GreenYour.com

When you choose recycled insulation you’re not only taking steps to save heating and cooling energy in your home, you’re also decreasing the amount of solid waste going to the landfill. The insulation industry uses many recycled materials, so you have choices—from the fluffy pink stuff (fiberglass) to recycled denim jeans!

Find it! Recycled insulating materials

Before you buy

If you are looking to avoid insulation products that off-gas volatile organic compounds (VOCs), which contribute to indoor air pollution, then look for GREENGUARD certified products. The GREENGUARD Environmental Institute has a third-party certification program to test low emitting interior building materials, furnishings, and finish systems.

Choosing recycled insulating materials helps you go green because…

• It diverts waste materials, such as glass, denim jeans, and blast furnace slag, from the solid waste disposal stream and saves landfill space.
• It reduces the amount of energy needed—and pollution emitted—during the manufacturing process because less energy is needed to make insulation from recycled content products than from using raw materials alone.[1]

The majority of residential insulation sales in the US—80 to 90 percent—are for fiberglass and cellulose products.[2] Both use recycled materials. In fact, most insulation products have some recycled content.

Fiberglass

Fiberglass batting is made by melting minerals, and sand or recycled glass. Between 1992 and 2000, more than 8 billion pounds of pre- and post-consumer glass containers were used instead of sand. Most fiberglass contains 30 to 40 percent recycled content.[3] The amount of recycled glass used for insulation in the US increased 18 percent in 2005.

On the negative side, the manufacture of fiberglass is energy intensive because the materials need to be melted before they are spun into strands. The fiberglass and slag wool insulation industries combined use nearly 33 trillion Btu (British thermal unit) of energy annually.[4] Also, the fiberglass strands are held together with binders traditionally made from formaldehyde, a VOC that can off-gas into the air. Some manufacturers are now producing fiberglass insulation without this cancer-causing chemical.[5] See “Before you buy” above for information on low-VOC certified products.

Cellulose

Cellulose insulation is made from 80 to 85 percent recycled newspaper. In 2004, 773,000 tons of cellulose insulation was produced.[6] To meet fire ratings set by building codes, cellulose is treated with fire retardant chemicals. Borates are the preferred chemical additive as they are considered non-toxic and are derived from the mineral boron.[7][8]

Because recycled newsprint contains printing inks, there is a concern this insulation can out-gas low levels of formaldehyde into a home. Therefore, it is suggested that environmentally sensitive people install a barrier between the insulation and the wall.[5]

Rockwool

Rockwool is recycled steel slag, a byproduct of steel manufacturing that would normally go to a landfill. More than 75 percent-recycled slag is used along with about 25 percent basalt rock.[7]

Recycled Cotton

Cotton insulation is made with mill waste, as well as low grade and recycled cotton. Like cellulose, it is treated with non-toxic borates as fire retardants.[7] It is often promoted as recycled denim insulation because denim jean manufacturing plants are one source for recycled cotton, as well as “denim drives.” Cotton Inc. organizes denim drives on college campuses and other communities to collect old jeans and other cotton clothing. In 2006 the denim drives collected 14,566 pieces of denim.[9]

Related health issues

• Some insulation, as noted above, may contain VOCs, chemicals which become a gas at room temperature and may be released into the air through a process commonly called off-gassing. Formaldehyde, classified by the US Environmental Protection Agency (EPA) as a probable human carcinogen, is one such VOC used in several types of insulation as a bonding agent or solvent.[10][11]

• Formaldehyde can still be found in varieties of fiberglass and rockwool insulation, and may also off-gas from the newsprint ink residue found in cellulose insulation.[12] Although the US Consumer Product Safety Commission (CPSC) does not note any specific warnings about the formaldehyde content in today's fiberglass insulation (and makes no mention whatsoever of formaldehyde content in rockwool or cellulose), 10-20 percent of the population may have hyper-reactive airways making them susceptible to formaldehyde-induced irritation in their eyes and respiratory tracts at minimal concentration levels.[10] Fiberglass fibers may cause similar irritation symptoms when touched or inhaled, but—despite years of controversy—the American Lung Association does not currently classify the material itself as a cancer risk.[13]

Glossary

• boron: Boron occurs naturally as borates in oceans, sedimentary rocks, coal, shale, and some soils. It is an essential micro-nutrient in the soil and is found in human food and water supplies. The mean daily intake of boron in the diet is about 1.2 mg. The few studies that have been done on human health do not show any long-term effects.[14] However, the EPA recommends more testing.[15]
• Btu (British thermal unit): A unit of energy used universally in the heating and cooling industries. It is defined as the unit of heat required to raise 1 pound of water by 1°F.
• formaldehyde: A flammable reactive gas belonging to the VOC family of chemicals. It is widely used in personal care products, building materials, insulation, and home furnishings. Ingestion of the chemical can cause severe physical reactions, including coma, internal bleeding, and death.[16] The US Department of Health and Human Services considers it a probable human carcinogen.[17]
• volatile organic compounds (VOCs): Gases released by a wide variety of products, including household cleansers, furniture, and dry-cleaned clothing.[18] VOCs can cause several health concerns, ranging from headaches and respiratory inflammation to central nervous system problems.[18] VOCs are also considered a possible carcinogen.[18]

External Links

• eHow - How to recycle jeans for insulation Organize your own denim drive!
• The Green Guide - Fiberglass Insulation Debate