Should LEED be in the Lead?

Coming out of the Covid-19 pandemic, governments around the world have taken on a new commitment to addressing the climate crisis. Just within the past year, commitments to achieve net-zero emissions have doubled (“Our Cities” 2022, “Commitments to Net Zero Double in Less Than a Year | UNFCCC'' 2021). In the process of converting these commitments to reality, governments have looked to address a major source of greenhouse gasses: buildings and construction, which account for nearly 40% of global carbon emissions (Lebot 2017). One such method is the incentivization and certification of green buildings.

Green buildings are those designed to reduce or eliminate negative environmental impacts, and are often designated by independent green building certification. These certifications are awarded to buildings which meet certain standards of resource efficiency and sustainability (“Basic Information” 2016).

Independent and governmental certifications can provide a useful benchmark for policymakers to create incentive programs. However, the efficacy of this policy is only as strong as the standards of the certification. Recent studies have shown serious flaws in popular green certifications. Creating effective climate policy to address building emissions will require modifying certification standards or reassessing how these certifications are used.

The most popular of the green building certifications is the Leadership in Energy and Environmental Design (LEED) certification, developed by the United States Green Building Council. LEED certification is a global framework developed for sustainable construction and facilities. It is a design-based system, which awards points for buildings that include sustainable materials, and features of water and energy efficiency (“LEED Rating System” 2016).

Another popular certifier in the US is the EPA’s Energy Star Certification. This certification informs consumers and investors about the energy efficiency of products, manufacturing, and buildings. Unlike LEED, the Energy Star building certification is performance-based, and uses measured energy data. Energy Star scores are based on a building’s efficiency level relative to similar buildings. Additionally, Energy Star certification is reviewed annually and must be recertified year to year (“ENERGY STAR Certification” n.d.).

In the twenty-first century, energy efficiency and climate concerns have led to a rise of programs to incentivize the expansion of green buildings. (US EPA 2015, “Tax Deductions” 2021). However, the cost of verifying environmental benefits has led state and local governments to utilize green building certifiers like LEED and Energy Star as the basis of incentivization programs (Hansen 2014). A number of state policies promote LEED certification by offering low interest loans, tax abatements, and tax credits. Additionally, projects seeking LEED certification can also receive priority permitting and rebated permit costs (Hansen 2014).

These programs are designed to help municipalities meet climate goals by reducing building emissions. However, this is only the case if green certification actually succeeds at lowering the greenhouse gasses produced from construction and operation.

As the number of governments with net-zero commitments increases, policy based on green building certification is likely to grow with it. Yet, a growing body of literature examining green certification like LEED and Energy Star casts doubt on whether their environmental promise is actually realized.

In recent years a number of studies have questioned the efficacy of LEED certifications. Perhaps the most critical shortcoming of the LEED system is that it is not strictly performance-based. Rather, it rewards design criteria with points for different features and modeled energy savings (LEED rating system 2016). As a result, the certification can be “gamed” by developers to maximize their certification points without actually reducing energy, water, or emissions (Schnaars and Morgan 2012).

One study of office buildings in New York City found that overall, LEED certification had no benefit compared to non-LEED buildings. Specifically, only those with LEED Gold Certification showed any efficiency benefit. Those with Silver and Certified status underperformed compared to the average NYC office building (Scofield 2013). Another meta-analysis of forty-four peer-reviewed studies found that even in newer versions of the certification there is extreme variability in the amount of realized energy and emissions savings. The quantity of carbon dioxide avoided per efficiency point varied sometimes by orders of magnitude (Greer et al. 2019). Thus, the delinkage between LEED points and environmental outcomes can make buildings appear more environmentally friendly than they are.

Furthermore, both LEED and Energy Star certification still under-account for embodied emissions. Embodied emissions are those which occur from the production, use, and disposal of an item over its entire lifecycle. In the case of buildings, these include the production and transportation of materials, as well as emissions from construction (“Buy Clean” 2021).

The most recent version of the LEED standards have included more performance measurements and partially address embodied emissions. A specific section for building materials includes points for reusing existing material, renewable materials, and managing construction waste. However, critics argue that they do not accurately reflect the consequences of embodied emissions (Amiri et al. 2021). Energy Star does not include a measure of materials in its building certification, but it does provide efficiency ratings to manufacturing plants (ENERGY STAR Certification n.d.).

Failing to account for these emissions can severely reduce the benefits of green buildings. As a result, for consumers, investors, and policymakers, misleading certifications can hinder climate action (Dahl 2010). However, recent revisions of LEED certification and potential expansion of Energy Star certification offer a solution to this problem.

Green building certification is a tool policymakers can use to meet climate goals. But this tool is only useful if it is accurate, consistent, and effective. In order to efficiently use development incentives, certifications need to be revised or considered only as a baseline. The extreme variability in the emissions impact of LEED points means that policymakers cannot know what effect their incentive programs are actually having. Research indicates that it is only effective to base incentives off Gold certification or higher, as these are proven to result in measurably lower energy use and carbon emissions (Scofield 2013, Greer 2019).

Within the EPA’s own building certifications, Energy Star needs to be revised to include embodied emissions. It currently does this for a variety of different products and manufacturing processes but fails to include these in its building efficiency scores. As a result, while it is effective at measuring operational emissions, it leaves out an important part of a building’s carbon footprint.

In the next few decades, policymakers, developers, and manufacturers will all need to pay more attention to lifecycle carbon emissions. In this time, independent green building certification has an important role to play in measuring and promoting sustainable building practices (Jones et al. 2019). However, certification standards must be continually updated to reflect actual, effective environmental consequences. Without this, policy will be ineffective or even detrimental to climate progress. Incentives for certification will fail to deliver the intended reduction in emissions. And lacking material benefits, certifications may create a false sense of security instead of producing necessary results.