{"id":206663,"date":"2023-10-13T16:00:46","date_gmt":"2023-10-13T20:00:46","guid":{"rendered":"https:\/\/www.constructionspecifier.com\/?p=206663"},"modified":"2023-10-17T15:07:15","modified_gmt":"2023-10-17T19:07:15","slug":"evolution-of-sustainable-construction-from-leed-to-federal-mandates","status":"publish","type":"post","link":"https:\/\/www.constructionspecifier.com\/evolution-of-sustainable-construction-from-leed-to-federal-mandates\/","title":{"rendered":"Evolution of sustainable construction from LEED to federal mandates"},"content":{"rendered":"
\"551<\/a>
551 Elm apartment building in Chicago.<\/span>Photo by Sarah Crowley. <\/em><\/span><\/figcaption><\/figure>\n

By Emily Lorenz, PE<\/strong><\/p>\n

With the signing of the Infrastructure Investment and Jobs Act<\/em> (IIJA<\/em>)1<\/sup> and the Inflation Reduction Act<\/em> (IRA<\/em>),2<\/sup> federal funds for infrastructure construction and low-embodied carbon materials will soon be entering the construction pipeline.<\/p>\n

An environmental product declaration (EPD) discloses the environmental impacts of a construction material or product over a portion of, or all of, its lifetime. This makes it possible to understand the relative impact of different products and materials. EPDs allow a manufacturer to be transparent with interested parties, such as architects, designers, and specifiers, about its products\u2019 environmental performance.<\/p>\n

Precast concrete is in a unique position because precast concrete projects are built to last longer than other construction materials. This means considerations other than cradle-to-gate environmental impacts typically reported in an EPD should be evaluated. Cradle-to-gate encompasses the production stage of the lifecycle stage, or modules A1 through A3 (see \u201cLifecycle stages\u201d sidebar on page 30). Frequently, the overall lifespan of a building must be considered to understand the full environmental impacts of design decisions. Thus, a full lifecycle assessment (LCA) of a building is necessary.<\/p>\n

From voluntary transparency to government mandate<\/strong><\/p>\n

Initial awareness of sustainable design and construction in the U.S. can be attributed to the Leadership in Energy and Environmental Design (LEED) rating system, embraced primarily by architects in the design and construction communities. Other voluntary programs have been launched over the last 15 to 20 years, such as the Green Building Initiative\u2019s (GBI\u2019s) Green Globes and the International Passive House Association (iPHA), but none have matched the reach and influence of the LEED rating system.<\/p>\n

When the construction industry first started responding to requests for the environmental impact of products, the requests were typically coming from architects wanting to know the recycled, biobased, or regional material content of products. This information was used to document requirements in the LEED rating system, then used to achieve points and ultimately a rating of the final structure.<\/p>\n

As the LEED rating system evolved, submittal requests expanded to include requests for EPDs. Through this voluntary program, manufacturers were encouraged to create EPDs in order to transparently report the potential environmental impacts of their products. Manufacturers were further encouraged to produce plant-specific EPDs by rewarding their \u201cvalue\u201d as twice than that of an industry average EPD toward the number of points or products required. (See more on industry-average versus plant-specific average in the \u201cEPD Basics\u201d section).<\/p>\n

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\"Global<\/a>
Global warming potential (GWP) of the fifteen buildings for each of the four cities for the cradle to gate analysis.11<\/sup><\/span>llustration courtesy Precast\/Prestressed Concrete Institute (PCI). <\/em><\/span><\/figcaption><\/figure>\n

The LEED program moved the needle toward more sustainable products and increased transparency as architects incorporated LEED requirements into project specifications. Although a voluntary program, by implementing requirements into the specifications, product manufacturers had to comply regardless if they wanted to supply products to LEED projects. Thus, LEED was highly influential in raising awareness in the construction industry to topics such as EPDs and environmental impacts.<\/p>\n

The latest push toward product transparency is coming from all levels of the government. Starting from the top, in December of 2021, the Biden administration issued Executive Order (EO) 14057, Catalyzing Clean Energy Industries and Jobs Through Federal Sustainability<\/em>.3<\/sup> This order sets government-wide goals for federal agencies related to reducing greenhouse gas (GHG) emissions, transitioning to carbon-pollution-free electricity and zero-emission fleets, achieving net-zero-emission buildings, and incorporating sustainable acquisition and procurement practices, among others.<\/p>\n

Two pieces of legislation were passed that allocated funding to assist in meeting the requirements of EO 14057, the IIJA<\/em>1<\/sup> and the IRA<\/em>.2<\/sup> The IIJA<\/em> allocated funding focused on three main areas: repairing transportation projects; improving the resilience of infrastructure to climate change, cybersecurity risks, and other hazards; and implementing quality internet service more equitably. \u00a0Funding through the IIJA<\/em> is targeted toward states, local, and tribal agencies, and is less prescriptive than the funding allocated in the IRA<\/em>.<\/p>\n

As part of the IRA<\/em>, federal agencies were allocated funding for the use of low-carbon materials. The U.S. General Services Administration (GSA) was allocated $2.15 billion to support the installation of low-embodied carbon-materials on construction and renovations projects, while the Federal Highway Administration (FHWA) was allocated $2 billion to facilitate the use of construction materials and products that have substantially lower embodied GHGs.<\/p>\n

To assist in meeting the requirements of the IRA<\/em>, the U.S. Environmental Protection Agency (EPA) was charged with setting the definition of \u201clow-embodied-carbon materials.\u201d EPA issued its initial determination of \u201clow embodied carbon\u201d in December 2022,4<\/sup> using a quintile approach. For the purposes of meeting the IRA<\/em> requirements, EPA states low-embodied-carbon materials are those in the lowest 20 percent percentile of global warming potential (GWP) values when evaluating all possible materials in a product category (relative to the industry average).<\/p>\n

GWP, also referred to as climate change potential, \u201cdescribes potential changes in local, regional, or global surface temperatures caused by an increased concentration of GHGs in the atmosphere, which traps heat from solar radiation through the \u2018greenhouse effect.\u201d5<\/sup> The gases CO2, methane (CH4<\/sub>), and nitrous oxide (N2<\/sub>O) are some of the GHGs grouped together in the GWP impact category. GWP is reported in units of kilograms of carbon dioxide equivalent (CO2e).<\/p>\n

GSA was the first federal agency to issue draft guidelines related to low-embodied-carbon materials and IRA<\/em> funding. It issued the draft IRA<\/em> Low Embodied Carbon Material Standards for concrete, asphalt, steel, glass, and cement in January 2023 with a request for information (RFI) to stakeholders. As of July 2023, GSA\u2019s revised IRA Low Embodied Carbon Material Standards for concrete, asphalt, steel, glass, and cement have not been released.<\/p>\n

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\"The<\/a>
The Jasper was a co-winner in the \u201cBest Mixed-Use Building\u201d category in the 2023 Precast\/Prestressed Concrete Institute (PCI) Design Awards.<\/span>Photo courtesy Inspiro 8 Studios.<\/em><\/span><\/figcaption><\/figure>\n

The basics of EPDs<\/strong><\/p>\n

In order to qualify as a low-embodied-carbon material and be selected for projects for which GSA and other federal agencies are using IRA<\/em> funds, manufacturers must create EPDs to show their GWP.<\/p>\n

To understand how EPDs are created, one must understand LCA. LCA is an analysis method developed to, among other things, allow the evaluation of the potential environmental impacts of a product system. Through the use of LCA, models are built of the product system to account for material and energy flows through a system boundary, which are then characterized into potential environmental impacts. Changes to that product system can be evaluated to determine if they improve or worsen the environmental impact of the product. Two standards are used to perform LCA: International Organization for Standardization\u2019s (ISO\u2019s) ISO 14040, Environmental management\u2014Lifecycle assessment\u2014Principles and framework<\/em>,6<\/sup> and ISO 14044, Environmental management\u2014Lifecycle assessment\u2014Requirements and guidelines<\/em>.7<\/sup><\/p>\n

\"Figure<\/a>When an LCA is conducted, there is flexibility in the scope of the assessment. One of the more-important scope decisions relates to the lifecycle stages evaluated. Figure 1 shows how various lifecycle stages are categorized in the life of a construction product. At a minimum, all EPDs include lifecycle modules A1, extraction and upstream production; A2, transport to factory; and A3, manufacturing. These modules encompass the \u201ccradle-to-gate\u201d impacts of a product.<\/p>\n

When an LCA report is developed for a given study, it includes a significant amount of information about the product system and its potential environmental impacts. However, given the complexity of an LCA report, it is not necessarily useful for communicating the potential environmental impacts of a product, which is why EPDs are developed. EPDs are also known as Type III environmental labels (according to ISO 140258<\/sup>) that report a peer-reviewed summary of the results of an LCA.<\/p>\n\n\n\n\n
\u00a0LIFECYCLE STAGES<\/strong><\/span><\/td>\n<\/tr>\n
There are four lifecycle stages according to the International Organization for Standardization (ISO) 21930 are: production, construction, use, and
\nend-of-life.9 Each lifecycle stage is subdivided into the following modules:
\n\u2022 Production: Extraction and upstream production (A1), transport to factory (A2), and manufacturing (A3).
\n\u2022 Construction: Transport to site (A4) and installation (A5).
\n\u2022 Use: Use (B1), maintenance (B2), repair (B3), replacement (B4), refurbishment (B5), operational energy use (B6), and operational water use (B7).
\n\u2022 End-of-life: Deconstruction\/demolition (C1), transport to waste processing or disposal (C2), waste processing (C3), and disposal of waste (C4).<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

To create an EPD, an LCA practitioner must use several standards:<\/p>\n