The Zoning by Area dataset represents the location of base zoning districts, density restrictions and parcel specific combining districts (J, P, TS, Z) as specified in Sonoma County Code Zoning Regulations Chapter 26.

The following are explanations of zoning density:

In urban areas, the density limitation is expressed as "number of dwelling units per acre." For example, "R2 B6 10 DU/AC" means the density is 10 units per acre in this zoning district.

In rural areas, the density limitation is expressed as "number of acres per dwelling unit." For example, "RRD 60" means the density allows one dwelling unit for every 60 acres of land.

Some properties also have a MINIMUM lot size requirement. This minimum is indicated by a second number following the density. For example, "AR B6 10/3" means the density is 10 acres per unit and the minimum lot size is 3 acres for purposes of subdivisions. In addition, an example of "RRD CC B6 160/240" means the density is one unit per 160 acres and the minimum lot size is 240 acres for purposes of subdivisions.