VOCs and SVOCs: What do we know?
So a video published today discusses a topic I’ve been thinking about for a while. I’m going to be building our new house soon and the topic of indoor air quality and VOCs is something I’ve had on my mind but have yet to research fully.
In this new video, Matt Risinger and Corbett Lunsford discuss VOCs and SVOCs:
I’ve been thinking about oil based paints for a while now, and lo-and-behold, the topic comes up in this video where two building experts are discussing their qualities and perhaps suggesting that oil based paints are not as bad as we were led to believe, and that “low VOC” paints might be worse than we think.
I know there’s a TON of expertise and knowledge on this site, and I’m wondering what the experts here have to say? Perhaps you know of studies that contradict popular opinions? I’m looking for the truth about ALL common building materials, not just paints (though paints are a big one).
So what say you? If you were building or renovating your own homes what paints would you use and why? What building materials would you lean towards and which would you banish from the build? Do you have any studies to reference that reinforce your views? Thanks!
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Replies
No expert, but I expect that some VOCs are harmless and others are quite dangerous. Consider letting your house sit for awhile before moving in and then running higher levels of ventilation. Think less about initial VOC content and more about residual VOC content.
Lance,
My reactions:
1. I agree with Corbett Lunsford and Matt Risinger that it makes sense to avoid vinyl flooring. I made the same recommendation in my article, "Vinyl Windows and Vinyl Siding."
2. I agree with Corbett Lunsford and Matt Risinger that it makes sense to avoid plug-in air fresheners and aerosol air fresheners. I made the same recommendation in my article, "All About Indoor Air Quality."
3. The research discussed by Corbett Lunsford is being funded by the Sloan Foundation. Research is good, but this research is ongoing, and we should wait for the final report before we jump to conclusions. The Sloan Foundation has already spent $50 million on a project called "Microbiology of the Built Environment," with the expectation that the study would identify microorganisms responsible for human health problems. In fact, the research found that data did not bear out the expectations of the researchers.
For more information on the Sloan Foundation research, see my article, "Indoor Microbes and Human Health." In that article, I wrote:
"Teams of biologists supported by the foundation have conducted research that included indoor sampling for microbes and lots of DNA sequencing. What have these researchers learned? ....
"For the conference attendees, the most striking takeaway from this presentation was the fact that experts don’t really know what a healthy house is. Providing an overview of years of research supported by the Alfred P. Sloan Foundation, Hal Levin said, ‘What are the practical implications of this recent work? Do we know enough to make buildings healthier? Not yet. … We don’t know as much as I had hoped we’d learn about microbes and health.’ ...
"Siegel said, ‘Why do we care about mold or microorganisms? Well, mold smells and looks ugly. But what is the connection between mold and health? We know from several studies that moisture damage to buildings has a negative health effect on occupants. Moisture is a problem from a health perspective. But the role of microorganisms in these health effects is not clear. Microorganisms are often protective of health, not harmful.
“ ‘We don’t know why moisture is a problem, we just know that it is. It might be chemical. Microbial diversity is good, and water leaks increase microbial diversity. So this is a paradox.’”
In short: Research conclusions are hard to predict before a study is over.
Good news about oil based paints. In many ways they are superior to latex/acrylic. They form thinner films and can be sanded in the future to blend in repairs. However, they are class I vapor barriers so they should not be used on the inside of outside walls or poorly ventilated exterior cladding.
Doug Higden
Jon R, surely solid advice, will do!
Martin, thanks for the info. It will be interesting to see the results of this latest round of testing, for sure. I'll be doing a little digging of my own to see what I come up with as well.
Thrifttrust, thanks for the info, I didn't know oil paints were vapor retarders, I'll definitely avoid use on walls. I was thinking more along the lines of trim and hardware, railings/balusters, doors, places where the majority of wear and tear takes place. Having a more durable finish on baseboards is something I'm definitely up for, especially if we skip using 1/4 round along the bottom.
Doug Higden / ThriftTrust,
You wrote that oil-based paints are "Class I vapor barriers."
You're wrong. A Class I vapor retarder has a vapor permeance of 0.1 perm or less.
Two coats of oil-based paint on plaster have a vapor permeance of 1.59 to 2.99. Obviously, one coat of oil-based paint would have an even higher vapor permeance.
Three coats of oil-based paint on wood siding have a vapor permeance of 0.3 to 0.99 perms.
So one or two coats of oil-based paint is a Class III vapor retarder.
Three coats of oil-based paint is a Class II vapor retarder.
Great info, Martin! So would oil based paint still not be recommended for use on the interior side of exterior walls?
Lance,
Q. "Would oil based paint still not be recommended for use on the interior side of exterior walls?"
A. The answer has nothing to do with vapor permeance. (Installing a vapor retarder on the interior side of exterior walls is normal in cold climates -- in fact, it's a code requirement.)
Most people avoid using oil-based paints because of VOC concerns, concerns about air pollution (especially in California, where the use of these paints is restricted), and because cleanup is difficult.
Thanks Martin. It's the VOC concerns I'm most focused on. I'm wondering if the suspected high short term low long term VOC profile of Oil based paints is any better or worse than the higher long term SVOC output of today's water based paints. Let's see where the studies lead us.
Lance,
I used potassium silicate paint on my last home because it had good performance characteristics and zero VOCs. The manufacturer told me this product is increasingly popular with painters who have developed chemical sensitivities after using conventional latex paints.