“With buildings currently responsible for 39% of global carbon emissions, decarbonizing the sector is one of the most cost-effective ways to mitigate the worst effects of climate breakdown,” says WGBC in the report, called a road map to achieve net-zero EC in buildings.

Net-zero EC should be pursued as part of a whole life-cycle approach to carbon reduction that includes net-zero operational carbon (OC), says the report.

Published by WGBC’s Advancing Net Zero project, with the C40 Cities Climate Leadership Group, the document sets “achievable” milestones for global net-zero EC, said Cristina Gamboa, CEO of the WGBC. “We believe [the report] is the first of its kind,” she added.

There are more than 85 organizations, including national governments, such as Finland, and think tanks, supporting WGBC’s EC goals, said Gamboa.

WGBC has set forth one major milestone on the way to its over-arching zero-carbon goal. “By 2030, all new buildings, infrastructure and renovations will have at least 40% less EC, with significant upfront carbon reduction, and all new buildings must be” net-zero OC, says WGBC.

By 2050, the same set of buildings “will be” net-zero EC and all buildings, including existing ones, “must be” net-zero OC.

As defined by WGBC, a net-zero EC building, new or renovated, or an infrastructure asset, is “highly resource efficient with upfront carbon minimized to the greatest extent possible and all remaining EC reduced or, as a last resort, offset” to achieve net zero across the building’s life cycle.

WGBC defines EC as all greenhouse- gas emissions associated with materials and construction processes throughout a building’s life. This includes material extraction, transportation to the manufacturer, manufacturing and transportation to the site and construction. The definition also wraps in all post-construction activities, such as maintenance, repair, replacement, refurbishment, deconstruction, transportation to end-of-life facilities, processing and disposal.

The challenges are many, including overcoming resistance to change. “Our sector is highly dispersed and relies on a wide range of materials with long and complete supply chains. Many of the most widely used construction materials are from carbon-intensive heavy industries,” says the report. “To date, very few buildings or infrastructure assets can claim to be fully net-zero embodied carbon and in line with our vision.”

Still needed are major changes in the supply chain, especially to shift toward clean fuels in materials extraction, manufacture, transportation and construction. “Large amounts of additional renewable energy are needed, and some of the solutions we will rely on are currently only at the demonstration stage,” says the report.

In addition to sounding the alarm and stimulating market demand through collective action, the report is intended as advocacy for local EC policy and regulation.

“We do recognize we can’t do this shift on our own,” said Lena Hök, senior vice president for sustainability at developer-builder Skanska. “We’re still a business and need to develop market solutions,” she added.

Others agreed. “We need government incentives,” such as additional floor area for new buildings that demonstrate reduced EC, said Robert Ward, Skanska USA’s president and CEO for commercial development.

Lars O. Riemann, executive director of environmental engineer Ramboll Buildings, the report’s technical consultant, added, “We need to create a market for low-carbon products and we need government regulations and carbon budgets for industrial emissions. Without regulations, change will happen slowly.”

Cities should lead the way, proving the case for the private sector and institutional builders with EC-reduction pilot projects for municipal buildings, said Laura Jay, deputy regional director for North America of C40 Cities—a network of 94 mayors of the world’s largest cities. 

But before regulating, cities want certainty from the market as to what is deliverable, said Jay. Toward this end, “there needs to be a dialogue” between elected officials and industry to determine achievable goals, added Jay.

Then, by collaborating with one another, cities can stimulate demand for clean products and materials, she said.

Twenty-five GBCs and 200 individuals helped create the report. WGBC is not releasing dollar amounts, but the effort was funded by the European Climate Foundation and the Children’s Investment Fund Foundation. Contributors are We Mean Business and the WorldGBC European Regional Network.

Obstacle

One obstacle is that, unlike OC, which refers to greenhouse gases emitted when operating a building, “EC is a little bit of a foreign concept to many people,” said Riemann.

WGBC aims to demystify EC by “breaking down barriers between stakeholders” and mobilizing collective global action. Stakeholders include nongovernmental organizations, buildings-related groups—such as the Carbon Leadership Forum, researchers, policy makers, investors, developers, designers, material manufacturers and contractors.

The report has been endorsed by contractors, such as Multiplex, Royal BAM and Skanska. Skanska recently announced its own new targets to cut emissions by 50% by 2030 and to be net-zero carbon by 2045. “This shows that [a market leader is] ready even to exceed the global vision set out in our report,” said Angela Howarth, WGBC’s marketing communications director.

A tool is coming to aid building teams with same-material—such as steel to steel—and same-product comparisons of EC in goods from different suppliers. Called the Embodied Carbon in Construction Calculator, EC3 is on course for a launch at Greenbuild 2019, Nov. 19-22, in Atlanta. It is an open-source digital tool, free for all to use, that aggregates data on products, materials and processes, said Ward.

“I support the call to action by the World Green Building Council,” said Finland’s Mikkonen. “Reducing embodied carbon should be the new normal.”