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Community and Q&A

Boral/TruExterior is made from fly ash isnt that concerning

user-1112710372 | Posted in General Questions on

I am debating between Boral/Tru exterior versus Hardie.  The Boral actually specs better for what i want to do but I am very concerned about Fly ash which its made from being a known toxic material then cutting it into a dust.  This would be dangerous for the crew and also my kids playing in the yard afterwards.  Guaranteed no one is going to follow all the safety guidelines when cutting. I am curious what others think about this issue?

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  1. Expert Member
    Michael Maines | | #1

    You're worried about fly ash but not fine silica dust from the Hardie or the fine plastic particles from the Boral? None of it is safe to breathe, and the plastic should not be expelled into the environment. We are dealing with PFAS ("forever chemical") contamination in water and soil here in Maine, which causes or contributes to major health problems. At least the fly ash and silica are naturally-formed materials.

  2. Expert Member

    User ...604,

    There are really two parts to this.

    Could enough fly ash accumulates near where the work was done to pose an ongoing environmental risk? That I don't know.

    The second - whether there is a risk to working with them - is much more straightforward. There are many building materials and tasks - from using fiberglass batts to high VOC finishes, or working at unsafe heights - which require the installers to take steps to minimize the risks. If their work practices don't do that it's on them.

  3. Expert Member
    BILL WICHERS | | #3

    The biggest risk is from breathing the dust, and as Michael mentioned, the silica dust produced by cutting fiber cement products like Hardie plank/board are dangerous too. Outside of breathing the dust, there is little to worry about with any of these products. Note that you can minimize dust production by using one of the purpose built guillotine-like blade devices that chop the board like a shear instead of cutting it with a sawblade. Shearing produces almost no dust and is much safer health wise as a result.


    1. Expert Member
      MALCOLM TAYLOR | | #4


      I've got one of these. I works great on cement based siding and laminate flooring.

      1. Expert Member
        BILL WICHERS | | #5

        Yeah, that's what I was thinking of. MUCH less dust with one of those, and a cleaner cut too!


  4. user-1112710372 | | #6

    Thanks all. It’s easy to get obsessed on one detail and loose sight of the forest.

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