Cambridge Zones for Multifamily Housing Citywide

On February 10, 2025, The Cambridge City Council voted to adopt two zoning petitions to allow multifamily housing citywide. For the first time in Cambridge zoning history, all residential neighborhoods have the same zoning rules and all districts (except open space) are zoned to allow multifamily housing. The goals of the zoning changes are to:

• Increase housing production by allowing the development of multifamily housing in all residential neighborhoods in Cambridge.
• Promote more income-restricted affordable housing through the city’s inclusionary housing program.
• Remove some requirements that make it more difficult to build multifamily housing, such as minimum lot sizes, limits of the number of housing units, and on the amount of floor area.
• Continue to encourage the creation of permanently affordable housing through the inclusionary housing requirements and Affordable Housing Overlay (AHO).

The new zoning code makes the following important and noticeable changes:

• Establishes new base zoning for most neighborhoods. Almost all residential neighborhoods are now zoned as “Residence C-1” (Res. C-1).
• Establishes a new height limit for Res. C-1 that allows residential developments up to four stories (45 feet).
• Allows residential buildings up to six stories (74 feet) if:
  • 20% of the residential units are inclusionary (income-restricted affordable housing) and
  • the lot size is at least 5,000 square feet.

Despite this substantial reform of the Cambridge Zoning Ordinance, many zoning standards remain unchanged, including:

• Climate Resilience requirements.
• Inclusionary Housing requirements.
• Green Building requirements.

There are also standards for development that are outside of zoning and are unchanged, including:

• Building codes (including fire safety, sanitary codes, energy codes).
• Historical Commission review (demolition permits, development in historic districts).
• Tree Protection Ordinance.

Additional information, including details about more technical or procedural changes, is available in the new Zoning Ordinance text here. You can also visit cambridgema.gov/multifamilyzoning for information about the original zoning petitions and about the public process that preceded the City Council vote.

Below, you will find answers to the questions people ask most often about these zoning changes.

FAQs: Citywide Zoning for Multifamily Housing

When do the changes to the Zoning Ordinance go into effect?

The changes are effective immediately. However, it will take a few weeks to update the official Zoning Code. In the meantime, the official text is available here and the new Zoning Maps are available here.

My zoning district used to be called Residence A or B. What is my zoning district now?

All Residence A-1, A-2, B, and C are now Residence C-1 districts.

What type of housing can be built in Residence C-1 districts?

All types of housing can be built in Residence C-1, including single-family homes and multifamily housing up to four stories tall. On lots over 5,000 square feet, residential buildings can be built up to six stories if 20% of the residential floor area is used for permanently affordable housing (also called inclusionary housing).

Does the Zoning Code ban new or existing single-family homes?

No. Existing single-family homes can remain, and new ones can be built. Before City Council voted to change the Zoning Ordinance, some parts of the city had zoning that allowed only single- or two-family housing. The new zoning now allows all types of housing, including multifamily housing, in all districts (except Open Space).

I live on a street with mostly single-family homes and the house next door is for sale. If a developer buys it, what can they build on the lot?

The developer can build any type of housing on the lot. They may build a single-family house or a multifamily building up to four stories tall. If the lot is at least 5,000 square feet, they may build a multifamily building up to six stories tall if at least 20% of the residential floor area is used for permanently affordable housing.

How will these changes affect the availability of affordable housing in Cambridge?

Allowing multifamily housing citywide is intended to lead to more housing being built. The goal is to alleviate overall demand for housing, which makes market-rate housing more affordable, and to create more permanently affordable units through the Inclusionary Housing zoning requirements. Another goal is to have multifamily housing spread more equitably throughout the city.

For more information please visit cambridgema.gov/multifamilyzoning.