Source:Victor Olgyay, Anish Tilak, Connor Usry
Today, the White House took a major step to reduce a pervasive yet often overlooked source of greenhouse gases (GHGs) locked into buildings before anyone steps foot inside — also known as embodied carbon. The announcement of an ambitious set of “Buy Clean” recommendations will advance green building materials procurement for federal building and transportation projects. As a knock-on, it will turbocharge nationwide demand for low-carbon versions of concrete, steel, asphalt, and flat glass.
The US federal government is the largest consumer in the world, spending more than $650 billion on products and services each year. Given its massive portfolio of buildings nationwide, totaling 2.8 billion square feet, the push to procure low-carbon building materials will help dramatically reduce GHG emissions locked up in the walls, foundations, and ceilings of both new and existing properties. The move will also help meet US goals of achieving net-zero GHG emissions by 2050.
The new recommendations — shared today by Transportation Secretary Pete Buttigieg at a low-carbon iron ore processing facility in Toledo, Ohio — leverage the government’s vast purchasing power to drive demand for low-carbon material products. The new standards also catalyzes increased measurement and disclosure of GHG emissions by manufacturers, supports the growth of a clean energy economy, and boosts growth in jobs and investment in related innovations.
Structural materials such as concrete and steel are major drivers of climate pollution from buildings. Combined, they represent more than 60% of embodied carbon emissions for US federal buildings. In particular:
- Concrete is the second most used material on the planet, trailing only water. It accounts for at least 7 percent of carbon emissions worldwide, mostly due to the GHG-intensive process of creating cement, the key binding material in concrete. Cement plants are also a significant source of sulfur dioxide, nitrogen oxide, and carbon monoxide, a trio of pollutants which can contaminate water and trigger asthma and cardiovascular disease.
- Steel production is similarly carbon intensive. Annually, the steel sector emits around 7 percent of global emissions. If not abated, steel production likewise emits a host of harmful air pollutants.