Question from gayle
We are looking into building a “Green” home and a builder we interviewed uses “SIPS”. They told us of the structural advantage, as well as how it keeps heating and cooling cost down as they make the house very air tight.
What is known about this material? How long has it been used? What are the drawbacks?? Anything new scares me as I don’t want to go with it and learn ten years from now that it’s the “new asbestos”. Any information is greatly appreciated!
Thanks,
Gayle
Debra’s Answer
Structural insulated panels (SIPs) are a composite building material, a sandwich of two layers of structural board with an insulating layer of foam in between (you can see a good picture of in on the website of the Structural Insulated Panel Association). The board is usually oriented strand board (OSB) and the foam either some type of polystyrene or polyurethane foam.
While these perform well with regards to saving energy, they are not a good material with regards to toxicity. I was about to just comment on the materials themselves, but then I found a paper called Structural Insulated Panels: Sustainable Design Incorporating Impact on Indoor Air Quality which gives the result of actual testing of emissions from SIPs. Using small-scale chambers, emissions were measured over a period of four months. The measured emission factors were then used to estimate the concentrations of VOCs in SIP-based manufactured houses. The testing found formaldehyde, toluene, styrene, and other volatile toxic chemicals to be present.
In my new book Really Green, I talk about how products have many facets, and can be beneficial in one aspect, while harmful in another. This is just such a case. Yes, using SIPs improves the energy efficiency of a home, but it also adds toxic chemicals to indoor air and is made from non-renewable crude oil and will not bio-degrade. So I wouldn’t consider this to be an overall good green choice.
This is a good example of why I wrote Really Green. There are so many products now being promoted as “green,” yet those who are promoting them aren’t looking at the whole picture. This is exactly why we as consumers need to know for ourselves how to evaluate products for being green so we can decide for ourselves if a product is green in the ways that matter to us.
