INSPIRATIONAL
Decarbonizing With Professionals
AMANDINE CADRO
BUILDING CARBON NEUTRALITY ANALYST (NEW AND EXISTING BUILDINGS), STUDIO CARBONE
Under the current energy transition and the fight against climate change, the decarbonization of buildings represents a key priority for industry professionals. It is about more than merely using low-carbon materials; however essential, further strategic levers must be mobilized. To illustrate these complementary methods, architects were given the opportunity to discuss their experiences and concrete solutions via project presentations.
Demountability and end-of-life: A lever to help decarbonize the Mont-Laurier library
In December 2024, the Mont-Laurier library project received a Merit Prize from Canadian Architect for its conceptual innovation in sustainable development. The project received recognition for its innovative “reciprocal structure” concept, offering a “flexibility to adapt the building [and] the potential for complete, planned deconstruction,” according to Stephan Chevalier. The reciprocal structure consists of an “assembly of structural escutcheons that can be prefabricated to support one another in overall equilibrium.” This structural framework facilitates the reversibility of spaces and the transformation of the building without destroying it. Indeed, “the location of the columns can be changed while remaining on the structural axes, making rooms larger or smaller.” In order to “extend the building’s life cycle,” its deconstructibility had to be considered, ensuring that “everything is designed with mechanical assemblies that can easily be undone simply by unscrewing and unbolting. Nothing is welded.”
STEPHAN CHEVALIER
CHEVALIER MORALES
According to Stephan Chevalier, the single most important criterion when choosing the structure’s materiality involved “a desire to anchor the project in its socio-economic context,” before considering its carbon footprint. The structural modules are “made of glue-laminated timber, a resource that stems from the local wood processing economy.” The dimensions of the modular framework (1.22 m x 2.44 m) correspond to “standard wood dimensions within the local industry, which helps preserve resources while minimizing the embodied carbon.”
Stephan Chevalier goes on to say that the system “has the advantage of creating lightweight modules that can be maneuvered by two men without cranes or trucks, which also limits GHG emissions.”
“THE PROJECT’S METHODOLOGY SHOWS A GREAT DEAL OF POTENTIAL FOR ITS REPEATABILITY, BECAUSE IT’S NO LONGER HYPOTHETICAL. THE REPETITION OF SMALL GESTURES, RATHER THAN A SINGLE LARGE ONE, COULD HAVE A REAL IMPACT ON SUSTAINABLE DEVELOPMENT IN THE LONG TERM BY ALLOWING EASILY REPEATABLE METHODS THAT HAVE BEEN SHOWN TO WORK.”
This innovative project remains on budget and fully compliant with the timeline set by the project owners thanks to “subsidies that contributed to its technical development,” namely the Quebec government’s Programme d’innovation en construction bois (wood construction innovation program). This scheduling compliance was made possible in part by “innovating through the existing regulatory framework.” For this particular structure, “the biggest issue involved, among other things, the combustibility of the tie-down systems, which were concealed or protected by the wood, thus complying with the effective regulations.” Stephan Chevalier believes that “the project’s methodology shows a great deal of potential for its repeatability, because it’s no longer hypothetical.” In his view, “the repetition of small gestures, rather than a single large one, could have a real impact on sustainable development in the long term by allowing easily repeatable methods that have been shown to work.” He states a definite preference for projects “that are deconstructable to help decrease embodied carbon,” while highlighting the fact that, for this particular project, “architecture is fully intertwined with structural and mechanical engineering to produce a very coherent whole.”
The Olympic Aquatic Centre in the Greater Paris Metropolis: A holistic approach to decarbonization
The Olympic Aquatic Centre was built to host the water polo, artistic swimming, and diving events at the 2024 Paris Olympic Games. It was inaugurated in the spring of 2024 and received several awards, including the Grand Prix BIM d’Or, along with recognition for its prouesse technique (technical prowess) at the Prix régional de la construction bois, and the Prix Versailles. According to the project’s architects, the challenge involved “considerable environmental ambitions [to] create a building of excellence while demonstrating the ability of France’s building ecosystem to reinvent itself” with a non-extendable deadline. The architects were proud to have met this challenge head-on, as they succeeded in “bringing every stakeholder on board through education.” In their view, the Olympic Games have finally “provided an engine to accelerate projects.”
According to Laure Mériaud, they considered the “decarbonization objective as an immense opportunity to find new solutions, remove our blinders, and question ourselves regarding our design habits and way of doing things.” Cécilia Gross adds that, “decarbonization isn’t simply about using wood and making calculations,” it is also about “analyzing programs and asking questions regarding the actual needs, because everything that’s excluded already represents a gain.”
Various levers were applied under a holistic vision that sought to lessen the carbon used in the project design. First, they had to “question the programming from the very beginning.” They offer the public parking lot as an example. They questioned its actual necessity, stating that “the possibility of pooling resources by using the Stade de France parking lot directly opposite, which remains empty all day and is easily accessible using the footbridge,” as Laure Mériaud points out.
Second, restraint and a resource-based economy guided their design. According to the architects, “thinking about restraint and economy does not mean enduring a sad reality; we simply have to reinvent things.” To reduce energy consumption, the group opted for a tension structure made of wooden beams (catenary beams) composed of homogeneous sections and a 90-metre span. This system “has the advantage of leaning towards a minimal interior volume to heat, thus improving the public experience with greater proximity to the event while remaining lightweight.” This approach can also be found in the swimming pool design. Using divers as an example, “the bottom of the pool is the precise opposite of every height constraint, which increases the complexity involved in its construction, but you still manage to save water by 25%, when compared to a normal pool,” explains Cécilia Gross. Similarly, rather than “having two Olympic pools, the choice was made to create a single modular pool with movable walls” that allow the creation of two pools with dimensions that can be adapted to various configurations and disciplines. According to Cécilia Gross, “this made it possible to reduce the length of the building by 10 metres [and] this one-of-a-kind swimming pool provides a tremendous variety of operational possibilities that cannot be achieved with any conventional system.”
CÉCILIA GROSS
VENHOEVENCS
LAURE MÉRIAUD
ATELIER 2/3/4/
Reversibility also served as an important lever during the project. Indeed, the control room area was intended to accommodate media trucks broadcasting sporting events, so a decision was made to create a cable park that can serve as a day-to-day play area, which can accommodate temporary spreader plates for the control room area during events, rather than creating a 2,500 m2 waterproofed parking lot. Similarly, some of the Olympic grandstands were designed to be dismantled into modules that could make room for sports facilities.
Despite the fact that “decarbonization is about more than using wood,” the material was nonetheless used extensively for the structure “based on the right material in the right place [...] because wood remains a somewhat magical tool for decarbonization,” according to Cécilia Gross. Concrete was used for the basilaire and foundations to ensure robustness and consistency with its usage. The thought process regarding the materials used in the grandstands embraces circular economy principles, with seats made from recycled plastic.
Finally, according to Laure Mériaud, any approach to decarbonization must involve the user’s appropriation and actual use of the building. In her view, “an all-wood building is a failure if it’s terrible and non-functional, and no one wants to go there.” It is therefore important that we “pay attention to interior space, natural light and scale.” Both architects are proud of this “beautiful, impressive and pleasant building that clearly provides light, warmth, and sunshine.”