Insulation materials can benefit the environment by hugely reducing our carbon footprint.
Insulation is key to reduce carbon emissions coming from buildings. We should not forget that - from an energy savings and environmental standpoint - energy conservation is at least as important as energy generation, and that the building sector is the major responsible for energy consumption and directly or indirectly the greatest CO2 emitter. In this sense, insulation is as important as solar photovoltaics, wind and other green sources of energy.
Unfortunately, blowing agents in products like polystyrene can offset part of the benefits they provide.
Consider the amount of recycled materials in insulation products. It may be important to help prevent the depletion of natural resources.
Green insulation options
Fiberglass green insulation products
When choosing fiberglass insulation, consider formaldehyde-free fiberglass with high recycled content (some manufacturers are offering fiberglass insulation with up to 70% of recycled glass).Modern insulation materials do not pose any known significant danger to our health, if conveniently isolated from our living space. But they do still pose some small risks.
Fiberglass is skin, eye and throat irritant, while cellulose can be respiratory-irritant, due to the fire-retardant chemical treatments used in its production.
But, on the other hand, they aren't dangerous once installed.
Concerns about fiberglass as a cause of lung cancer do not seem founded (see American Lung Association), though some people still state otherwise.
For information on these issues, see:
Cellulose and Slag/Mineral Wool insulation
Consider cellulose insulation made from recycled newsprint. Slag wool insulation can contain up to 90% of recycled content, but on average this value is approximately 70%.
For a list of slag and mineral wool insulation manufacturers, see:
For cellulose issues, or to find out manufacturers or contractors, see: CIMA
Foam insulation products are petroleum based, with little recycled content and very high levels of embodied energy - which isn't good for the environment. But polyicynene, at the core of polyurethane and other foams, is a non-ozone-depleting chemical, environmentally-benign.
You may consider polyurethane made with soybean oil, sugar cane and corn.
Polystyrene plastic elements (benzene and styrene especially) are very negative for the environmente, and should be avoided as much as possible. See: Polystyrene insulation Asbestos and toxic products
Some types of vermiculite and products such as urea-formaldehyde, used as insulation materials between the 1920s and 1980s, are now banned. They were toxic products or a source of asbestos, and their removal in old buildings should be carefully addressed. See, on the issue of asbestos removal, in different countries: USA and Canada, UK, New Zealand, Australia.
Other Green Foams
See, for instance: Icynene Insulation
Always choose formaldehyde-free insulation batts; recycled cotton insulation batts are between the most greener insulation options. See: GreenBuilding.org