The White House recently announced a new definition around Net Zero building design. The guidelines are the clearest, strongest guide yet for property developers, who now face the possibility of steep fines if they are not in compliance with an increasing number of new carbon emissions laws. The federal government has gotten serious about curbing greenhouse gases in recent years, and a big part of the strategy to do this lies in the building sector, which contributes a large share of all greenhouse gas emissions as buildings get greener; this includes the adoption of greener building practices, such as adaptive reuse projects. But as the push for greener buildings evolves, the next step is to make the entire process net zero, and that means a lot more recycling of existing building materials.
Last month, the White House and the U.S. Department of Energy (DOE) together released a draft of the new national definition for a zero-emissions, or Net Zero, building. By drawing up a new guideline around the standard, the government is aiming to create a common framework that will better help the industry reach its zero emissions goals. The definition encompasses three key criteria that buildings must meet, all of which focus on operations: they must have high levels of energy efficiency, be free of on-site emissions from energy use, and be powered solely by clean energy. The draft definition applies to existing buildings and all new construction projects that are not federally owned buildings. The new guideline is just the first part of the zero-emissions building definition, and more will follow in the future that will focus on emissions other than operational. For instance, the DOE indicated that it would likely address embodied carbon in future updates to the definition.
While not the first priority in many companies’ sustainability efforts, embodied carbon is an area that is beginning to get a lot of attention at the moment. Unlike the carbon footprint created by a building’s operations over time, embodied carbon refers to the carbon footprint created during the building’s construction. Buildings contribute nearly 40 percent of carbon emissions globally every year, and at least one-quarter of these emissions come from embodied carbon, according to the Rocky Mountain Institute. Many developers these days are taking measures during the construction process to cut down on their embodied carbon footprint by doing things like using electric vehicles to ship materials to the site, using ready-mix concrete, choosing finish materials that have a low embodied carbon footprint, and using insulation that has low or no embodied carbon. These and other efforts can make a big difference in cutting down on embodied carbon, but there is one option that can make an overwhelming difference. In adaptive reuse and redevelopment projects, reusing the vast majority of materials to build the new structure can drastically reduce a building’s embodied carbon footprint. “Adaptive reuse is the best way to reduce embodied carbon—period,” said Andrew Rastetter, a structural engineer at the engineering consultant firm Buro Happold.
One of the most high-profile examples of a developer reusing materials is the Quay Quarter Tower in Sydney, Australia. That project was completed in 2022 and was widely celebrated in the design and building industries. It was named the Best Tall Building Worldwide in 2023 by the Council on Tall Buildings and Urban Habitat and the World Building of the Year by the World Architecture Festival. It’s also been touted as the world’s first “upcycled” skyscraper. The tower is a redevelopment of a 1970s office building into a visually striking cantilevering tower located near Sydney’s famed Opera House. Danish design firm 3XN was able to keep two-thirds of the 45-story tower, which was incorporated into the eventual finished product: a new, 50-story tower with double the floor area of the original. By reusing 60 percent of the core structure instead of demolishing the building altogether, the developer was able to not only complete the project several months faster but was thought to have avoided contributing more than 8,000 tons of greenhouse gas emissions, which equates to two years’ worth of operational emissions.
Another large project where developers are reusing existing materials for a new building is JPMorgan Chase’s new HQ building in Manhattan. The banking giant announced it would be demolishing its New York City headquarters in 2018 and replacing it with a tower nearly twice as tall. JPMorgan leaders also announced that the new HQ at 270 Park Avenue would have net zero operational emissions and would be all-electric. But one of the most interesting aspects of the new office tower is that it will be created using 97 percent of the materials from the demolition of the previous building that it will be replacing. During the demolition, JPMorgan said developers recycled, reused, or recycled 97 percent of the materials. Designed by Foster+Partners, the 2.5 million-square-foot office tower topped out in recent months at 1,388 feet tall and was developed by Tishman Speyer. While the bank hasn’t gone into further details about how exactly all the materials from its previous building are being reused or recycled, in a press release announcing the topping out, JPMorgan Chase said the structural steel used in the building is 93 percent recycled and 100 percent recyclable.
Projects like these tend to get a lot of attention, nearly all of which is positive. So it wouldn’t be a stretch to think that more developers will follow this path, seeking to not only meet local, state, federal, and even their own goals around sustainability and Net Zero but to bring their company and property more attention and, potentially, accolades. It’s become trendy, and even though it’s harder to do, high-profile companies are more incentivized to take on the challenge. It would stand to reason that now that big upcycling projects like these have been completed, they can be looked at and studied, and industry professionals can further expand upon what they’ve learned.
The embodied carbon space is one that is rapidly changing as more places around the world look to form regulatory frameworks to help accelerate efforts to reach net zero emissions. In addition to the White House’s recent draft definition of net zero, last month also saw a consortium of construction and building industry groups come together to urge government action in the UK on restricting embodied carbon emissions. The groups are asking party leaders to take action to reduce embodied carbon emissions within two years of taking office. According to the groups, which include the UK Green Building Council, the UK produces 64 million tonnes of embodied carbon emissions every year, more than the country’s aviation and shipping industries combined. As efforts towards tackling embodied carbon emissions grow and the need to repurpose outdated buildings continues, it seems it’s only a matter of time before more high-profile developers choose upcycling over ground-up construction.