fb-pixelNew Hampshire Zoning Atlas unveiled to help policymakers address housing issues - The Boston Globe Skip to main content

New Hampshire Zoning Atlas unveiled to help policymakers address housing issues

Researchers spent more than a year poring over 23,000 pages of ordinances to illuminate the state’s patchwork of local land use rules, which affect what kind of housing can be built and where

Researchers affiliated with Saint Anselm College who spent well over a year reviewing and compiling local land use regulations unveiled their work product, the New Hampshire Zoning Atlas, on Tuesday, May 9, 2023, which displays zoning regulations in interactive color-coded maps. View the maps at NHZoningAtlas.org.Handout

The local rules that govern what can be built where in New Hampshire vary widely from one community to the next, leading to an inconsistent patchwork of land use regulations chock full of jargon.

Such a complex and decentralized system makes it difficult for local and state policymakers to do their work, so a team of researchers affiliated with Saint Anselm College set out to bring clarity. After more than a year of tedious labor, they unveiled their end product, the New Hampshire Zoning Atlas, on Tuesday.

The atlas, which is published online, displays New Hampshire’s local zoning regulations in interactive color-coded maps. The plan is to update the catalog on an annual basis to help policymakers and the public see local rules in their regional and statewide context, according to Max Latona, the project’s director.


Latona, executive director of the college’s Center for Ethics in Society, said it’s easy for local leaders to focus on their own cities and towns without recognizing the aggregate impact local land use rules have on the affordability and supply of housing across New Hampshire.

“For me, the number one hope is that community leaders will take a look at their communities and how their communities are zoning, particularly in the context of other communities around them,” Latona said.

The atlas itself is purely descriptive. It doesn’t recommend any policy changes. Still, some partners on the project pointed to the findings as evidence that policies need to be adjusted to open up more housing stock.

Ben Frost, deputy executive director and chief legal officer for New Hampshire Housing, said the nature of zoning has evolved over time. What began a century ago as an effort to protect public health, safety, and welfare shifted in response to building booms of the 1970s and 1980s, with many communities adopting restrictive zoning policies that allow single-family homes on large lots and prohibit just about everything else.


Now there’s a housing crunch. The state currently needs more than 23,000 additional units to stabilize its supply, and population growth estimates indicate much more housing will be needed in the years ahead, according to New Hampshire Housing’s latest needs assessment. So it’s clear that more units need to be built, Frost said.

“This doesn’t mean that any community needs to be flooded with housing,” he added, “but we do need to see modest increases in housing production throughout the state.”

But local zoning barriers can impede housing development, sometimes in ways that defy logic, Frost said.

For example, Frost pointed to the state’s 2008 workforce housing law, which requires municipalities to offer a “reasonable and realistic opportunity” to develop workforce housing. Some communities responded by doing the bare minimum, so there are now areas where it’s easier to build a five-unit residential building than it is to build a duplex, he said.

That appears to be the case in Sharon, a tiny town in southern Hillsborough County, where developers can build housing either for one family or for five or more families. Housing for two, three, or four families is prohibited in Sharon, according to the zoning atlas.

Minimum lot sizes also contribute to housing affordability challenges, the researchers said. Most communities require an acre or more of land and at least 200 feet of frontage to build a single-family home, so it’s tough to find space for small or starter homes, and large lot requirements for multifamily housing make those projects more expensive as well, the researchers said.


Small-lot single-family housing is “highly restricted in most of the state,” said Jason Sorens, senior research faculty at the American Institute for Economic Research, a free-market think tank.

Sorens, who worked previously for the college’s Center for Ethics in Society, said about 10 students contributed to the research, poring over more than 23,000 pages of local ordinances over the past 16 months to produce the atlas.

Outside of work, Sorens campaigned for his local planning board in Amherst earlier this year. His candidacy faced public skepticism based on his status as the founder of the Free State Project, but he said that movement is irrelevant to his expertise as a land use researcher.

The atlas includes information about manufactured housing and accessory dwelling units. State law requires communities to allow ADUs, commonly called in-law suites, but the approval process and local requirements, such as the need for additional parking spaces, limits ADU development, the researchers said.

Latona said the New Hampshire Zoning Atlas, which cost about $100,000 to produce, is affiliated with a national effort that has partner projects underway in more than 20 states, including all six New England states. New Hampshire is the third state to complete its project. The first two were Connecticut and Montana, he said.

Steven Porter can be reached at steven.porter@globe.com. Follow him @reporterporter.