What is the definition of density?

Residential density is the land area required per residential dwelling unit. In low density residential and agricultural land uses, this is generally a number of acres per dwelling unit. In developed areas with urban services, it is generally dwelling units per acre.

Density helps determine subdivision potential. For example, if land use for a parcel is Rural Residential with a 5 acre density, a 20 acre parcel could be split into 4 parcels, while a 19 acre parcel could only be split into 3 parcels.

In developed areas, residential density also determines how many units can be in a multi-unit building. For example, a 1 acre Medium Density residential parcel with a density of 8 units per acre could be developed with an 8-unit apartment or 8 small individual units.

Residential densities are based on the availability of public services and infrastructure, land use compatibility, environmental suitability, projected population and development, and neighborhood character.

Please see the Zoning Search and Zoning Codes page for additional density examples, information about zoning codes, and how to look up the zoning designation for a parcel located within unincorporated Sonoma County.