The familiar paradox faced by those both involved in material-intensive new development projects and concerned for the environment arose last month at a summit of global design leaders and materials experts in Cairo.
Hosted by the LafargeHolcim Foundation, the nonprofit arm of the Swiss building materials manufacturer, the sixth International LafargeHolcim Forum for Sustainable Construction gathered some 350 architects, material researchers, and sustainable construction experts from more than 50 nations at the American University of Cairo, in Egypt, on April 4-6 to discuss the theme of "rematerializing construction." ARCHITECT attended the triennial forum as part of LafargeHolcim's invited press corps.
Attendees heard keynotes by architecture heavyweights such as Norman Foster, Hon. FAIA, Francis Kéré, Hon. FAIA, and Anne Lacaton, with roundtable discussions moderated by Pritzker Prize winner Alejandro Aravena and Green Building Australia founding CEO Maria Atkinson; visited historic sites and informal settlements to see the good and the bad of Cairo's construction boom; and moved between four concurrent workshops distinguished by subject matter: recyclable and alternative material implementation, material production and energy use patterns, design digitization, and material supply chain improvement.
Discussion
It has become an accepted fact that the built environment and the construction industry are major contributors to greenhouse gas emissions. According to a 2017 report coordinated by the United Nations Environment Program, the built environment accounts for 39 percent of global carbon dioxide emissions. As presenter Maarten Gielen, a designer and manager of Brussels-based material flows collective Rotor, put it: Raw materials are just too cheap, giving builders little incentive to consider alternative or reclaimed materials. And so the cycle continues: Workers extract virgin materials and subject them to energy-intensive processing, and then builders overuse those materials and send many of them to landfill. This reality is abundantly evident in the forum host city of New Cairo—an affluent community about an hour away from its namesake, and the location of the American University—where piles of leftover building materials from new construction and demolition litter the streets.
The five keynote addresses and workshop presentations offered insights into ongoing sustainable construction and design practices and presented alternatives for how the industry can reduce its carbon footprint. German architect Anna Heringer, co-moderator of a workshop on design digitization, outlined her work in Bangladesh collaborating with communities to use local earth to build schools. Mariana Popescu, a doctoral researcher in ETH Zurich’s Block Research Group, presented ultrathin knitted concrete formwork as a material- and time-saving alternative to conventional milled formwork. American artist and MycoWorks founder Phil Ross showcased biodegradable leather made of mycelium, the fibrous root of fungi.
Lacaton, for her part, discussed the benefits of adaptive reuse. "Adding, joining, expanding the existing, superimposing structures, spaces, and uses is always more interesting and promising than starting over from a place [that is] clean and empty," she said. Herzog & de Meuron senior partner Christine Binswanger highlighted designers' responsibility in educating and empowering clients to engage in responsible building practices. "We need to do buildings that people love, that people want to use, that people transform rather than throw away and rebuild," Binswanger said. "We need to do it in a way that will minimize the resources that we need to do so."
In the forum's final keynote, Terreform ONE co-founder Mitchell Joachim, Assoc. AIA, advocated perhaps the most optimistic—if not idealistic—motivation in light of a dire situation: extinction. Discouraged by the monarch butterfly's status as an endangered species in North America, Terreform ONE is proposing the integration of a monarch butterfly sanctuary into the double-skinned façade of an office and retail building in New York City to serve as "a new biome of coexistence for people, plants, and butterflies." The project, currently on the boards, is "intended to serve as an object lesson in enhancing the urban environment with green technologies."
Debate
For all the innovative ideas presented at the conference, the reality that its sponsor, LafargeHolcim, is one of the largest providers of cement and concrete—which account for some 5 percent of the total manmade greenhouse gas emissions worldwide—was not lost on many of those in attendance. The LafargeHolcim Foundation is dedicated to raising awareness about sustainable construction, but its parent company generated approximately $26 billion in sales of these energy-intensive commodities in 2017.
In a 30-minute keynote presentation on the forum's opening day, Egypt's deputy housing minister Khaled Abbas lauded Lafarge's work on what will be the tallest glass tower on the continent, currently being erected in the new administrative capital under construction about 28 miles outside Cairo. It is one of 20 cities that Egypt is building to collectively house a population of 30 million. (With 20 million inhabitants, Cairo is considered one of the most congested cities in the world.) Abbas outlined plans for some of these new metropolises, each of which was designed in a different and somewhat disparate architectural style—for example, a Mediterranean metropolis or a Dubai-like urban downtown—and represented a clear departure from a context-driven approach favored by many in attendance.
“I will do this with a lot of respect, but also trying to be as clear and honest as possible,” Aravena said in a discussion following Abbas' keynote, with Foster, Binswanger, and Atkinson. “I wonder: Is there room to change the direction and change the path of what was presented by the deputy minister in terms of the built environment?”
His question was met with a roar of applause and would loom large for participants for the remainder of the forum. “What we saw in this presentation is not looking nostalgically at architectural languages of the past,” Aravena continued. “I wonder if it is clear that the glass tower is going to be the tallest greenhouse effect generator in Africa.”
According to the government, the new developments aim to relieve congestion across the country and provide housing for those of all income levels. However, some local conference attendees detail the nation’s history of constructing new neighborhoods that are priced only for the wealthy elite. The city of New Cairo, for example, was planned and constructed 20 years ago but many of the residential villas that define the community’s landscape are empty, have already been subdivided into apartments as more affordable living options, or are simply unfinished. It remains to be seen if the new cities will fall victim to the same outcome.
Conclusions
In the closing workshop presentations, Heringer—one of the few voices explicitly critical of LafargeHolcim—called on the company to reconsider its material pricing, presumably to limit waste and to encourage builders and developers to seek alternatives in new construction. In contrast, German architect Werner Sobek praised Egypt’s efforts to develop at such a rapid speed to meet the needs of its people—citing his own nation’s inability to build its goal of 400,000 residential units in the last year. Other workshop presenters called for more pilot programs to advance research and increase open-access databases for improved education across borders.
The solutions aren’t always easy, but the forum made it clear that cutting emissions even as we house burgeoning populations around the globe is a necessity. Our fate may very well depend on it.
