TREESCRAPERS TO THE RESCUE

By David Jen, American Society of Civil Engineers (ASCE), NOV/DEC 2023

Paris-based firm Vincent Callebaut Architectures designed the Tao Zhu Yin Yuan building in Taipei, Taiwan — a twisting, vertical “forest” that will absorb carbon through its multistory tree plantings. The company looks to apply this same vertical village — or treescraper — concept in New York City, transforming “neighborhoods into forests” and “buildings into inhabited trees producing their own energy and recycling all their waste into resources,” according to press material from Callebaut.

Such designs for biomimetic buildings could help New York City achieve its carbon-neutrality goals over the next three decades.

The design is an amalgamation of technologies: artificial intelligence generative tools, building information models, construction process optimization software, and parametric climate simulation. These tools helped the Callebaut team conceptualize the climate-responsive vertical village.

The design represents a middle ground between “energy-intensive” skyscrapers and “space-consuming” urban sprawl, combining urban agriculture, space efficiency, and renewable energy into people-centric, 3D communities, per press material. “Our biophilic approach is based on bringing the individual and architecture closer to nature and endemic biodiversity,” writes Callebaut.

New York state’s Climate Leadership and Community Protection Act, signed into law in 2019, requires the state to reduce — from 1990 levels — its greenhouse gas emissions 40% by 2030 and 85% by 2050. The law also mandates that by 2030, 70% of the state’s power come from renewable energy sources and from 100% renewable sources by 2040.

Statewide, buildings released the biggest percentage — 32% — of greenhouse gases between 1990 and 2020, according to the New York State Department of Environmental Conservation.

New York City, meanwhile, through its Green New Deal, has committed to carbon neutrality by 2050. And as a C40 city — that is, one that is part of a network of mayors banding together to tackle climate change — it has pledged to enact policies requiring net-zero carbon emissions from new buildings by 2030 and from all buildings by 2050.

To achieve these goals, the Callebaut team devised a four-pronged eco-design strategy. First, it evaluated New York City’s climate data, such as the paths of the sun and of prevailing winds, and their effects on passive cooling and energy efficiency. The next step was to integrate renewable-power generation, such as solar panels and axial wind turbines, into a building’s structure to offset its power consumption.

Living spaces that extend materials’ service life by adapting to evolving intergenerational family needs and shifting private-professional boundaries as well as the inclusion of urban agriculture in the form of greenhouses and orchards built directly into and atop the buildings round out the eco-friendly strategy.

The Environmental Protection Agency has identified green roofs as an ideal way to provide direct and ambient cooling effects in large cities while also improving air quality and absorbing pollutants to mitigate the heat island effect.

A consequence of replacing natural land cover with pavement and buildings — which absorb and retain heat — the resulting urban heat islands increase the need for power-hungry air conditioners and contribute to air pollution and heat-related illnesses. The detrimental effects have added to the disproportionate influence megacities exert on climate change.

Callebaut, however, hopes treescrapers will be a viable path to carbon neutrality for New York City.

This article originally appeared in Civil Engineering Online as “Could ‘Treescrapers’ turn NYC neighborhoods into forests?” It appeared in the November/December 2023 print issue of Civil Engineering as “'Treescrapers' to the Rescue.”