Global Warming Potential for XPS vs EPS in 2023
rossn1
| Posted in General Questions on
With the recent re-formulations of XPS and blowing agents, is there still a significant environmental advantage to using EPS over XPS?
It sounds like in the world of XPS, the OC Foamular 250 (NGX) may be less environmentally impactful than Dow Dupont Gray or Kingston Greenguard? Unfortunately, I need to make a custom order to get EPS.
My application for the insulation is a radiant flooring concrete-over pour all on top of a below-grade uninsulated slab, zone 6A.
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Replies
Have you looked into reclaimed foam? Several years ago, we used 4" thick reclaimed XPS under the slab. Other than a little dusty, it was like new. In Maine, reclaimed foam is usually available through Craigslist.
The NGX HFO-based blowing agents are still much worse from a GWP perspective than EPS. More than double the intensity rate for the same surface area and R-Value. It depends on which EPS manufacturer you are considering, but all you have to do is look for their environmental product declaration (EPD) paperwork and compare it to NGX. Whether this is an important factor in your purchase decision is up to you.
Foamular NGX 250 EPD: https://dcpd6wotaa0mb.cloudfront.net/mdms/dms/Shared/10024576/FOAMULAR-NGX-XPS-Insulation-EPD_UL_corrected.pdf?v=1646664386000 (page 17, table 9)
EPS EPD: https://www.efficiencyvermont.com/Media/Default/docs/white-papers/20210122-GHG-RNC-final-report.pdf (page 7, Table 1)