The Expectation of Carbon-Neutral Design
Climate change is a hot topic…and with good reason.
Signed in 2016, the Paris Agreement sits at the center of the fight against global climate change. Ultimately, its end goal is to ensure that global temperatures don’t rise more than 2° C above pre-industrial levels. Reaching 2° C could mean catastrophic weather outcomes like drought, floods, extreme heat, and poverty for millions of people. The “point-of-no-return” date for a global transition to clean energy sources is 2030.
And while the Paris Agreement sets a 2 degree rise in temperature as the limit, a recent report by the Intergovernmental Panel on Climate Change (IPCC) challenges that. Last October, the IPCC warned us that an increase of just 1.5° C is enough to cause those major impacts across the globe.
Today, we’re currently at 1° C above the pre-industrial benchmark.
The push for reducing greenhouse gas emissions is top priority, and the building industry, one of the top contributors of those emissions, must step up. Approximately 33% of energy used in North America is attributed to heating, cooling, and operating buildings.
Architects play a key role as influencers in the design of carbon-neutral buildings. Organizations like Architecture 2030 challenge architects to “rapidly transform the global built environment from the major contributor of greenhouse gas (GHG) emissions to a central part of the solution to the climate crisis.”
In response to the Architecture 2030 challenge, the American Institute of Architecture (AIA) sets the goal to design “carbon neutral buildings, developments, and major renovations by 2030.”
Three steps to becoming carbon neutral.
- Energy Efficiency: Plan energy efficiency over the life of the building including active and passive techniques to satisfy the building’s energy needs.
- Meet with engineers and energy modelers at the design stage about insulation, ventilation, reducing the HVAC load, and the use of renewable energy sources like solar energy.
- Consider the building’s orientation and how it faces the sun throughout the day.
- Choose windows that offer technology that helps keep the building warm in the winter and cool in the summer.
- Embodied Carbon: Reduce the embodied carbon within building materials. Embodied carbon refers to all the non-operational carbon emissions in a building project: emissions that result from the manufacturing, transportation, construction, maintenance, and removal of the materials needed for a project. These carbon emissions are already locked (or ‘embodied’) into the total carbon cost of a building. Ask yourself:
- What are the manufacturing processes of the materials that I specify? Are those manufacturers taking steps to reduce their carbon emissions?
- How much waste is created from manufacturing of my selected materials, and is the waste recycled?
- How far do the materials travel to get to my job site? Can I choose a manufacturer that is closer to reduce the carbon emissions of transportation?
- Carbon Offsets: Even with renewable energy sources and conscious material selection, some carbon emissions remain. Balance the remaining carbon emissions of the building with carbon offsets (also known as carbon credits). This is the last step to carbon neutrality. Carbon offsets are actions in the community or around the world that prevent, reduce, or remove greenhouse gas emissions. For example:
- Plant trees in reforestation programs. These programs offer carbon-neutrality credits like Verified Carbon Units (VCUs) that count toward offsetting your buildings emissions.
- Invest in renewable-energy programs like wind farms to receive credits.
Should You Renovate or Build New?
Renovating an existing structure significantly reduces carbon emissions compared to tearing down and building new.
The sheer amount of carbon used to originally build a foundation, envelope, and structure are simply too great to justify a demolition. Carbon-conscious retrofits can end up saving 50-70% of embodied carbon.
Plan It for the Planet
The expectation for today’s architect is to design carbon-neutral buildings and renovations. The key word in meeting this expectation is planning. Taking the purposeful steps at the beginning, with engineers and energy modelers, to select renewable energy sources, understand the background of the materials specified, and offset remaining carbon emissions will deliver that expected carbon-neutral project.