New design techniques and building materials are helping to cut embodied carbon
Real estate doesn’t just need to decarbonise its day-to-day operations; cutting the carbon footprint of materials and construction processes is an increasingly pressing issue.
Embodied carbon is responsible for around 10 percent of global greenhouse gas emissions. Each year, more than 6 billion square meters of buildings are constructed using carbon intensive materials such as glass, iron, steel and concrete.
Unlike operational carbon, which can be reduced through energy efficiency measures and using more renewables, embodied carbon is locked into buildings. The World Green Building Council estimates it will account for half of the entire carbon footprint of new construction between now and 2050.
“There’s a growing realization that we need to address embodied carbon if buildings are to reach true net zero,” says Kat West, Vice President of Sustainability, Project and Development Services at JLL. “A move to alternative building materials and new technology, as well as software, is moving the construction industry forward.”
Transformative materials
As the choice of low-carbon materials widens, engineers are increasingly experimenting with less polluting alternatives. In Georgia’s Kendeda Building for Innovative Sustainable Design in the U.S., reclaimed wood from film sets is replacing concrete.
Smart materials such as self-healing concrete, which could mitigate extensive future repairs, or climate-adaptive smart glass, which changes opacity to control the level of light and heat passing through, are being tested.
“It’s a learning curve to know more about materials with lower or no embodied carbon,” says West. “There are now dozens of optimized products that reduce carbon with no added cost.”
What’s more, the development of next generation materials is moving at pace. Graphene, made of a single layer of tightly packed carbon atoms, is 100 times stronger than steel, and can strengthen traditional concrete. With less concrete then required in the construction process, it can cut carbon emissions.
Meanwhile, Martian concrete uses sulphur instead of water to make it more resistant to corrosion, helping buildings to stay in prime condition for longer.
New ways of building
More innovative construction techniques are equally gaining traction. Modular construction, which uses 67 percent less energy compared with traditional methods, allows buildings to be easily adapted throughout their lifecycle while also improving their energy efficiency. With construction taking place offsite, deliveries to site can be cut by up to 90 percent, reducing emissions.
3D printing is also evolving at pace with the focus not only on creating net zero energy homes but also using non-concrete based systems to do so. Mighty Building’s development in Palm Springs, California, for example, has zero-waste construction processes.
The new technology market is becoming competitive, which will fundamentally drive costs down, says Louise Collins, MENA head of engineering and energy at JLL.
“Primarily cost, availability and efficiency will decide how the market will use these new technologies,” she says. “With return on investment considerably shorter than before, this enables developers’ ESG strategies to align with investment. So it’s a win-win for both suppliers and developers.”
Counting carbon emissions
Moe changes to construction processes are happening behind-the-scenes. With building design and maintenance technology becoming ever more sophisticated, engineers can monitor and report carbon emissions both during construction and in day-to-day operations.
Architectural software platforms, for example, help designers adjust both layouts and materials to select the lowest-carbon options. Meanwhile, digital twin models allow full-life carbon performance to be simulated and fed back into building design.
“These are allowing users to understand the impact that optimising their buildings has on their carbon footprint,” says Collins.
“It’s crucial to allow end users to understand where they are on their sustainable journey,” she adds, pointing to tools such as the Athena Sustainable Institute’s EcoCalculator, which takes all stages of construction into account.
Furthermore, each new fit-out renovation or retrofit also offers opportunities to cut embodied carbon.
New databases, such as the EC3 Calculator, an open, free database of building materials launched by Building Transparency, are helping. By showing what a product is made of and its environmental impact, developers and architects can better compare materials and make eco-conscious choices.
“We’re seeing progress but more platforms for carbon counting and carbon reduction reporting will be needed,” says Collins.
Looking to the future
While the pace of innovation is increasing, the speed at which new tech is adopted often comes down to how quickly corporate policies or local legislation are implemented. In Norway and recently in Colorado, embodied carbon legislation has been passed.
“In places where such legislation is implemented, we quickly see people wanting to learn more about and the positive impact on the immediate area is felt soon after,” West says, estimating that 10 percent of projects are now factoring in embodied carbon, from zero just a few years ago.
In the UK, British Land plans to cut its absolute embodied carbon emissions in half by 2030 against a new 2019 baseline.
“But we’re still at an education point,” West adds. “Seeing developers look more at their carbon budget the way they look at their financial budgets, and publish embodied carbon numbers, would be a big step.”
source: https://www.us.jll.com