BioBase 501, Soy-Based Polyurethane Foam
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BioBase 501, Soy-Based Polyurethane Foam
Has this become the standard for spray foam, meaning a soy based product over petroleum based?
Or is it a new fangled tool for marketing.
Anybody know the pros/cons of the various types?
Replies
Mostly marketing. One half of the formula is 100% petroleum based. The other half can only be about 50% soy based. Then consider the fact that the soy and its processing is all done with petroleum driven processes such as the natural gas derived nitrogen fertilizer and the fuel for equipment and you haven't gained much more than a placebo feel good for the client. The downside is that it is slightly less stable and has been known to become a little more likely to crumble with age.
The upside might be to encourage further development of agricultural solutions to our dependence on petroleum.
There will be dissenting opinions. I would take those by bio based installers with a grain of salt. I am a builder and a building scientist. I don't really have a dog in the fight. I have not used bio based foam but have spoken to two installers that can spray either and done some on line research.
Hopefully a chemist will chime in and add another point of view.
Will a chemical engineer do?
You want a "bio-based" insulation? Use cellulose and forget about soy foam.
The polyol resin portion of the polyurethane formula is the part that is replaced by the soy, and this part is already a pretty benign molecule. Granted, it's made by polymerizing ethylene oxide, which no chemical engineer would call benign, but the end product is about as tame as synthetic molecules get. Petroleum based yes, but analogues of these compounds are found in everything from shampoo to milkshakes so what's been gained by substituting soy aside from a coat of "green paint"? You're still using an isocyanate to react with it, and that's the hazardous and energy-intensive (and expensive) part of the polyurethane formulation.
Whatever you use for insulation, the energy input cost of that insulation is dwarfed by the energy savings it provides when properly installed. Since the source of most of that heating energy is fossil fuels, you should choose the best insulation for the job and worry far less about how it's made.
Bravo. I hate the greenwashing that is happening in the industry. It is similar to masturbation in that it feels good but doesn't accomplish much outside of that. Marketing often gets in the way of doing what's right.
I have; however, moved away from cellulose for a number of reasons ranging from performance to moisture issues in my walls during construction.
Thanks for your input.
I asked a local installer about it when he did our roof and he called it "garbage". He's been doing foam since '77 and has tried them all, preferring to spray the NCFI 2.0 cu.ft. product when at all possible.
1/2 lb. has it's place and 2 lb. has it's place. One is not better than the other. I use 95% 1/2 lb. for my projects. For the other 5% of the situations, 2 lb. is the way to go. They have different properties.
Application is everything with foam. The installers can make a huge difference. If they go in and spray the surfaces willy nilly, they may end up with a continuous surface with many concealed voids. If they have the wrong mix or temperature, they will have other problems, including shrinkage or product waste.
We use 2.5# to 2.8# on our stuff. And then complicate it further by spraying it inside a sphere. Takes some real skill to get it even--I've seen huge knots from some guys while others can get it smoother than the skin of an orange.moltenmetal, great explanation of soy, thanks. I may borrow that sometime!
The reason that I posted this was to get some clarification of the longevity of the product when comparing the aples for apples/oranges. So far, I have found only one foam company with in a reasonable distance to where we live in No.Cal. They are located in Sacramento and this is the only product they sell. We don't want to spend money/time on something that will pull away from framing or deteriorate.
I figured that it was better tio check in here first before I talk to that company since, I imagine, they are going to say that their's is the best product.
Our home is a 1930's Tudar that has a bastardized interior framing on the walls and a poorly done insulation some ceilings/walls and none at all in others.
This home probably would do best with foam because of the poor roof venting(almost none) and by the way that the attic space is cut up or non-existant.
Anyway, thanks for the help/responses.