On Green Insulation …

The northern wing is now gutted and almost ready for insulation. My quandary is what insulation to choose. Recycled blue jeans seems promising, but we live in the woods and local rodents would summon all their cousins to sleep in this deluxe bedding. Jeff at Conway Lumber in Provincetown tells me the insulation has been treated to make it less attractive to varmints, but do we want insulation with chemicals in it? We used Atlas Energy Guard sheathing in the cottage bathroom renovation. So far the company has been answering without a direct answer as to its composition. (MDI, Polyols, combined with blowing agent cyclpentane and some of the ingredients are reclaimed side streams from other manufacturing operations that would otherwise end up in landfills). There is no doubt that Energy Shield is an efficient product, but this is the first time I thought about composition. Sounds like chemicals to me. For our northern wing renovation, the contractor wanted to use Sealection 500. Online reviews are favorable, but again, it is petro-chemical based. I read the brochure about HeatLok Soy, a new closed-cell insulation touted as a great green choice, and learned there is a small amount of soy and a large amount of recycled plastic bottles. The percentage: 27% soy. Everyone seems to be applauding these new green options, but what will they mean for the environment down the road? Does anyone remember how asbestos was hailed as superior in the 50s? Can an envelope of recycled plastic be a healthy option? Once the outgassing stops, is the danger over? What about toxic fumes in case of fire? What happens if I make the wrong choice and it is necessary to remove the product? I have searched the Internet but have not found answers so far. Jeff at Conway Lumber recently created his own LEED-certified house. He commiserated over the phone when I explained I had hoped for bio-based products. He had the same hope, but unfortunately it is harder to find a bio-based distributor down on the Cape, so he used Icynene, an open-cell foam. There is also Air-Krete, which is foam without plastics, made from concrete. The Wellfleet Bay Sanctuary used recycled blown-in newspaper in their walls. The Seashore is using blue-jeans for their Race Point facility. I called up a local carpenter friend and he still uses fiberglass since most clients do not want to spend extra money for insulation. Now that heat has become so expensive, that situation may change. Our carpenters are almost ready for insulation. Since this photo, they have added the roof. How little information there is on the Web! I visited the site created by the Wellfleet Bay Wildlife Sanctuary last year to document construction of its new green building, which was inspiring but not conclusive for the choice here at Chez Sven. As we ponder what insulation to choose, here is the only site I found which offers an impartial review of the different options.