Council approves zoning changes to support ADUs and small‑scale infill; removal of 'usable open space' aims to ease downtown conversions

Madison’s Common Council voted Feb. 25 to adopt a package of zoning amendments aimed at making modest infill and accessory dwelling units easier to build across the city.

The six‑part ordinance, advanced by the Planning Division and recommended unanimously by Plan Commission, adjusts garage façade rules, allows porches to encroach closer to side property lines in some cases, removes a per‑unit “usable open space” requirement that has blocked conversions downtown and in transit districts, and relaxes limits on ADU size and configuration.

Why it matters: Planners said the changes address frequent, small technical barriers—rules that made perfectly ordinary renovations, conversions or small‑scale infill projects infeasible. The package is intended to enable more “missing middle” housing (duplexes, triplexes, small apartment conversions) without wholesale zoning map changes.

Major provisions adopted: - Garage façade: replaces a strict 2‑foot recessed garage requirement with a more flexible limit: garage doors may project up to 4 feet forward of 50% of the rest of the façade, while keeping a cap that garage doors cannot exceed 50% of that wall. - Porches: allows unenclosed, roofed porches to encroach up to 3 feet closer to a side property line in appropriate situations (corner entries, duplexes, nonconforming side setbacks). - Story/setback uniformity: removes the extra 1‑ft side setback that formerly applied to two‑story buildings in many districts to simplify additions and second‑story conversions. - ADUs: raises footprint limits for detached ADUs to 1,000 sq. ft. (aligning with detached garage limits) and allows attached ADU additions up to 1,000 sq. ft.; removes a numerical bedroom limit for ADUs to better accommodate family households. - Small multi‑unit configuration: allows back‑to‑back and stacked/back‑to‑back plan types for 2‑ and 3‑unit homes to increase design flexibility for conversions. - Usable open space: removes the “usable open space” per‑unit private backyard requirement that constrained infill in downtown/transit overlay areas; other site controls (setbacks, lot coverage, landscaping, stormwater) remain.

Council action and amendments: Plan Commission had recommended a minor height change for ADUs (30 feet), but the council voted to retain the staff‑recommended 25‑foot ADU height limit after an amendment. The council approved the package unanimously after that change.

From the staff point of view: zoning staff said the changes are administrative and target recurring technical barriers—most changes were framed as removing mismatches between homebuilding practice and code language. Plan Commission and staff noted the city’s TOD overlay and downtown regulations already exempt many central sites from the prior usable‑open‑space test, and the change is intended to allow conversion of existing commercial and office buildings to residential where other standards are met.

What to watch: Staff highlighted implementation issues and asked council to consider carefully any later increase to ADU height because taller detached structures could create scale or building‑code complexities. The planning division will publish updated guidance and continue to track ADU uptake; historically Madison issued only a handful of ADU permits annually, and staff said clearer rules should help increase that number.

Ending: The council framed the action as incremental reform to make it easier to add lower‑impact housing within built‑up neighborhoods while retaining core site controls for stormwater, tree protection and setbacks.