Siskiyou County, CA Building Setbacks & Zoning: Lot Coverage Limits (2026)

Maximum building or lot coverage in unincorporated Siskiyou County is established by zoning district in the dimensional standards table, Section 10-6.5501 (Article 55). The table caps coverage at 40 percent in the Rural Residential (R-R) and Res-1 districts, allows roughly 50 to 75 percent in the Res-2 through commercial districts, permits 75 to 85 percent in the heavier commercial and manufacturing districts (C-H, M-L, M-M, M-H), and limits the Open Space (O) district to 35 percent. Lot coverage works together with the other dimensional standards in the same table, including minimum site area (which ranges from 7,200 square feet up to 40 acres in agricultural and timber-production districts depending on the district and whether sewer or septic service is used), minimum lot width (generally 50 to 100 feet), required yards, and maximum building height. Because the county relies on large minimum parcel sizes in its rural and agricultural districts, total coverage on those parcels is usually well below the percentage cap in practice. Coverage limits restrict the footprint of structures relative to parcel size and are applied during plan review along with setbacks and height. The exact coverage percentage, the way coverage is measured, and any footnoted exceptions depend on the zoning district, so owners should confirm the figure for their specific parcel and proposed structures with the Siskiyou County Planning Division before designing additions or new buildings.