Redesigning insulation for improved sustainability, carbon footprint

Blog in Brief

Regulatory changes brought in Canada and parts of the U.S. seek to reduce the global warming potential (GWP) of materials used in several industries. For the insulation and building sector, this has spurred innovation in blowing agent formulation as work progressed to lower the GWP of ingredients used while maintaining extruded insulation performance characteristics. Reformulation efforts were successful with the creation of FOAMULAR® NGX™ (Next Generation Extruded) insulation. The redesigned insulation provides the same benefits as legacy FOAMULAR® XPS insulation – high R-value, superior moisture resistance and up to 100psi of compressive strength – but has a lower GWP and provides a reduction in the material’s carbon footprint. 

Redesigning Insulation for Improved Sustainability, Carbon Footprint

Originally discussed in 2016, the Kigali Amendment to the Montreal Protocol sought to phase out the use of hydrofluorocarbons (HFCs) the way the original agreement had done with chlorofluorocarbons (CFCs). There was interest in curbing the use of CFCs because of the environmental effect the gases had on the ozone layer. Although HFCs have a limited effect on the ozone layer, they do have high global warming potential (GWP) because they can trap heat in the atmosphere.

In North America, the majority of HFCs are used in refrigeration – the sector accounts for about 45% of amount used.¹ However, the insulation and building industry use about 9% of these gases, predominantly in the blowing agent needed for extruded polystyrene insulation (XPS).¹ This is why it is a concern for organizations, like the National Resources Defense Council, seeking to reduce greenhouse gas emissions and limit the effects of climate change.

Both in response to the regulatory change and guided by a long-term interest in sustainability – as a company and regarding the products the company makes – Owens Corning spent several years developing a more sustainable way to manufacture XPS insulation. The end result of this development process was the creation of a low-GWP formulation of XPS – FOAMULAR® NGX™ – that is manufactured using a polystyrene resin and a proprietary blend of blowing agents.

Regulation change

When the Kigali Amendment was adopted, countries committed to reducing the production and use of HFCs. The goal was to cut reliance by more than 80% in 30 years.² Making the change is predicted to avoid up to an additional 0.5°C of warming by 2100, as it would eliminate 80 billion tons of CO₂-equivalent emissions by 2050, according to the EPA.² The amendment called for developed countries to reduce HFC use starting in 2019, while developing countries have until 2024.

As part of the commitment, Canada saw regulations regarding the allowable GWP level of blowing agents change in January 2021. Multiple states in the U.S. also reduced the permitted level in 2021 and more states are set to have similar requirements take effect in 2022.

Blowing agents and GWP

As the understanding of gases, the ozone layer and the greenhouse gas effect have changed, the types of blowing agents used have shifted to address new concerns. For example, HFC 134a – the blowing agent currently being replaced – was initially introduced because it had less of a negative effect on the ozone layer than CFCs. However, it is now understood that HFCs are a strong greenhouse gas and have a high global warming potential – about 1,430kg CO2 eq.^2,3

The GWP describes how much energy a gas traps in the earth’s atmosphere compared to the energy absorbed by the same amount of carbon dioxide over a 100-year period. So, in general, HFC-134a traps about 1,430 times as much energy as CO₂ would.

To lower the GWP of blowing agents, Owens Corning reduced the use of HFCs, eliminated HCF-134a and turned to blends with HFOs (hydrofluoroolefins). The gases have limited effect on the ozone layer and a GWP close to 1. HFOs, unlike HFCs, see molecules connected with a double rather than a single bond. In the atmosphere, the double bond is more reactive with hydroxyl and other radicals, meaning it can degrade in 20-40 days rather than lingering for years.

Material innovation

Now that there are commercially available products that provide the same qualities of legacy FOAMULAR® XPS but have an even lower GWP, one may think it was a simple swap in, swap out process for finding a new blowing agent. However, the process was not a simple or straightforward one. It was a six-year journey that included testing almost 100 different blends and blowing agents before the right combination and proprietary manufacturing system was created.

A goal during the development of FOAMULAR® NGX™ was that the redesigned insulation maintains the same properties that the legacy product had, just with a lower GWP. With legacy FOAMULAR® XPS insulation, a 1m² piece with an RSI=1 had a total GWP of 57.8kg CO2 eq. The new FOAMULAR® NGX™ provides a reduction of greater than 80% in comparison, meaning a 1m² board with an RSI=1 had a total GWP of 9.77kg CO2 eq. The reduction in GWP means the insulation qualifies for 1.5 products towards LEED 4.1 points for Options 1 and 2.

Along with the reduction in GWP and elimination of HFC 134a, FOAMULAR® NGX™ still provides a high R-5 per inch and can maintain performance over time. The insulation carries a lifetime warranty guaranteeing that it will keep at least 90% of its R-value for the lifetime of the product. It is available in a range of compressive strengths up to 100 psi, meaning the insulation can be used in a wide range of projects, from exterior wall envelopes to vegetative roof assemblies that manage planted gardens and traffic. Additionally, the closed-cell insulation has a structure that resists moisture penetration and a hydrophobic nature, meaning it sheds water.

The reduction in GWP is not the only sustainable attribute of the insulation. The material is manufactured using 100% wind-generated electricity and contains at least 20% recycled polystyrene – certified by Scientific Certification Systems. Using FOAMULAR® NGX™ in place of legacy types of XPS insulation provides a reduction in CO2 emissions noticeable enough that, for every 10 boards used, it equates to taking the emissions from one car off the road for a year.⁴

Check out the FOAMULAR®NGX™ page for a calculator that provides a look at potential emission savings for a range of example commercial projects.

Conclusion

In developing low-GWP FOAMULAR® NGX™ insulation, Owens Corning progressed the company’s sustainability mission by developing a product that addresses climate change in two ways – the product itself is more sustainable and has a smaller carbon footprint, and it can be used by individuals to reduce their own energy expenditure.

Looking forward, Owens Corning’s focus on sustainability includes further innovation in XPS and has been prompting research into areas beyond work with XPS. At Owens Corning, sustainability is not just a product but a culture. This includes reducing energy usage and waste at World Headquarters offices all the way to reducing packaging waste and exploring recyclability of all products through our circular economy mission within the sustainability department.

For more information on FOAMULAR® NGX™ and the changing regulatory standards, listen to the above podcast.

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