Greenhouse gases in construction: Of those total emissions, building operations are responsible for 27% annually. while building materials and construction (typically referred to as embodied carbon) are responsible for an additional 20% annually.
Existing Building Actions
Achieving zero emissions from the existing building stock will require accelerating the rate and depth of energy upgrades by leveraging building intervention points.
Energy Upgrades
For full building sector decarbonization, every existing building will need to undergo energy upgrades involving a combination of improvements in the energy efficiency of building operations, a shift to electric or district heating systems powered by carbon-free renewable energy sources, and the generation and/or procurement of carbon-free renewable energy.
Intervention Points
Building intervention points occur at point-of-sale; major renovations; building systems, materials, and equipment replacements; capital improvement cycles; zoning or use changes; and life-safety and resiliency upgrades (e.g. seismic, flooding, fire prevention, power disruption).
By aligning energy upgrades with market-driven intervention points the cost and disruption to building owners and users can be significantly reduced.
Intervention point-aligned energy upgrades also catalyze expanded markets for building renovations and carbon-free renewable energy generation that stimulate a sustained increase in local jobs, market growth, and tax revenue.
NEW CONSTRUCTION
Global building floor area is expected to double by 2060.
To accommodate the largest wave of urban growth in human history, we expect to add 2.4 trillion ft2 (230 billion m2) of new floor area to the global building stock, the equivalent of adding an entire New York City to the world, every month, for 40 years.
Achieving zero emissions from new construction will require energy-efficient buildings that use no on-site fossil fuels and are 100% powered by on- and/or off-site renewable energy.
EMBODIED CARBON
When we look at all the new construction that is projected to take place between now and 2040, we see the critical role embodied carbon plays.
Unlike operational carbon emissions, which can be reduced over time with building energy upgrades and the use of renewable energy, embodied carbon emissions are locked in place as soon as a building is built. It is critical that we get a handle on embodied carbon now if we hope to achieve zero emissions by 2040.
Greenhouse gases in construction
Achieving zero embodied emissions will require adopting the principles of:
Reuse, including renovating existing buildings, using recycled materials, and designing for deconstruction.
Reduce, including material optimization and the specification of low to zero-carbon materials.
The sequester includes the design of carbon sequestering sites and the use of carbon sequestering materials.
Just three materials – concrete, steel, and aluminum – are responsible for 23% of total global emissions (most of this is used in the built environment).
There is an incredible opportunity for embodied carbon reduction in these high-impact materials through policy, design, material selection, and specification.
