Primary Zoning Districts
A primary district is any of several residence, office residence, commercial, downtown, or industrial districts. All property within the city is included within a primary zoning district. In the zoning code, these districts are described in Chapters 546-550.

Residence Districts. The residence districts are established to preserve and enhance quality of living in residential neighborhoods, to regulate structures and uses which may affect the character or desirability of residential areas, to encourage a variety of dwelling types and locations and a range of population densities consistent with the comprehensive plan, and to ensure adequate light, air, privacy and open space.
R1 Single-family District 
R1A Single-family District
R2 Two-family District
R2B Two-family District
R3 Multiple-family District
R4 Multiple-family District
R5 Multiple-family District
R6 Multiple-family District

Office Residence Districts. The office residence districts are established to provide an environment of mixed residential, office, institutional, and where appropriate, small scale retail sales and service uses designed to serve the immediate surroundings. These office residence districts may serve as small to medium scale mixed use areas within neighborhoods, as higher density transitions between downtown and residential neighborhoods, or as freestanding institutions and employment centers throughout the city. 
OR1 Neighborhood Office Residence District 
OR2 High Density Office Residence District 
OR3 Institutional Office Residence District

Commercial Districts. The commercial districts are established to provide a range of goods and services for city residents, to promote employment opportunities and the adaptive reuse of existing commercial buildings, and to maintain and improve compatibility with surrounding areas. In addition to commercial uses, residential uses, institutional and public uses, parking facilities, limited production and processing and public services and utilities are allowed.
C1 Neighborhood Commercial District
C2 Neighborhood Corridor Commercial District
C3A Community Activity Center District
C3S Community Shopping Center District
C4 General Commercial District

Downtown Districts. The downtown districts are established to provide a range of retail, entertainment, office, employment, residential, institutional and governmental activities of citywide and regional significance. The regulations recognize the unique qualities of downtown as the business and cultural center of the region, as a community of high-density residential choices, and as a place where the combined environment attracts businesses, workers, shoppers, visitors, tourists, and residents.
B4 Downtown Business District
B4S Downtown Service District
B4C Downtown Commercial District
B4N Downtown Neighborhood District

Industrial Districts. The industrial districts are established to provide locations for industrial land uses engaged in production, processing, assembly, manufacturing, packaging, wholesaling, warehousing or distribution of goods and materials. Regulations for the industrial districts are established to promote industrial development and to maintain and improve compatibility with surrounding areas. In addition to industrial uses, limited commercial uses, parking facilities, institutional and public uses and public services and utilities are allowed.
I1 Light Industrial District
I2 Medium Industrial District
I3 General Industrial District