This New York City Building's Façade Actually Cleans the Air
In the past year alone, creative strategies have proved that projects can—and should—set their eco-friendly sites beyond a simple rooftop solar panel. From 3-D-printing an entire home to prevent waste material to investing in Passive House structures that limit energy usage, architects, developers, and scientists are strengthening an arsenal of tools that we need perhaps now more than ever.
570 Broome , a 25-story luxury condo tower in Manhattan's Hudson Square, slated to be completed at the end of 2018, boasts a subtle yet substantial environmentally conscious feature—its façade actually cleans the air. What's more, the structure is situated next to New York's traffic-ridden Holland Tunnel, making its presence even more welcome in the area. The building is clad in 2,000 square meters of Neolith paneling—a material comprised of raw minerals that have undergone high heat and pressure to mimic the appearance of natural stone—that is coated with a titanium dioxide nanoparticle-based treatment called Pureti.

A rendering of the façade at 570 Broome.
Travis Conrad, an architectural consultant for Neolith, explains that the Pureti-treated panels are self-cleaning and actively altering the chemical makeup of the surrounding air. "First, it is hydroscopic, meaning it allows water to not leave streaks—it sheets the water and dirt away from the building," he says. "And it's photocatalytic…it reacts with the sunlight and moisture in the air and breaks down volatile compounds in the air much like how a tree breaks down greenhouse gases."
Thanks to Pureti's decontamination and self-cleaning properties, the process is a trickle-down effect. When UVA beams hit the panels, oxygen and water vapor in the atmosphere are converted into super oxide and hydroxyl; super oxide then converts harmful nitrous oxide in the atmosphere into benign nitrates while hydroxyl converts volatile organic compounds and soil into minerals, gas, and water. In short, what begins in the atmosphere as soil, chemicals, and nitrous oxide becomes little more than minerals and H 2 O.
Architect Tahir Demircioglu—principal of the firm Builtd—who designed the project, explained that, initially, the team chose the building's exterior material without knowledge of its environmental impact. "The initial selection of the Neolith panels was for their lightness and aesthetic reasons, but once we found out it came with this element, we were like, of course," he says. 570 Broome's exterior also limits the amount of chemicals needed to clean and maintain its façade. "Instead of using chemicals and power-washing the façade, because the material is hydrophilic it cleans itself," Demircioglu adds.
Though the chemicals that make up Pureti were discovered some 40 years ago, it wasn't until it was combined with Neolith that it was utilized on the scale seen on major residential towers like 570 Broome. "It's about getting it down in nanoparticles and size," Conrad explains. "The intent is to get as much of the mineral as flat on the surface as possible because [Pureti] has to interact with the moisture in the air and the sunlight." Thus, spraying the solution on a large, thin sheet of Neolith—where all particles can live at the surface—is ideal. "The material is a win-win situation for everybody," Demircioglu adds. "It has an environmental impact, it helps the owners and developers lower the maintenance costs, and it gives a peace of mind to the tenants."