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Community and Q&A

Borate only blown cellulose

stk | Posted in Green Products and Materials on

Does anyone know of a good quality borate-only cellulose product available in the Seattle, WA area? The contractor gave me an MSDS for a product called Isolite Cellulose (made in Spokane, WA) which uses sodium polyborate. How does this compare to boric acid, which I see some other products using? Are all brands of borate-only blown cellulose of similar quality? This is for attic insulation R-49. Thanks!

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  1. stk | | #1

    The Isolite brand product is made by Thermoguard Insulation Company in Spokane, WA. It uses approx. 25% polyborate by weight. No other types of boric or borate used, just the polyborate. The contractor normally uses Greenfiber (with sulfate). Contractor did not propose using one of the Greenfiber products without sulfate. I am concerned that Thermoguard/Isolite is a lesser quality "Brand X."

  2. Jon_R | | #2

    Everything I've seen indicates that boric acid and sodium borate are very similar.

  3. charlie_sullivan | | #3

    I think the standard recommendation is that any kind of borate is fine, and that ammonium sulfate is the one that is undesirable. But perhaps someone who knows more chemistry will help us understand better.

  4. stk | | #4

    I get the impression that there are many cellulose companies that sell primarily to contractors. so don't focus on "brand" like National Fiber, US Green Fiber, etc. I am looking for a borate-only product, which I learned about on this website. Now the question is if all non-borate cellulose is about the same (i.e. a commodity product) or if there actually are quality differences between manufacturers. Thermoguard is owned by Service Partners, which is a national building products firm. Says they have been in business in Spokane since 1951.

  5. stk | | #5

    Sorry, I meant borate-only, not "non-borate."

  6. finePNW | | #6

    It seems Greenfiber Sanctuary (and not its Sound Barrier product) is ammonium sulfate free -- or at least it's not listed in the SDS. Instead, perhaps, it seems they may use Calcium Sulfate Dihydrate. Anyone know a) if this is correct and b) if this poses the same corrosion concerns?

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