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Community and Q&A

Insulation for metal horse barn

SkywardFarm | Posted in Green Products and Materials on

I “inherited” an MD BarnMaster metal barn built in 1999. I’d like to insulate and Bayseal Closed Cell Foam has been recommended by several companies.

There are air gaps throughout the barn, mostly where the roof meets the frame, where moisture gets in. Some have been filled with bat insulation or spray foam (out of a can bought at Home Depot).

I have 2 questions:

1) Would prep work to fill those gaps be needed BEFORE the Spray foam is applied? My concern is the moisture would “eat away” at the spray foam over time and rain down toxic dust on my livestock,.

2) I have read about the off gassing/poorly applied Spray Foam issue on this site and would like to know IF one had a badly done Spray Foam job what the procedure a company might take to remediate it? Would the building need to be condemned?

Thank you for any/all answers. This is a great resource – thank you!

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  1. Expert Member
    Dana Dorsett | | #1

    Closed cell foam is even used as a roofing material- moisture won't eat away the spray foam, but UV light can damage it. With closed cell foam roofing they paint it with a UV blocking paint, or cover it with stone ballast, etc.

    To make more detailed recommendations it helps to know...

    Why are you insulating the barn?

    What R-value are you shooting for?

    As a general rule closed cell foam is one of the least green and most expensive ways to insulate a building. Depending on your goals there are likely to be cheaper& greener ways to get there.

    1. SkywardFarm | | #3

      Dana - Thanks for your response to my questions.

      I want to insulate for 2 reasons:

      1) Metal barns are cold in the winter, hot in the summer and I’d like to regulate the temperature. Even 10 degrees makes a difference.

      2) Metal roofs are loud when rain and hail hit. I’d like to create a sound barrier so if I am treating a large animal they are not in fight or flight mode!

      As for R value, I am not sure given it is a barn. Given my reasons for insulating, could you make a recommendation?

      Thank you!

      1. Expert Member
        Dana Dorsett | | #4

        With only the livestock for a heat source insulating the barn won't make an enormous difference in winter unless you also air-seal it and use well metered active ventilation.

        Open cell foam uses less than half the polymer per R of closed cell foam, and uses water as the blowing agent rather than climate damaging HFCs. 4" of open cell foam (R15-ish) uses half the amount of 2" of closed cell foam (R12-R14), and costs less than a mere 1" of more benign HFO blown foams.

        In summer a layer of perforated aluminized fabric type radiant barrier mounted to the underside of the rafters can make a 10F or greater reduction in peak & average temperatures, but does very little in winter. Even if the roof is foamed (with 2" of closed cell or 4" of open cell) the RB can still provide some additional relief during the hottest sunniest days if there is at least an inch of air between the foam and radiant barrier. It's not going to make any noticeable difference on walls, only roofs.

  2. GBA Editor
    Brian Pontolilo | | #2

    Hi Skyward Farm.

    Not only do you want to protect the spray foam from UV light, but you also don't want it to make its way through the gaps in the building and make a mess. It is not easy stuff to clean up.

    We've heard plenty of stories of spray foam jobs gone bad and installers not taking responsibility for the problems. But if you can find a reputable spray foam contractor, neither should be a problem.

    As Dana pointed out, closed cell spray foam is expensive and not particularly green. Maybe there are other options. It will be helpful for GBA members to know more specifically what you are trying to achieve (a particular R-value, air sealing? Are your planning to heat the space?)

    In the meantime, this article may be helpful: How to Insulate a Pole Barn

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