Trustees discuss shifting density calculations from net buildable acres to simpler methods

Planning staff led a technical discussion July 7 on how the village calculates dwelling units per acre and whether to change from the current ‘‘net buildable acre’’ method. Planner Steve (staff) told trustees the village’s base densities are low — for example, the village’s primary residential zone (R-3) allows roughly 2.5 dwelling units per acre — and that the current net-buildable methodology subtracts parks, ponds, rights-of-way and other deductions in a way that can penalize developers for providing public amenities. He said bonuses in the ordinance (for boulevard length, views, solar orientation and other design features) are often vague or hard to measure. Why it matters: density calculations determine how many units a developer may build, which affects housing supply, neighborhood character, and developers’ financial decisions. Several trustees said the present approach increases uncertainty for developers and can reduce viable housing proposals for small parcels. Discussion highlights: Steve said some nearby communities calculate density on gross lot area, which is easier to compute and more predictable for developers. He gave examples: open ponds counted as a deduction under net-buildable rules reduce allowable units, whereas buried stormwater infrastructure can increase permitted units, creating a visual trade-off. Trustees raised trade-offs for existing homeowners, insurance and rebuilding after storms; Trustee Katzenas and Trustee Malani asked whether the change would disadvantage existing residents and noted potential risks if rules differ from what already exists in neighborhoods. Direction and next steps: trustees asked staff to bring a more detailed comparative analysis, including: gross-versus-net calculations applied to village neighborhoods; visual street-level and aerial examples for each residential zoning district; and a proposal for revising bonuses so the village rewards features it wants and can reliably maintain. Staff also was asked to consider sampling neighborhoods rather than analyzing every parcel immediately.