Springfield, OR Building Setbacks & Zoning: Lot Coverage Limits (2026)

Springfield Development Code section 3.2.225 sets three separate ceilings, and every lot in the R-1, R-2 and R-3 districts falls under one of them. First, on any lot with an average slope greater than 15 percent, or sitting above 670 feet in elevation as calculated under section 3.3.500, impervious surface, meaning pavement, roofs, and other hard surfaces, cannot exceed 35 percent of the lot, a tighter cap meant to limit stormwater runoff and erosion on Springfield's hillside terrain. Second, on a smaller lot under 4,500 square feet that is not in the hillside category, impervious surface can reach 60 percent.

Third, on a standard lot of 4,500 square feet or larger, the limit switches from an impervious-surface measure to a lot-coverage measure, building footprint plus other coverage, capped at 45 percent. The section makes clear these are maximums only, and that a separate stormwater-treatment-facility requirement under section 4.3.110 or another development standard can force an even smaller impervious footprint than the table allows. Cottage Cluster Housing is expressly carved out of the whole section, so a cottage cluster project is not held to any of the three percentages here, though it must still meet its own standards under section 3.2.260.

Anyone building an addition, driveway, patio, or accessory structure that would push a lot's impervious surface or building footprint past its applicable ceiling needs to recalculate before pulling a building permit, since the limits apply to all development, not just new construction on a vacant lot.