The Birmingham City Commission on Aug. 11 approved ordinance amendments revising open‑space standards for single‑family zoning districts and refining the city’s definition of “impervious surface.” The Planning Board had studied the issues over multiple sessions and recommended the changes to help align zoning with modern stormwater and landscape practices.

What changed: The amendments remove a blanket listing of “stone” from the impervious‑surface definition and add clarifying language. In single‑family districts (R‑1, R‑1A, R‑2, R‑3), the ordinance now specifies that the required 40% minimum open space must consist of at least 75% vegetated open space; paving, permeable pavers and similar hardscape will not count toward the vegetated portion. The drafting draws on Oakland County stormwater standards and aims to keep front yards largely vegetated while allowing certain engineered, pervious solutions when maintained.

Why staff and planners recommended the change: Planning and engineering staff told the Planning Board that the previous, literal inclusion of “stone” could unintentionally classify engineered infiltration trenches (which commonly include stone layers) as impervious and would penalize accepted stormwater practices. The amended language also narrows the instances where permeable pavers or turf‑backed systems are treated as vegetated open space, recognizing maintenance and long‑term clogging issues.

Vote: The commission voted to adopt the ordinance changes on Aug. 11 after the Planning Board presented its recommendation. The roll call vote was unanimous in favor.

Ending: The City will publish the ordinance amendments and begin implementing the clarified standards for future permitting and plan review. Staff said the Board of Zoning Appeals remains available for applicants who believe a particular treatment requires special engineering review or an exception.