This Is How Amazon Is Reducing Its HQ2's Carbon Footprint

A bevy of new contech tools are being introduced to help builders evaluate the life-cycle “embodied” carbon footprints of building materials in order meet carbon reduction goals ESG-minded investors and developers are aiming for in new projects.

New “carbon calculators” are being used to measure embodied carbon by tracking how much the harvesting or mining, manufacturing, packaging and transport to the jobsite of specific building materials contributes to global greenhouse gas emissions.

The new tools are helping project managers and builders choose more environmentally friendly building materials, including the low-carbon concrete and mass timber that Amazon now is using to build its massive HQ2 project in Virginia.

California-based contech player Procore recently released its Embodied Carbon in Construction Calculator (EC3). The calculator, co-developed by Skanska and C Change Labs, contains a database of materials and their “embodied” carbon amounts, which allows the user to compare building materials to determine which materials can significantly reduce carbon footprints.

Procore is partnering with the non-profit Building Transparency to integrate EC3 into the non-profit’s platform offering open-access data and tools to enable the building industry to address embodied carbon’s role in climate change.

Clark Construction, the contractor building the first phase of Amazon’s HQ2 project in Arlington, VA is deploying low-carbon materials and new technology to reduce the embodied carbon footprint of the project by up to 25 percent.

Concrete generates an estimated 8% of global carbon emissions. Amazon is using a new technology that reduces the carbon footprint of the 200,000 cubic yards of concrete Amazon will need to complete the HQ2 project by injecting carbon dioxide into the concrete.

That’s right: they’re reducing carbon emissions by adding carbon dioxide to the building materials.

On the first phase of Amazon’s project, known as Metropolitan Park, Clark is using a product known as CarbonCure, which injects a precise dosage of captured carbon dioxide into concrete during the mixing process, where it mineralizes.

According to CarbonCure’s website, the added carbon dioxide improves the concrete’s compressive strength, optimizes the mix and significantly reduces the carbon footprint without compromising the structure.

CarbonCure says the mineralized carbon dioxide will never leak out or return to the atmosphere, even if the concrete eventually is demolished.

The massive, $2.5-billion HQ2 project, a mixed-use development that will include two 22-story office towers, 50,000 SF of retail space and a 2-acre public park, also will feature mass timber, which has been used in more than 1,300 building projects since it was introduced in 2013, according to mass timber group WoodWorks.

Mass timber uses thin layers of wood products glued, nailed or doweled together to create large structural components, including the 14,000-pound timber beams that are being used to build a 700-person-capacity event space at HQ2.