Product Brochure
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What happens next? Mold and Building Product Deterioration
Take this a step further. Say you have exterior insulation on your structure and you use closed cell foam with a perm
rating of .8 at 2.5" thickness for your interior insulation. You think you are doing the right thing. You have 3.5" of spray
foam to meet code, plus you have added the exterior insulation. Well, you have a well-insulated structure but closed
cell foam is not smart. It blocks moisture coming and going. Then, with poly-iso or XPS on the exterior, you now have
a moisture sandwich again. Remember, any perm rating below 1.0 is a vapor retarder. In this instance, it might be
better to use a smart vapor retarder plus fiberglass and your exterior insulation (or go thicker on the spray foam and
eliminate the exterior insulation).
The Value of Energy-Efcient Buildings
It has taken some time, but the building industry is finally starting to recognize the value of building energy-efficient
to quantify and monetize the value of incorporating energy-efficient features into a home. RESNET and the Appraisal
Institute have made significant strides in developing tools and methods for quantifying the value of these homes.
Some markets, like the Pacific Northwest, have seen these homes stay on the market for 24% less time and at
a much higher premium than standard homes in the same market (“An Introduction to Green Homes,” Appraisal
Institute). Today’s homeowners are clearly interested in investing in a home that will better address air and moisture
flow to ensure their comfort.