Choosing Sustainable and Green Building Insulation

When we think of green and sustainable buildings, we often think of the things we can see and notice such as windows, paint, and countertops. It’s not often we think about the things we don’t see. Insulation is one of those things.

Insulation was first used for its thermal properties and later for acoustical purposes. It’s found inside our walls and attic, so does it really matter if it’s green? The answer is ‘yes’!

We spend a lot of time indoors so what’s in our walls is important, especially if it has an impact on the air we breathe. Many of the first materials used for insulation were found to emit fumes, contain materials that are dangerous (such as asbestos) and absorb moisture causing mold and mildew.

With a wide variety of green insulations available on the market, how do you weed through the “greenwashing” to find truly sustainable products?

Green and Sustainable Insulation Checklist
All insulation materials have properties that add or detract from the overall green or sustainable nature of the product.  When you identify insulation that you want to use, you will need to assess it for its green and sustainable factors. Here is a checklist of factors and properties to be on the lookout for:

- Thermal Properties – Thermal performance is one of the important factors for insulation. Does the product keep the building warmer in the winter and cooler in the summer? Does it eliminate drafts and cut down on air infiltration? Check the product’s density; it should address these concerns.

- Acoustical Properties – Similar to thermal performance, this is another important factor for insulation, especially in high-density buildings. Note the Noise Reduction Coefficient (NRC) and the Sound Transmission Class (STC) of the product to ensure it will work for the building. The NRC number tells you what percentage of noise the material will absorb (for example 0.70 means the product will absorb 70 percent of noise). The higher the STC rating the more noise the product can block from going through walls.

- Air Quality – As mentioned earlier in this article, many of the earlier insulation materials were found to emit dangerous components into the air. To be sustainable, the insulation product shouldn’t diminish air quality in the building. Do some research on the material and make sure it doesn’t emit harmful chemicals or contains irritants that can impact respiratory health. Also be sure to verify that it doesn’t contain volatile organic compounds (VOC), which are consistently more concentrated indoors than outdoors -- up to ten times higher according to the EPA.

- Recycled Content – Considering that manufacturers have many raw material sources available, it is more sustainable to choose products produced from recycled materials. This includes pre-consumer materials (such as scraps from the manufacturing process of another product) and post-consumer materials (such as newspapers or denim).

- Renewable Sources - Along the same lines as recycled content is renewable sources. Rapidly renewable sources such as cellulose or cotton fiber are more sustainable. Do your homework. There are materials out there that mimic truly sustainable products but are really made from non-renewable sources such as petroleum-based foam or plastic. Other newly labeled sustainable products may address one concern, but leave other potential problems untouched.

- Waste Reduction – Don’t you just hate it when you finish a project and have a large amount of material left over? This produces waste, and with various sizes required for installation, insulating projects can generate some scrap material.  Whatever waste is created should be able to be used somewhere else in the project.

- Installation Requirements – For your health and safety, choose a product that is safe to touch and easy to work with. Sometimes packaging will show a person handling the product but the warning label says to wear a respirator, gloves and protective clothing, so don’t be fooled.

- Energy Performance - Most products are tested for heat transfer under certain conditions and will contain a rating on the packaging. Be sure that the tested conditions are similar to those of the building the material will be used in.

- Manufacturing Process – It’s not always enough that the product is made out of green or sustainable materials. The manufacturing process used to produce the product contributes greatly to the embodied energy within the finished goods. Has the manufacturer taken steps to reduce the energy used to produce the product, utilized recycled or recyclable packaging, and developed efficient delivery methods? These are good things to look into as well.

Reviewing all of these factors and properties can help you find truly green and sustainable products. If you aren’t sure about a product, contact the manufacturer with your questions and ask for proof where necessary.

Denim Insulation
One type of insulation that addresses all the factors and properties listed in the checklist is denim insulation. Recently featured on a segment about winterizing your home on Good Morning American, denim insulation is sustainable for a number of reasons.

The primary raw material source is post-consumer recycled denim. This waste material is diverted from landfills -- approximately 300 tons monthly. The denim is given another life-cycle by being transformed into cotton batt insulation.

The recycled denim is comprised of cotton fibers, which are a rapidly renewable resource and have a rapid growth cycle. Denim insulation is treated with a borate-based solution for fire retardancy, mold/mildew growth, and pest resistance. This treatment is an EPA registered material and has a lower toxicity than average table salt. Denim insulation also contains no formaldehyde.

Denim insulation products have been tested and show no VOCs within the product or off-gassing concerns. Other than a standard dust mask, no special clothing is required for the installation due to the environmentally friendly materials used to manufacture the product.

The manufacturing process uses minimal amounts of energy in comparison to traditional insulating products. In addition, all scrap and manufacturing trim are re-introduced into the raw material supply creating a virtually zero waste process.

Denim insulation can earn up to 12 LEED™ credits for a project. The insulation also offers maximum thermal performance and superior soundproofing (30 to 50 percent increase in acoustical performance).

Conclusion
Taking the time to learn about insulation materials is worth the effort. Once the insulation goes into your walls, you won’t see or think about it. But knowing that is can impact health, air quality, and the environment should be enough to make you take the time to choose the right material.

No doubt that going with a sustainable product will cost you more. That is true for almost any green material. Making the decision to go green inside your walls is the right choice. After all, we are what we breathe!

About the Author
Sean Desmond is the Sales/Marketing Manager for Bonded Logic. He has been with the company for six years and is a strong believer in sustainability, particularly when it comes to insulation. Sean is very proud of the growth of the green building industry over the past decade, and plans to be a part of the future of sustainable building for many years to come. For more information on Bonded Logic and its products visit www.BondedLogic.com.