San Bernardino, CA Building Setbacks & Zoning: Lot Coverage Limits (2026)

San Bernardino Development Code regulates both building lot coverage and impervious surface coverage on parcels. Single-family Residential Suburban (RS) and Residential Urban (RU) zones typically allow 40 to 50 percent building coverage. Residential Medium and High density zones permit up to 55 to 60 percent coverage, and commercial and mixed-use zones allow 60 percent or higher depending on FAR and setback compliance. Lot coverage is calculated as the sum of all structures and roof overhangs over 30 inches divided by total parcel area. Driveways, patios, walkways, and pool decks under 30 inches in height are typically excluded from building coverage but count toward impervious surface limits. Stormwater management under the San Bernardino County MS4 Permit and California State Water Board construction general permit requires on-site infiltration or bioretention for projects disturbing 1 acre or more, and smaller projects over 2,500 sq ft of new or replaced impervious surface require Low Impact Development (LID) features. Hillside overlay zones in the north end foothills reduce allowable building footprint by slope category, preserving natural drainage and vegetation. Front yard landscaping is typically required to include at least 50 percent landscaped area exclusive of the driveway. Accessory structures and ADUs count toward coverage, though state ADU law preempts certain coverage restrictions for ADUs up to 800 sq ft (Gov Code 65852.2). Swimming pools and detached garages contribute to calculations.