Connecticut Zoning Atlas
The Zoning Atlas is a first-in-the-nation interactive map showing how all 2,620 zoning districts and 2 subdivision districts in Connecticut treat housing. With a total of 32,378 pages of regulations read and analyzed, the Zoning Atlas is cumulative and illuminating. This type of project has never been done before on a statewide basis. The Atlas will evolve as regulations change and district boundaries shift. For a draft write-up of findings, CLICK HERE. For an introductory video about methodology and early findings, click here. For corrections, updates, and questions, please contact lead researcher and project coordinator, Sara Bronin.
What Kind of Housing is Allowed in Each Town?
Our data shows that single-family housing is allowed as of right on 91.1% of the land in Connecticut. We have also mapped every district that permits two, three, and four+ family housing. The numbers are 27.5% for two-family, 2.5% for three-family, and 2.1% for four+ family.
Single-family housing is allowed as of right in 99.6% of the land shown as Primarily Residential Zoning, and 69.9% of land zoned as PRZ only allows single-family housing.
Nine towns allow only single-family housing.
Where are Accessory Apartments Allowed?
Our data shows that accessory apartments are allowed in nearly every town in the state: 94% of towns allow accessory apartments in some form or fashion. 85.6% of land allowing residences of any type also allows accessory apartments, and 47.2% of such land allows accessory apartments “as-of-right” (meaning, without costly public hearings or onerous application requirements). 94 towns (56% of all towns) allow accessory apartments as-of-right in at least one zoning district, and 81 (49%) allow such units as-of-right in a majority of zoned land. That said, stringent and inconsistent rules make it difficult for people to build accessory apartments, or even to know how they must build this type of unit. As a result of HB 6107, accessory apartments will be allowed as-of-right on all single-family lots (unless a town opts out!).
What is Allowed Around Train Stations?
Many, but not all, towns have already zoned the area around their train (or CTfastrak stations) stations for at least some multifamily housing. Still, there is significant growth for transit-oriented communities statewide.
Do Towns Allow Walkable, Mixed-Use Neighborhoods?
Some towns already allow neighborhoods with 2-or-more family homes around shops and restaurants, though few allow such housing as of right. As with transit areas, walkable, mixed-use neighborhoods provide an important opportunity for equitable growth.
Where can I find more information about the research itself?
For a draft write-up of dataset contents, methodology, and preliminary findings, download this (lengthy) article about it here. As noted in the article, this will be one of many analyses of this data set to come out in the months and years ahead.
What Does the Zoning Atlas Mean?
Communities around the state have already begun using the Zoning Atlas to see how their town fares. We also encourage you to review stories about it in the New York Times, Courant, the CT Mirror opinion, CT Mirror reporting, WNPR, and the New London Day, among other places, and its reference in the PBSNewsHour segment below.
ZONING ATLAS PROJECT TEAM
Lead Researcher and Project Coordinator: Sara C. Bronin
Interactive Mapping Interface: Ilya Ilyankou of the Connecticut Data Collaborative, through a generous grant from the Community Foundation of Eastern Connecticut
GIS Map Coordination: Cary Chadwick
Data Collection: Giacomo Cabrera, Sarah Cherfan, Constance Chien, Emma Cotnoir, Josephine Cureton, Taylor Dallin, Sophia De Oliveira, Giuliana Duron, Maxine Faisant, Kevin Fitzgerald, Christopher Gelino, Kathleen Gibbons, Erin Hill, Jared Klukas, Andrea Lee, Sunnie Liu, Lucia O’Sullivan, Natalia Perez, Emily Tian, Isaiah Wright
Special Thanks: Municipal planners of 63 towns, who confirmed data accuracy
GIS Map Collection Assistance: David Dickson, Mark Hoover, Quinn Molloy, Emily Wilson