The construction industry continues to receive ongoing scrutiny for its carbon emissions. With new regulations and building codes imminent or already in place, the industry as a whole is under pressure to reduce emissions.
Although ready-mix concrete producers play a vital role in the carbon impact of new construction, the truth is, all stakeholders contribute to the result. From the construction materials used, to how they are prepared, transported, and implemented within the project, carbon reduction must be top of mind.
In a recent webinar, Carl Elefante, the 94th President of the American Institute of Architects, shed some light on simple and cost-effective ways to reduce carbon emissions in construction and how all stakeholders can and should work together to build more responsibly.
1. City Administrators
Projects are conceived, designed, and built based on prevailing building codes and zoning rules defined by state and local governments. It’s at this first step of the process—before any ground is broken—that significant efficiencies are achieved simply by creating and appropriately enforcing standards that will contribute to a carbon-neutral result.
According to Elefante, a zero-carbon code will be included in the 2020 code cycle, providing cities with the means to adopt more efficient zoning to save money and reduce emissions.
Along with better zoning and regulations, city administrators can create incentives that make a carbon-friendly approach more feasible for build owners. For example, a city can influence whether an existing building is torn down and built anew, or simply retrofitted. Depending on building type, location, climate, and grid mix, retrofitting a building can save as much as 50-75 percent of embodied carbon emissions versus a new build. This shows that the most sustainable building options are often repurposing existing structures.
As the project owner, the developer sets the vision for design and execution. For example, the developer can incorporate carbon emission-friendly requirements in the scope and bid documents. This communicates the owner’s intent to create a more sustainable project, clarifying expectations for the design team, contractors, and materials suppliers. The likely outcome of taking this approach is that all decisions will be influenced by this vision for a more sustainable product.
One of the most significant choices that a developer can make to influence operational emissions is to specify that the building design incorporates zero-carbon energy sources. If the building can’t produce enough energy to power itself, more can be purchased offsite. There are a range of power supply options, some of which are surprisingly cost-effective. These can also provide more stable cost and supply models versus traditional energy sources.
New tools are also coming online to help developers determine the carbon impact of materials before any work occurs. For example, the EC3 tool provides an estimate of a project’s embodied carbon emissions per material category. These tools can assess the carbon efficiency before the design work is final, ensuring that outcomes are accurately quantified and decisions are informed before moving forward with construction.
3. Design Team
Design has the most significant impact on its carbon efficiency. During the discussion, Elefante noted that simply designing with carbon reduction in mind—without any defined design requirements—can decrease carbon emissions by as much as 15%. Some examples include reducing the number of columns in the design and negative spaces in concrete structures. These are simple yet effective tactics that will not impact creativity or the purpose of the built space.
The building design can incorporate zero-carbon energy sources, including the potential for the building to power itself. These types of zero-energy buildings can provide financial benefits, including utility cost savings of 20% to 50%, a payback between 5 and 10 years, and a first-cost increase of 3% to 5%.
There is a role to play for construction materials in the decarbonization of new construction. Strategies exist for reducing the impact of materials such as steel, concrete, and wood. For example, the use of recycled steel can significantly reduce the emissions of a new building. Concrete—specifically ready mix concrete—also offers unique properties that design teams can harness to reduce the impact of using these versatile materials.
Often considered one of the biggest sources for waste carbon dioxide (CO2) emissions, new advancements in CO2 technology have driven significant improvements in concrete production. Today, with four simple steps, post-industrial CO2 can be beneficially reused in concrete production. This process chemically converts CO2 into a solid mineral in the concrete, permanently removing it from the atmosphere. The mineralization leads to decreased cement requirements and lower emissions per unit of concrete without sacrificing performance characteristics. This leads to a reduction in embodied carbon for new builds, complementing operational emissions reductions achieved through the use of renewable energy and efficient design strategies.
The process can be easily integrated into existing production workflows, providing immediate results, and allowing producers to lower carbon emissions while making stronger and greener concrete.
A Collaborative Mindset
It’s clear the construction industry is undergoing fundamental change. Green power, zero carbon emissions, and sustainable building practices are encouraged, incentivized and, in some scenarios, an absolute requirement.
As a key stakeholder in the build process, ready-mix concrete producers are embracing innovation and defining new standards to support a carbon-neutral result.
Today, administrators at the local and state level are introducing new regulations, with the adoption of different building practices quickly becoming an imperative. By working together, with the benefit of technology and science, all stakeholders can achieve a greener, lower carbon result. Watch the on-demand webinar to learn more.