Toxicity of Foamular NGX and Purple Board
We’re finishing our basement and plan to use Rigid Board insulation, metal studs and Purple Board .
I’m sensitive to chemicals/toxins, so want to make sure the products are safe.
Are Owens Corning FOAMULAR NGX & Purple Board Drywall safe? Thanks in advance!
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From what I’ve read, FOAMULAR products are certified to meet indoor air quality standards under the GREENGUARD Standard for Low-Emitting Products, and the GREENGUARD for Children & SchoolsSM product certification programs. Similarly, PURPLE gypsum board is GREENGUARD GOLD–certified for indoor air quality. That suggests to me that you shouldn’t experience any sensitivities.
Wonderful! Thanks so much, Kiley Jacques!
Foamular is made of polystyrene, the same stuff as the styrofoam coffee cups. It's a very stable material that holds up well, and isn't prone to offgassing. You might have a small amount of "new foam smell" at install time, but it should be pretty minimal and will dissipate quickly -- similar to "new car smell". I personally hardly notice a smell with this material except when cutting it with my hot wire cutter.
I don't have much expierience with the purple drywall so can't comment on that.
In the evaluations I've seen of the potential health impacts of the fire retardant chemicals in XPS and EPS, the conclusion is usually that the concerns are pretty neglible in the use phase, and the only concerns are in the manufacturing process ... or in hot-wire cutting. So I would recommend that Masb cut it or have it cut with a knife rather than a hot wire.
Cutting options include a segmented box cutter knife fully extended, an electric carving knife, or a knife-edge bandsaw blade. I've personally tried the first and the last and was amazed at how well the band knife works. The cuts you can make are, unfortunately, limited by the throat depth of the saw, so you can cut about a foot off your 4x8 board but you can't cut it in half.
As best as I can tell, purple drywall is essentially the same as other brands' "MMR" (moisture and mold resistant) drywall. The mold resistance is from thiabendazol, azoxystrobin and fludioxonil fungicides. At least some of those are also used on crops, so given that you aren't going to be eating your drywall, it's safer to have it in drywall than on crops. And the Greenguard certification indicates that it's not going to outgas--it will stay in the paper.
The other option is to avoid those and use fiberglass composite skins, which allows mold resistance by avoiding paper. Depending on your sensitivities, that might or might not be better.
Getting into more exotic options, there's MgO board or monolithic paperless drywall such as Fibrock from USG. Fibrock is greenguard certified, but I'm not clear on whether it has fungicides in it.