Imagine a stadium that has outlived its useful life. The game has changed, fans have moved away, and it’s getting ever more expensive to keep the place in good repair. Fifteen centuries ago in Rome, the only option was to walk away, leaving the Colosseum to shopkeepers, hucksters, and the plunderers who recycled its trove of stone. In 21st-century America, the more common answer is to turn an obsolete structure into a cloud of concrete dust, perhaps in order to put up a new one or just for more acres of wasteful parking. Buildings come down and go up every day, but that ordinary, slow-motion dance of razing and reconstruction comes at an enormous price, because every demolition is an assault on the environment.
Concrete contributes up to 8 percent of the world’s emissions; steel adds another 8 percent. Theoretically, the saving grace of these noxious materials is that they last a long time, but premature demolition dissipates all the energy packed into that mass. New construction sucks up more. Shattering floor slabs, melting down girders, trucking away rubble, excavating new foundations, erecting a whole structure — these are all the urban-scale equivalent of spraying soot around your bedroom. Without a meaningful reduction of that one-sixth of humanity’s greenhouse-gas production, there’s no way we get to our climate targets and keep the temperature within a livable limit.
“Demolishing is a decision of easiness and short term,” the French architect Anne Lacaton has said. “It is a waste of many things — a waste of energy, a waste of material, and a waste of history. Moreover, it has a very negative social impact. For us, it is an act of violence.” Lacaton and her partner Jean-Philippe Vassal won this year’s Pritzker Prize partly on the strength of a self-imposed commandment: Never demolish. That’s a relatively painless position for one architecture firm to take, especially when it’s based in Paris, a city largely preserved in historical amber. But it’s time for American cities to confront their addiction to teardowns.
New York has a long tradition of adaptive reuse, and its once derelict overstock of factories and warehouses has gradually been recycled into restaurants, offices, and condos, rich with memories of coal dust and brawn. But the only law protecting architecture from demolition is the landmarks preservation statute, which confers an inherent right to exist on buildings with aesthetic or historical value. Everything else counts as future rubble. That law proved useless when JP Morgan Chase condemned its headquarters at 270 Park Avenue to death by dismemberment, and there is some irony in the fact that the architect for its much taller replacement, Norman Foster, is widely hailed as an architectural environmentalist because his firm creates ultra-efficient towers. In historical preservation, it’s the surface details that matter, and if those have been chipped away, a building forfeits the cloak of authenticity. But the environment doesn’t care about plaster scrollwork; it’s the bones that store most of the pollutants and do the most damage when they’re pulverized. We need an environmental-preservation statute.
New York need not reach Lacaton and Vassal’s zero-demo goals to do its part in preserving something like our current climate. It need only discourage total destruction, refine its techniques of radical renovation, and embrace efficiency standards at least as high as Europe’s. Swapping out a leaky façade for a tight new skin, installing up-to-date ventilation, plumbing, and elevator systems — these acts of invasive surgery can leave a creaky old tower younger, healthier, and more efficient.
Reuse makes economic as well as environmental sense, even if it’s being adapted to a different use. The developer Frank Sciame had his office run the numbers on a hypothetical 300,000-square-foot midtown office building and concluded that demolishing an existing structure and replacing it with another of roughly the same size would take eighteen months longer than renovating it, and would cost about 50 percent more as well. Rehabs have recently got quicker and cheaper, he says, thanks to new technology that minimizes costly surprises that often crop up once workers start peeling back layers. “When we do highly architectural projects,” he says, “we go to the archives of the Buildings Department and get their old drawings, which are incredibly precise. Then we laser-scan an entire building and overlay them on the drawings.” The merger of two-dimensional blueprints and 3D-modeling gives architects a highly precise map — no need to guess where the pipes are and punch through the walls for confirmation.
The environmental imperative to keep what we have and construct more sparingly conflicts with the social need to address the city’s chronic scarcity of places to live. Yet muscular renovation occurs at precisely the point where climate and housing agendas meet. “There’s a lot of low-hanging fruit,” says Scott Short, CEO of the non-profit affordable housing developer RiseBoro. “We can meet complementary goals. We can deliver buildings that perform better and are more sustainable, give lower-income people a healthier living environment, and do all that with tenants in place.” One way to test that approach would be with a comprehensive overhaul of NYCHA. Public housing is especially vulnerable to being torn down; in many cities, dynamite appeals to officials as a simple — if brutal and generally not very effective — way to flush away poverty, crime, and blight. New York has chosen a different tack: preservation by neglect. NYCHA’s towers still stand, but they are badly in need of new everything.
If the city really wanted to inch towards Vassal and Lacaton’s zero-demo utopia, it could start by renovating some policies and laws. One impediment to widespread renovation for the people who need it most is that the success of an affordable housing program is almost always measured in the number of new homes it can churn out. “That singular focus leaves a lot to be desired in terms of creating thriving, well integrated neighborhoods,” Short says. He ticks off other impediments, too. The rules that govern how low-income tenants are charged for electricity perversely discourage landlords from installing efficient systems. Some high-performance cladding systems with built-in ductwork are popular in Europe but haven’t been able to make much headway in the American market.
The biggest obstacle to non-historic preservation is that the city hasn’t yet come to grips with the concept of embodied carbon: how many resources are consumed and how many pollutants are spewed out in the process of making something. “From a carbon standpoint, you’re better off driving an old gas guzzler than a brand-new Tesla,” says Richard Yancey, CEO of the Building Energy Exchange, a non-profit consulting firm. “And yet embodied carbon hasn’t been part of any serious policy discussion.” In 2019, city council passed Local Law 97, which imposes long-term carbon-reduction goals on large buildings and an escalating series of fines on owners that fail to meet them. But the law deals only with how much energy it takes to keep it going, not how much is trapped in its structure or it would take to replace.
“The law encourages property owners to say, ‘What’s the least I can do?’ That mentality is the greatest impediment to thinking positively about reuse,” says Elizabeth Leber, managing partner at the architecture firm Beyer Blinder Belle. Leber suggests that if developers were incentivized to keep a project’s embodied carbon low and penalized for wasting it, they might make very different decisions. One tactic, for example, would be to leverage the laziness that Leber refers to, imposing much stricter environmental regulations on ground-up construction than a renovation.
There’s one time-honored technique for cajoling developers into stretching themselves: allow them to create more space in exchange. The zoning code determines how bulky a building can be, but it also allows for a sweetener in the form of extra square footage (an FAR bonus in real estate parlance), usually in exchange for a social benefit, like a library or public plaza. The problem is that existing foundations and columns are rarely engineered to support more floors, unless the building is a disused factory built to withstand the weight of machinery. So the extra square footage would have to be transferable to other sites, like air rights, so that it becomes a form of real-estate currency. Instead of tearing down an existing tower to erect another twice as tall, developers could renovate, reap the carbon bonus, then sell it on the open market. The concept is similar to the trade in carbon credits in which one business’ emissions are offset by another’s savings. The difference is that instead of buying and selling the right to pollute, developers would be exchanging the right to create denser, more efficient housing.
That legal tool would be a prod, not a panacea. “It doesn’t have to succeed throughout the city to be useful,” says Frederick Bland, Leber’s predecessor as managing partner at Beyer Blinder Belle. “You can offer it, and some people would take it up and others wouldn’t.” Now that hypothetical obsolete stadium, instead of being a pile of disposable junk, would supply the skeleton for its own replacement, plus the right to erect a shiny new tower somewhere else.