EcoCell cellulose mats in basement?
Hello. My name is Tom and I’m currently building a new construction home in SE Michigan, zone 5. I have hired an energy consultant who has run the energy certs for the home and is helping me along the way with some details.
The home is a small ranch, 1377 sq foot.
So far all of the suggestions stated by the energy consultant correlate with everything I have read from your book / website.
He has recommended a product called ‘eco cell’ to insulate the basement walls. It is essentially a 4×8 mat made from cellulose that adheres to the basement wall. It can be left exposed as we do not plan on finishing the basement.
http://cmsgreen.com/sites/default/files/ecocell_brochure.pdf
Do you have any experience with this product? Would the main concern be air condensing on the concrete basement walls? I will post an attachment to the product
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I have no experience with the product, but my main concern would be excessive moisture accumulation on the cold side of the cellulose and moisture wicking. Concrete isn't harmed by moisture, but the performance of cellulose takes a serious hit when it's too damp.
In a basement application you're dealing with both wintertime moisture accumulation when the concrete is below ~40F, and ground moisture wicking into the concrete and then into the cellulose. An air impermable and vapor retardent insulation layer sufficient for dew point control on the cellulose-R of the above-grade portion makes more sense than putting fiber insulation in direct contact with the concrete.
I have a friend who used it and to my surprise, he never reported a moisture problem. But he eventually remodeled and switched to closed cell foam.
Prudent best practices and what works can often be two very different things. Insulators here typically attach plastic encased rolls of fiberglass batt to crawlspace walls. Against all odds I've never encountered moisture or mold in these assemblies. It makes it quite difficult to steer clients to the ones building science generally recommend.
Tom,
One other point: Building codes require a minimum of R-15 basement wall insulation in your climate zone. But this product (EcoCell blankets or mats) comes in two thicknesses: either R-6 or R-10. So even if you choose their thickest product, it still provides a lower R-value than minimum code requirements.