Climate change has been on the minds of leaders across every industry, and construction is no exception. The buildings and construction sector accounted for 35 percent of final energy use and 38 percent of total global energy and process-related carbon dioxide emissions in 2020.
As more and more mandates go into effect regulating the use of greenhouse gases and unsustainable building practices, insulation has been met with new, if uneven, mandates limiting and prohibiting the use of products that have high global-warming potential.
What is GWP?
GWP, or global-warming potential, is the system developed to allow for comparisons of the global-warming impacts of different gases. According to the U.S. Environmental Protection Agency (EPA), GWP measures how much energy the emissions of 1 ton of a gas will absorb over a given period of time, relative to the emissions of 1 ton of carbon dioxide (CO2). The larger the GWP, the more that gas warms the Earth compared with CO2 over 100 years. One ton of CO2 has the GWP rating of 1. Essentially, it is a product’s carbon footprint.
Regulations have been enacted on a statewide and local basis phasing out or banning the use of products with high GWP ratings, such as those that contain hydrofluorocarbons. These regulations are part of an ongoing effort to help reduce the use and emission of heat-trapping chemicals that contribute to climate change.
“Right now, those regulations are in individual states versus federal regulations,” explains Dave Caputo, global platform director for Owens Corning. “This really started when the U.S. pulled out of the Paris Climate Agreement. A group of states formed a bipartisan and non-binding coalition called the Climate Alliance.” Of the 24 states in the Climate Alliance, nine have now put into place regulations banning or phasing out hydrofluorocarbons, with two more going into effect in January 2022.
Hydrofluorocarbons (HFCs) are a group of widely used blowing agents in closed-cell spray foam insulation and are known for their particularly high GWP. The blowing agent in spray foam insulation and extruded polystyrene (XPS) transforms HFCs from solid polyurethane into foam, giving foam structure and R-value. This is what creates the bubbles of air that make foam a good insulator. The HCF blowing agent, HFC-134a, has a GWP of 1,430, meaning it traps 1,430 times as much heat as carbon dioxide does over 100 years.
“This obviously is a big change for our industry because the blowing agent is a key part of that recipe and does contribute to many physical properties of insulation, whether it’s moisture properties, a high R-value per inch, compression strength and things that other insulation types don’t have,” Caputo says.
Different Options, Different Values
Perhaps the best-known, low-GWP insulation product on the market is fiberglass, as it is manufactured without captive blowing agents. It is also the material that insulation systems compare their product against, and it has been an industry standard for decades.
“It has very low natural and embodied carbon,” explains Ted Winslow, brand product manager for CertainTeed. “We have lifecycle assessment and environmental product declarations for all of our fiberglass insulation products.” CertainTeed’s newest product, InsulPURE, is a fiberglass insulation product redeveloped from an older fiberglass product to reduce raw material, make installation easier and perform better without formaldehyde, while also meeting the GREENGUARD Gold standard for VOC emissions.
Fiberglass is known as one of the cheapest products to use for insulation as well as being durable, corrosion resistant and fire resistant. However, fiberglass’ natural low-GWP may be offset in comparison to other products, as it requires more product to reach the same R-value and may not provide long-term thermal performance due to its vulnerability to moisture. Fiberglass is also energy-intensive to manufacture, creating a higher embodied carbon cost.
Unlike products that use HFCs, fiberglass manufacturers have had to look more at the lifecycle of their product rather than the materials in it. “We’re looking to set benchmarks in terms of what is our water usage? What is our energy usage? And then working towards ways in which we can shift the contribution in a positive direction to even how we manufacture a product,” Winslow says. He also adds that CertainTeed incorporates recycled glass whenever possible in order to cut down on supply-chain emissions required to extract and process minerals for the glass, as well as improve energy efficiencies in the plants.
In direct response to HFCs starting to be prohibited, many manufacturers have turned their attention towards finding a new blowing agent. “Our legacy formula [had a GWP of] around 750,” Caputo says. Owens Corning’s latest product, Foamular NGX Foam Board, was released Jan. 1, 2021, and now delivers a 90 percent reduction in GWP compared to their legacy products. “Now we’re using hydrofluoro-olefins (HFOs), and HFOs have a very low global-warming potential. The blend we’re using now takes that 750, and it brings us down to somewhere around 70 to 80.”
Hydrofluoro-olefins (HFOs), when compared to hydrofluorocarbons (HFCs), have a short atmospheric lifetime, a negligible effect on the ozone layer and, standing alone, a GWP near 1. The R-value of 5 per inch that is standard in the Owens Corning legacy products will remain in the NGX line as well. However, due to HFOs costing more to produce, costs at this time are higher than the legacy products.
DuPont recently released an updated version of its Blue Styrofoam Brand XPS line, transitioning from an already lower GWP product to one that uses HFOs in the blowing agent blend for its Gray Reduced GWP XPS product. “The headline for us is, for our styrofoam products from blue to this new gray, it’s like a 94 percent reduction in embodied carbon—which means we were starting life in blue at 103 [or] 104, take 94 percent away, and you’re left with 6.2,” says Alan Hubbell, DuPont’s residential marketing leader for North America. “And we maintain the same low moisture absorption, strength, rigidity [and] flatness; all those things come into play in the application for use in the field, and those are the things we’re trying to maintain.”
Spray foam, compared to other products, creates a seamless installation and air-and-vapor barrier that prevents moisture, air and thermal movements. Spray foam keeps building envelopes in better condition for longer and, thus, allows buildings to have longer lifespans.
“These spray foam products can decrease energy consumption in structures up to 40 percent,” says Maxime Duzyk, director of building, science and engineering for Huntsman Building Solutions. Huntsman’s HeatLok HFO Pro and HFO HighLift both have an R-value of 7.4 per inch, one of the highest in the industry.
More than GWP
In addition to the GWP of a product, architects and contractors are looking at other aspects of what makes a product sustainable or more environmentally friendly. Environmental Product Declarations (EPDs) are independently verified documents based on international standards that report the environmental impacts of a product. EPDs track supply-chain product data and compare the products’ functional equivalency.
“EPDs are now the tool that is used and requested by architects and designers to choose the most sustainable solutions,” explains Mickel Maalouf, LEED Green Associate and senior representative of sustainable building science for Huntsman Building Solutions. “Previously, different manufacturers could make up their own lifecycle assessments (LCAs), and different non-governmental organizations did their own lifecycle assessments to compare products. They could pick and choose what they wanted to compare and what to leave out; there was no real accountability and no real comparability of information. Nobody verified their methodology or results. EPD is a tool to make sure that everything is externally verified and transparent.” EPDs are also the only tool accepted by LEED as an environmental impact disclosure tool.
Besides GWP, EPDs track lifecycle assessment data such as the effects of extracting and processing the materials to create the product and transporting and manufacturing the product, as well as the carbon emissions from use of the product and end-of-life (i.e., the demolition and waste processing of the product) and any beyond life reuse, recycling and/or energy recovery.
“As the embodied carbon discussion ramps up, there are more folks realizing that when a product lands on a jobsite, it has a certain amount of carbon built into it. When we talk about carbon, we talk about total carbon, a combination of embodied and operational,” says Jeffrey Hansboro, DuPont’s global advocacy and strategic partnerships director. “It’s critical for everybody in the building construction industry to really understand and speak the language instead of just considering one over the other,” he adds.
With so many different options, different acronyms and different components to consider, it’s easy to get lost and reach for the legacy products that people are used to. “We’ve had an aggressive campaign with the architects and specifiers in addition to the contractors and the distributors,” Caputo says. “A lot of times it’s more about driving awareness to the regulation; and with specifiers, it’s about not only that but also articulating for them just what this really means in terms of their structure, the bill process and some of the impact that using our new Foamular NGX versus some of the legacy products can have.”
CertainTeed, Owens Corning, Huntsman and DuPont all stated that they’ve made concerted efforts through “lunch-n-learns,” distributor trainings and website resources to promote the use of low-GWP products and the benefits they have, besides following the new regulations.
“Quite frankly, this is probably the biggest challenges in terms of when you talk about sustainability and you talk about environmental product declarations, and what they mean and what they understand,” Winslow says. “I think the end goal is getting towards having like a nutrition facts type [of] label when it comes to the green contribution of products and buildings.” QR