Building Materials Are Evolving

‍Fifth Wall Newsletter: https://mailchi.mp/fifthwall/reinventing-building-blocks-for-future-green-cities 

It’s likely that you’ve seen us tout this stat before: Real estate accounts for 40% of CO2 emissions. Part of that percentage includes the making of materials needed to build cities. Concrete, steel, glass, bricks and more. Decarbonizing these materials is necessary for a net-zero world. 

As Fifth Wall’s co-founder and managing partner Brendan Wallace writes, “Maybe concrete and steel's climate impact surprises you. Maybe you've read my posts before... I want to see climate activism, attention, and investment go beyond the popular things like electric vehicles and sustainable packaging. There's no way we reach our climate goals without solving for difficult-to-decarbonize industries like concrete and steel.”

So what’s changing? How do these materials go green?

Bricks

• Brickmaking accounts for 2.7% of the world’s carbon emissions. New techniques, like using recycled glass or mining waste can translate into less firing and minimize raw materials—both good for decarbonization.
• Scaling these techniques can be tricky but it shows pulling from the past can inform the future. “Taking clay, mixing it with straw, casting it into blocks and then just leaving it there is biblical-level technology,” one brick maker told Bloomberg.

Concrete

• Concrete is a heavy emitter of carbon. So, researchers are looking at how alternative chemical processes as well as organic binders like mushrooms, hemp and discarded oyster shells can help decarbonize the material's manufacturing.
• What else? It's possible to inject liquid carbon dioxide into a barrel of concrete which could offset 4-6% of a building's carbon emissions.

Steel

• Steel is needed in cities of the future—they'll house batteries for EVs and support wind turbine towers. But it's a major source of carbon emissions.
• The ultimate objective is green steel produced with clean hydrogen energy. A handful of startups are working on this, including one from Sweden which plans to bring fossil-fuel free steel to market by 2026.

For more on wood, asphalt, glass check out the Bloomberg feature here.