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A question about Guardian UltraFit DS blown-in fiberglass insulation

udLcB6AcF8 | Posted in General Questions on

A insulation contractor gave me the option of a wet spray blown-in fiberglass product. Made by Guardian, UltraFit DS appears to be applied like wet spray cellulose. Any insight, pros/cons would be appreciated.

Home located in North Central Washington State. Climate zone 5.


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  1. Xg7thss8Js | | #1

    I don't have direct experience with this product. Be aware of trapping construction moisture inside of walls, though. All wet-applied materials must be allowed to dry fully or the risk of mold increases significantly (even in Climate Zone 5). This may mean waiting on the drywall until the insulation has completely dried out. With fiberglass, I'd assume fans and heaters could be used to accelerate the process, but you should check with the manufacturer because some binding agents release flammable chemicals when they dry/cure.

    The problem of trapping moisture inside walls gets worse as the building enclosure gets better, ironically - due to the reduced drying potential. There just isn't enough heat flow nor sufficient infiltration to help the moisture migrate out to air.

  2. GBA Editor
    Martin Holladay | | #2

    Hese's a link to information from the manufacturer: Guardian UltraFit DS insulation.

  3. GBA Editor
    Martin Holladay | | #3

    Blown-in fiberglass can perform very well -- usually much better than fiberglass batts. It's up to you to decide which insulation type you prefer.

    Either cellulose or blown-in fiberglass is a perfectly reasonable wall insulation. As with any insulation material, the skill of the installer determines the quality of the finished product.

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