Global warming potential of SPF products
I’m admittedly only nominally aware of the potential for certain spray polyurethane foam products to contain materials (in the form of certain blowing agents like HFC) which may contribute to global warming. Similar 2-part SPFs are being used by some foundation and highway repair contractors to stabilize soils and subgrades below buildings and highway slabs. Basically these SPFs are injected through drilled ports in a slab or pavement to improve the subgrade bearing capacity, and raise or level slabs which have settled or rotated. If these SPF products do indeed have a high global warming potential, their rollout to state and federal highway repair applications might be significant. I’m aware of one foundation repair company who says they have installed 75000 lbs of SPF in a few very limited highway repair projects. I’ve tried to find whether this product is listed as having HFC blowing agents, but it’s not obvious or evident. Maybe the company doesn’t have to disclose this – I don’t know. I’m no building physicist or scientist – who might be a good resource to ask these questions to? Would the state Dept of Transportation have an agent concerned with whether products they are specifying might have a significant global warming potential?
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Jamie,
For sub-slab or below-ground use, these highway departments are almost undoubtedly using closed-cell spray foam, not open-cell spray foam, because closed-cell spray foam has the required density for this application.
Almost all closed-cell spray foams include blowing agents with a high global warming potential.
I'm pretty sure that the only closed cell spray foam on the market that does not have high GWP is Lapolla 4G. It's only been available for about a year, maybe less. Demilac says they will have one out this year.
If this work could be shifted to use the new products, it could be a quite significant improvement!