housing diversity: overview

How can zoning be used to support a diversity of housing types?


Most communities in the U.S. have some form of zoning policy (often expressed through a zoning ordinance or code) that dictates the types of land uses that are allowed in different parts (districts) of town. Originally adopted to ensure the separation of incompatible uses - to make sure residential areas were not built next to heavy manufacturing, for example - zoning is now used more broadly to shape neighborhoods and regulate an array of issues related to property use, such as density, parking requirements and building height. Zoning policies also specify the types of structures that are allowed within each district "as of right" - without the need for a special review process - and often restrict development in residential districts to detached single-family homes. Zoning policies that are written to allow a diverse range of housing types, including multifamily homes, manufactured homes and accessory dwelling units, make it possible to deliver housing that meets a broader range of needs and price levels.


What problems are solved by zoning policies that allow a diversity of housing types?


Many communities have zoning policies that make it difficult or impossible to develop multifamily or manufactured homes and other types of housing that tend to be more affordable to working families. Even when efforts to obtain a variance or conditional use permit to proceed with development that is not allowed "as of right" are successful, the process can lengthen the development schedule significantly, increasing unpredictability and total development costs. By introducing reasonable standards for manufactured homes and reducing regulatory constraints on the development of all of these housing types within appropriate areas, communities can help make sure that new homes are affordable to households at a range of income levels.

Restrictive zoning policies also limit the ability to accommodate the needs and preferences of a community's changing demographics.  Married couples with children now represent less than one-quarter of U.S. households.  Older adults, couples without children and people living alone have different housing and services needs. Through a comprehensive revision of zoning policies, communities can expand and diversify the local supply of homes to meet the needs of a changing population.  (Learn more about revisiting zoning policies to meet the housing needs of older adults.)


Where are these policies most applicable?

Most large cities and many smaller communities have adopted zoning policies (Houston, TX is a notable exception). All jurisdictions with a zoning code may be able to broaden the diversity of allowable housing types by revisiting their policies, and giving special consideration to ameliorating restrictions and potential obstacles to the development of a diversity of housing types.  
Solutions in Action
Carthage Mills
Photo courtesy of Potterhill Homes.

The Mills of Carthage in Cincinnati, Ohio demonstrates that factory-built homes can be effectively used as part of a community revitalization strategy in urban and suburban areas. The development is composed of 50 manufactured and modular homes, and sales prices started at $137,300 in 2002 when the units were first made available for purchase.

Visit the Gallery to learn more about the Mills of Carthage and other developments made possible through policies that support housing diversity.

Similarly, jurisdictions whose zoning appeals boards are inundated with requests for variances and conditional use permits may wish to consider reassessing current regulations to improve responsiveness to shifting demographics and reduce development times and costs.  These communities may also want to consider rezoning some industrial or manufacturing areas as residential to better accommodate the demand for housing.


Museum PlaceLearn more about zoning that allows a diversity of housing types




Mandela GatewayGo back to learn about other policies that help Reduce Red Tape



The Center for Housing Policy gratefully acknowledges the input and feedback provided for this policy section by the following reviewers: Thayer Long, Manufactured Housing Institute; Doug Moritz, DOMO Consulting. Please note, however, that the views and opinions expressed on HousingPolicy.org are those of the Center for Housing Policy alone.