot are not permitted using the Middle Housing Standards (Article 4.6).

Article 10.1.A, General Development Requirements

• Clarifies that multiple principal buildings on one lot are not permitted using the Middle Housing Standards (Article 4.6).

The MH standards were not written with the intent of accommodating multiple primary structures or uses on one lot. In combination with Article 4.6, Article 9.1 and Article 10.1.A allowed for a loophole where multiple primary MH types or structures could be built on properties zoned RN-3 or RN-4. This has led to multiple rezoning requests to RN-4 for lots in neighborhoods predominantly zoned RN-1 and RN-2, with the intent to construct multiple multi-unit structures on one lot. Stacking multiple multi-unit buildings on one lot without additional standards guiding building placement, size, and orientation is not aligned with the intent of the MH standards and does not create "incremental density in housing forms that are compatible with the surrounding neighborhood character."

Article 14.6, Design Review Board Powers

• Allows the Design Review Board (DRB) to hear appeals of staff decisions under Article 4.6.

Adds the MH appeal process as a specific power of the DRB.