The Passive House Institute U.S. (PHIUS) has banned the use of spray polyurethane foam (SPF) with high global warming potential (GWP). The discussion on high GWP insulation was elevated in an excellent piece, “Avoiding the Global Warming Impact of Insulation,” written by Alex Wilson, the executive editor of Environmental Building News.
During Passivhaus training last year, it was stated that this could potentially be coming down the pipeline – so we weren’t surprised to see this pending regulation.
In the article, Katrin Klingenberg, the executive director of PHIUS, stated, “It does not make any sense at all to use them if one of the major overarching goals of energy conservation in buildings is to counteract and decrease global warming and climate change. There really is no point to go through all the trouble of detailed Passive House design calculations if you use high-GWP [global warming potential] spray foam.”
A little off-putting
While we completely agree conceptually – there does seem to be something off-putting about banning certain products in a performance metric – especially as the SPF industry is taking steps to lessen the environmental impact of their products. Another EBN article, “New Chemical to Reduce Climate Impact of Foam Insulation,” stated that low-GWP blowing agents were almost market-ready and could be seen in the next 18 months.
One of the things we really like about Passivhaus is that it isn’t green by checklist – that it’s not prescriptive – but really open-ended and up to the designers to figure out the best approach for them to achieve substantial reductions in energy and CO2 emissions.
A slippery slope
If you are wondering why we think this precedent could slow industry adoption, the article goes on to discuss issues of embodied carbon and embodied energy of building materials. Said Katrin, “in the future I would like to add the embodied energy to those balances because of the significance in super-insulation.” And again, we definitely agree designers should take this into account and several (including ourselves, where possible) already do. For many, issues of GWP/ODP/PEI are intricately linked and all should be taken into consideration.
This precedent seems to be a bit of a slippery slope – where should the line be drawn? Who demarcates it? Should XPS and EPS be banned? Should concrete, which isn’t the most environmentally-friendly industrial process, be the next to be axed? Should all wood be FSC certified? What about houses that use granite countertops? Should rural and suburban projects be banned from certification? What about buildings that exceed a planned occupancy of greater than 50m² per person? It is an extremely delicate line, and the attractiveness for many (who were already doing BuiltGreen/LEED projects and incorporating earth-friendlier products) has been the simplicity that has allowed for the somewhat rapid adoption – especially for businesses or industries that can be a bit notorious to resist change.
According to the article, the new SPF rules will be in full effect by January of 2012. Regardless, we will continue to be fierce advocates and infamous cheerleaders for a regional Passivhaus movement that will have a meaningful impact.
Mike Eliason is a designer and certified Passivhaus Consultant at the Brute Force Collaborative in Seattle.
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