Detroit Considers Updates to Chapter 61 Zoning Code for Residential Density Changes

Detroit is considering updates to its zoning code that would allow triplexes, quads and townhouses in R2 districts and permit accessory dwelling units in R2 through R6 zones. These proposals have not been voted on in 2025 and may be considered in 2026.

Current Zoning Framework

The city's zoning code is set out in Chapter 61 of the Detroit City Code. Originally substantially revised in 2019, the code now spans 936 pages and applies across the city's 139 square miles. It organises development through approximately 30 base districts grouped into Residential (R), Business (B), Industrial (I), Planned Development (PD) and Special Purpose (SD) categories. Major projects require Site Plan Review before a building permit when new construction exceeds 20,000 square feet of gross floor area, when additions increase square footage by 25 percent or more on buildings over 20,000 square feet, or when projects are located in a 100-year floodplain or involve conditional land uses.

Building heights and floor area ratios are set by zone. Low-density zones such as R1 and R2 are typically limited to 35 feet, while higher-density zones such as R6 can reach up to 70 feet. Floor area ratios range from 0.5 in R1 to 1.5 or more in R4.

Implications for Residents and Development Review

Special Land Use Permits are required for conditionally permitted uses that need case-by-case review for neighbourhood compatibility. New construction in Zone A on the Rouge River is prohibited unless it is shown not to harmfully increase water surface elevation during a base flood. These provisions directly shape where and how new housing or additions can proceed in Detroit neighbourhoods.

The proposed changes would expand the range of housing forms allowed in R2 districts and introduce accessory dwelling units in several residential zones. Residents seeking to add units on existing lots or developers planning smaller multi-unit buildings would encounter different review pathways depending on the zone. Projects in flood-prone areas along the Rouge River would continue to face the existing prohibition on new construction in Zone A without demonstration of no harmful flood impact.

Site Plan Review requirements remain in place for larger developments and conditional uses, providing an avenue for review of neighbourhood effects. The code's structure of base districts continues to govern development across the city regardless of any future updates to density rules in residential categories.

Next steps for the proposals will be determined by city processes, with consideration possible in 2026 if advanced.