Cambridge, Massachusetts, may seem like an unlikely site for a YIMBY revolution.

The historic Boston suburb is home to both Harvard University and a bevy of affluent homeowners opposed to any new development. The city even features prominently in the book "Neighborhood Defenders," a seminal work about anti-building, not-in-my-backyarders. Despite all that, the city recently passed a series of laws that could pave the way for a cascade of new housing construction.

Cambridge could certainly use the new units. Data from Zillow shows the city's average rent is $3,400 a month — slightly higher than San Francisco's estimated average rent of $3,200. Homelessness in Cambridge has also been on the rise, particularly since the pandemic. In an attempt to ease this pressure, pro-housing groups that fall under the YIMBY umbrella (short for "yes in my backyard") — particularly the local group A Better Cambridge and the statewide organization Abundant Housing Massachusetts — have been trying to get more homes built in Cambridge for years.

In recent years, that work has started to bear fruit: The city enacted a 100% affordable housing overlay in 2020, which allows developers of below-market-rate apartment complexes to build more densely than would be permitted under base zoning. Three years later, Cambridge rezoned its Central Square neighborhood, allowing apartment buildings to rise up to 18 stories high.

But the latest measure is perhaps the most radical, and most promising. A measure passed in February will legalize the production of four-story apartment buildings across the entire city, with some larger lots zoned for up to six stories. Sure, these newly possible buildings aren't quite as dramatic as an 18-story tower, but this latest change is by far Cambridge's most ambitious. Unlike the geographically confined Central Square upzoning, the newest pro-housing ordinance has the potential to remake the entire city. The city's planning staff estimate that the new law may increase Cambridge's housing development capacity over the next 15 years from 350 units to 3,590 — a more than tenfold increase.

The likelihood that some neighborhoods will become denser has provoked the usual opposition from local homeowners. But viewed from another angle, this densification could make the city a more vibrant and beautiful place to live. There's a reason the Cambridge city councilmember Burhan Azeem has called the city's new plan "Paris-style zoning." As it turns out, Paris is a good model for midsize American cities to follow. By allowing more European-style construction, places like Cambridge can both lower housing costs and look good doing it.

Alongside the Eiffel Tower and the Arc de Triomphe, one of Paris' most iconic architectural hallmarks may be its most ubiquitous: the Haussmann-style building. Georges-Eugène Haussmann (better known as Baron Haussmann) was the famed urban planner who, under Emperor Napoleon III, redesigned central Paris in the mid-19th century. Paris became a city of wide boulevards and midrise apartment complexes with distinctive limestone facades — the aforementioned Haussmann buildings. Thanks in no small part to the prevalence of these structures, Paris has achieved a density higher than any other major city in Europe or the United States — although the city of lights still struggles to keep up with demand for housing.

While Haussmann buildings are specific to central Paris, plenty of other European cities have equivalent structures: four- to six-story apartment blocks with no buffer area between the front door and the sidewalk. Unlike the boxy, cheap-looking American five-over-one apartment building that has come to dominate much of our development — and which many people regard as an eyesore — Euro-style apartments generally contribute to the beauty and charm of dense, walkable tourist destinations like Stockholm and Rome. Plus, they're more efficient: thanks to European building codes and zoning rules, European-style apartment buildings can be built for less, on smaller lots, and with more family-friendly apartments in the interior.

"Sure," you might say, "but what's good for Paris, Stockholm, and Rome won't work in an American context." That's a common refrain from skeptics — citing cultural differences, the need for abundant parking, or their own gut instincts — when YIMBYs propose allowing more European-style zoning in the United States. But these assumptions are incorrect for two reasons.

First, upzoning cities like Cambridge is not the same thing as requiring them to build up to Parisian density. If you own a single-family home in Cambridge, and your lot has been upzoned to allow for the construction of a four-story building, you remain at liberty to keep your single-family home. If you want to redevelop the property into a multifamily building, that's great; if you decide to sell your home to a developer who will replace it with an apartment complex, that's great, too. But nobody is compelling you to do either of those things if you like your existing home.

Second, Cambridge — like many other older cities in New England and the mid-Atlantic region — already has a fair number of dense apartment buildings and townhomes. Rather than destroying the culture or character of these cities, building more Parisian-style housing would signal a return to the pre-single-family era. Many of Cambridge's mid-rise apartment buildings were constructed before single-family zoning became ubiquitous in the United States in the early 20th century. And the ones that have survived are now highly coveted as luxury homes and architectural treasures; yet, for decades, it has been effectively illegal to build more of them. As Azeem wrote on X, Cambridge's previous, single-family-focused zoning laws meant that "85%+ of the existing housing" in the city would be illegal to build. In other words, Cambridge's upzoning may actually help to preserve the city's architectural heritage and New England character. At the same time, it is a model for how other cities can upzone in a manner that actually eases housing costs.

While the patchwork nature of American land-use policy can slow progress in important ways, it can also be an engine for experimentation and friendly, productive competition. Pro-housing activists in cities across the country — in places like Minneapolis, Austin, and Sacramento — and far beyond, in the case of Auckland, New Zealand, have inspired each another, shared insights and tactics, and provided a push to see who can push through the most ambitious land-use overhauls. These pushes can even get a little cheeky: YIMBY advocates in Montana sold zoning changes by urging conservative lawmakers to move away from "California-style zoning." While it will take some years to assess the full impact of these revisions, the early data from places like Auckland is very promising.

Some changes make a bigger impact than others. One lesson from the past few years of YIMBY experimentation is that smaller tweaks to local zoning codes may yield negligible results; ambition is vastly superior to cautious incrementalism. Take Minneapolis, one of the recent YIMBY success stories. Citywide, the production of more housing has helped to keep rents and home prices in check, but as the housing researcher Zakary Yudhisthu has found, there's more going on underneath the hood. The parts of Minneapolis that moved from single-family to duplex or triplex zoning have seen little housing growth, while the corridors that allow for denser construction have seen more permit applications. In other words, going just a few steps further is how you get real results.

But to truly unlock housing production at the necessary scale, high-cost cities cannot stop at upzoning. They also need to reshape permitting rules and other onerous building requirements, such as off-street parking mandates. True European-style zoning would allow for mid-rise apartment buildings with no off-street parking and a single central staircase. (Five-over-ones exist in part because most American cities require multiple staircases in any apartment building over a certain height.)

So while other expensive cities should take inspiration from Cambridge, they should also see if they can go even further. There's still plenty of room for another jurisdiction to take the lead in the race to be America's YIMBY-est city. Any takers?

Ned Resnikoff is an urban policy consultant and writer. He is a fellow at the Roosevelt Institute and is currently working on a book about cities with an expected publication date of Fall 2026.

• Jason Kelce is trying to build another home on his Haverford, Pennsylvania estate.
• Neighbors were concerned that construction could lead to a higher chance of flooding in the area.
• Kelce also got permission to add a fence for "unique" security concerns.

Super Bowl champ Jason Kelce recently faced some new opponents: his neighbors.

In 2018, the former NFL offensive lineman started buying neighboring properties in Haverford, Pennsylvania, an upscale suburb of Philadelphia. During a February 20 Haverford Township zoning board meeting, Kelce answered questions about his application to disturb the slopes on his property to build a fourth home and add a fence to his now 10-acre estate.

At least one Haverford resident said in the hearing that they worried changing the inclines on Kelce's property would change the water runoff patterns and lead to flooding of neighboring properties.

Kelce left the meeting with a win: approval from the board. Kelce — who played all 13 seasons of his career with the Philadelphia Eagles and now has a hit podcast with his NFL star brother Travis — and his wife Kylie Kelce have three daughters five and under with another girl on the way.

Other celebrities trying to develop their properties have butted heads with neighbors. Take Ellen DeGeneres and Portia de Rossi, who the Daily Mail was first to report irked some English neighbors after buying a home in the bucolic Cotswolds region. According to minutes from the local government cited by the Independent, parish councilors feared that an addition and a fence the couple were adding to their property would increase the risk of local flooding and possibly endanger historic Roman ruins. The council ultimately found the work was done well and deemed the ruins safe.

While Kelce's plans faced some opponents, he overcame them relatively smoothly.

Kelce and his lawyer Ji Min Jun, who was present at the meeting, could not be reached for additional comment.

The Kelces started buying up property in Haverford in 2018

Delaware County, Pennsylvania, records show Kelce bought his first piece of land in Haverford, a 1-acre property with a four-bedroom home already on it, for $680,000 in 2018. He bought a neighboring property in 2020 for $3.96 million and another one for $1.35 million in 2023.

Haverford, known in part for the small liberal arts college named for it, has a population of about 50,000.

Kelce, his lawyer, and his civil engineer appeared at the February 20 zoning meeting to explain more about what the Kelces wanted to do on the property.

Adding a fence would "deter a little bit of the foot traffic coming in and out of the home," Kelce said at the meeting.

Building a fence and an additional home would, however, "disturb steep slopes" on the property, Jun said.

Neighbor Wendy De La Rosa stepped forward to find out more about how changing the slopes would affect flooding in the neighborhood.

"That whole area does have issues with water runoff," she said. "Especially if there's not going to be any mitigation during the construction period, we want to understand so there's no flooding in the backyard for our kid."

Timothy Davis, a civil engineer for the project, quelled concerns about increased runoff by arguing that the construction should result in better water collection than before.

The board approved the zoning variance for the Kelces to continue working on their fourth home, and board member William Rhodes added the condition that "all stormwater runoff shall be managed by the applicant so as not to adversely affect any neighboring property."

At the meeting, Jun also said that a home on one of the properties has already been demolished, and construction on the new house has begun. The fence was also approved.

• US home prices and rents have soared in part because of a shortage of housing.
• There are four key obstacles to building more housing, according to one industry leader.
• These are the cost of land, a shortage of construction workers, regulations, and NIMBYism.

The US is suffering from a deep shortage of homes, and it's driving sky-high home prices and rents.

The laws of supply and demand explain it: the supply shortage — estimates of which range from 2.8 million homes to more than 7 million homes — coupled with an uptick in demand in recent years has sent prices soaring.

The leader of the top trade association and lobby for the home construction industry thinks there are a few key obstacles to fixing that shortage. Jim Tobin, CEO of the National Association of Home Builders, blamed the high cost of land, a shortage of skilled construction workers, burdensome government regulations, and the anti-development "Not in My Backyard" sentiment for the home shortage.

Cost of land

The cost of land — a significant portion of the cost of a home —has risen significantly in many places in recent years as its availability has plummeted, exacerbated by high demand for housing and restrictive land-use laws that prohibit dense development.

At least 75% of residential neighborhoods in many major US cities like Los Angeles, Seattle, and Chicago are zoned exclusively for detached single-family homes. This means that as demand for housing increases, these communities can't accommodate many additional homes. As demand overwhelms the supply of land, prices rise.

"We just hear more and more that it's harder to find affordable pieces of land to develop for housing," Tobin said.

A worker shortage

A national shortage of construction workers — estimated at around 500,000 workers this year — has also driven up the cost of building new housing and renovating existing homes, Tobin said, noting that skilled workers in residential construction are in particularly short supply.

Fewer construction workers means less — and slower — residential construction and higher wages for workers, which in turn leads to higher home prices. The worker shortage has mounted as policymakers have emphasized college over the trades, and a wave of experienced workers retired during the pandemic, industry experts said.

Lots of regulations

Tobin also pointed out that builders face a significant regulatory burden. Rising demand for housing in recent years has run headlong into a web of local, state, and federal regulations — from restrictive single-family zoning to energy code requirements — that slow down or kill residential construction in communities across the country, he said. When it comes to housing, state and local governments control the majority of regulations that most inflate housing costs by limiting or slowing down construction, but federal regulations also play a role.

"Those delays all add up to more costs and less availability," Tobin said. "We need all options on the table when it comes to increasing housing supply, which means allowing more density in suburbs or cities."

'NIMBY' opposition

Many of these restrictive regulations are bolstered by local opposition to new housing — epitomized by "NIMBY," or "Not in my backyard," sentiment, Tobin said. Many local homeowners oppose new construction for the simple reason that additional housing in their community would depress their home values, he argued.

"One of the challenges we have in localities across the country are people that already have theirs, and they don't want anybody to have theirs," Tobin said. "We have local government officials that won't back more housing development because they're afraid of the backlash from local constituents."

The future of housing

Tobin said the strength of the overall economy and interest rates will also play a major role in determining housing costs over the next few years. He expects mortgage rates to settle into a "new normal" of about 5 to 5.5% by 2026, lower than the current 30-year fixed rate of 6.79% but above the pre-pandemic average.

Looking to next year, Tobin said he expects President-elect Donald Trump to have a mixed impact on housing costs. He's optimistic Trump will roll back some federal regulations and open up some federal land for new housing, but he's concerned about mass deportations potentially shrinking the already scarce supply of workers, and new tariffs inflating the cost of building materials.

Tobin said he plans on working with Trump's transition team, the new administration, and Congress to advocate for tariff policies that don't send building costs surging. "I would certainly welcome an increase in domestic industry when it comes to building materials," Tobin said, "but tariffs only work if that is the outcome."