Design Architecture What's the Greenest Insulation? It's Getting Harder to Decide Every Day By Lloyd Alter Design Editor University of Toronto Lloyd Alter is Design Editor for Treehugger and teaches Sustainable Design at Ryerson University in Toronto. our editorial process Facebook Facebook Twitter Twitter Lloyd Alter Updated October 11, 2018 Migrated Image / Screen shot from Youtube video Share Twitter Pinterest Email Design Tiny Homes Architecture Interior Design Green Design Urban Design What's wrong with this picture? It is in a video promoting Ultra-touch denim insulation, showing an installer pushing a full-size batt into an irregular cavity. Either the insulation isn't going to work because it is compressed or it is going to pop the drywall right off the wall. The installer also isn't wearing a mask, even though the company's material safety data sheet recommends an OSHA approved air mask. (the stuff is vermin-proofed with borax). It is just one of the problems that Tristan Roberts of BuildingGreen finds with the product. Even though I gotseriously schooled by an Ultratouch distributor at a home show last year, I still have problems with batt insulation; it is rarely properly installed around electric wires and other irregularities and does not seal as well as sprays. Others are also complaining that using old jeans means that it is contaminated with fabric softeners; one commenter to Tristan's post complained: Post consumer recycled jeans are not good for the chemically sensitive, for whom this is a prime product. Most of those jeans will have been washed multiple times in scented detergent and dried in driers with bounce fabric softener. You can *NEVER* get that stuff out. So much for bonded logic. Is Sprayed Polyurethane Insulation Safe? I was particularly fond of polyurethane insulations, whether open celled like Icynene or soy-based, or even the regular stuff, but now there are increasing concerns about their safety because of the outgassing of isocyanates. There are also concerns about the ability deconstruct or recycle down the road, because it sticks to everything. To top it all off, it is toxic when it burns; that's why I think if you use it,you should also install sprinklers. Migrated Image Polystyrene Insulation Doesn't Belong in Green Building Then of course there is the issue of toxic fire retardants in polystyrene. Some think it is good enough to getcradle to cradle silver; others, like Arlene Blum say "It is shocking that a product containing a persistent organic pollutant such as HBCD can be considered green." (others complain more about the fact that it is a petrochemical product). Fiberglass: Is Pink Really Green? There are so many issues with fiberglass it is hard to know where to start; it doesn't work very well, it may be dangerous (see More Chemicals Added To HHS List Of Known or Suspected Carcinogens) and some think it should be bannedbecause it is installed so badly so often. We have not written a lot about sprayed cellulose, but will be doing more; it is made from recycled content, has the lowest energy input of any insulation, seals well and I have seen few complaints, although people with multiple chemical sensitivities worry about the inks. Air Krete: Green Insulation from Cement Perhaps Al Gore got it right; he insulated his house with AirKrete, a foamed magnesium oxide cement that is fireproof, has no toxic chemicals, and is mold, bug and water resistant.