Types of Green Insulation

The focus on having an energy efficient home is not new, but is green insulation the way to go to help reduce your carbon footprint? Some types of green insulation are good for the environment in terms of using recycled materials. Others have a higher R-value to help make your home more energy efficient and reduce your carbon footprint. Learn more about the popular types of green insulation homeowners are turning to.


Icynene is a spray foam insulation that is non-toxic making it safe and a green insulation option. Of green insulation options, it has the highest R-value at R-7 per inch, making it an effective insulator. Spray foam insulation is a versatile insulation material that can be used in a variety of applications including walls, roofs and crawlspaces. This type of insulation is also used for air sealing by filling gaps and cracks to prevent air leakage thus improving indoor air quality and reducing energy costs.

Closed cell spray foam insulation is a durable and long-lasting material that can withstand moisture and humidity making it resistant to mold and mildew. It also helps keep pests away since it covers small holes and gaps that may be throughout your home. Icynene spray foam is ideal for keeping your home comfortable due to its high R-value and air sealing capabilities. Unfortunately, it does have a higher carbon footprint compared to other forms of insulation since it is a petroleum-based product. To combat this, some insulation installers, Ecotelligent included, have stopped using hydrofluorocarbons (HFC), a group of blowing agents, that release heat-trapping chemicals and harm the ozone. Those that choose to use HFCs will have a spray foam insulation with a higher Global Warming Potential (GWP) and be more harmful to the environment. At Ecotelligent Homes, our spray foam insulation has a GWP of 1, since we do not use HFCs.

Sheep’s Wool

Sheep have the ability to live in some of the coldest climates because of their wool. Due to this, scientists decided to use their wool to start insulating homes. Sheep’s wool has an R-value between R-3 and R-4 per inch making it comparable to or better than other forms of green insulation. It can be installed throughout your home in your walls, attics, ceilings and floors.

The outer layer of sheep’s wool is naturally water resistant and the inner layers have the ability to absorb approximately one-third of its weight in moisture without appearing damp. When sheep’s wool absorbs water, it generates heat and prevents condensation. These factors make it an excellent green insulation option.

Cellulose Insulation

Cellulose insulation is made out of recycled newspaper, making it an environmentally friendly type of insulation. Ecotelligent Homes uses shredded newspaper that has been treated with borax to make cellulose insulation that is fire-resistant and deters pests. The newspaper can also be treated with boric acid or ammonium sulfate, which can smell when it gets wet, to form fire-resistant cellulose insulation. The chemicals do take away some of its environmental friendliness, but overall, it is still a strong green insulation option due to its higher R-value. The R-value of cellulose insulation is between 3.2 and 3.8 per inch.      

Cellulose insulation can be blown into existing wall structures and attic spaces. It should not get wet because its heat-retaining properties will decline so it is best used where water will not be an issue. When cellulose insulation gets wet, it also loses its fire-retardant properties, which is a safety hazard.   


Denim or cotton has an R-value comparable to cellulose insulation at R-3.5 per inch. Demin insulation is made from recycled scraps of denim, often from old jeans or scraps from jeans being made. It can be purchased in batts so it is easy to install between wall studs and ceiling joints.

Denim insulation is treated with EPA-registered fungal inhibitors for protection against mold and mildew. It also helps to protect against pests. To be fire-resistant, denim insulation is treated with borate.

Fiberglass Insulation

Fiberglass insulation was once the top go-to for home insulation. The insulation is made up of tiny fibers of glass. The glass comes from sand, a natural and renewable resource, making fiberglass insulation a green insulation option. Not only does glass come from a natural resource, but the glass also used for fiberglass insulation is often glass bottles that are recycled and melted down. While it is using renewable and recyclable materials the process to make the glass and fiberglass is energy intensive and leaves more of a carbon footprint than other forms of insulation.

The R-value of fiberglass is R-3.14 per inch making it slightly less effective than other forms of green insulation. It’s most frequently seen in blanket form (batts) making it ideal for between studs, but it can also be purchased in pre-cut lengths and widths in a bag. It is very versatile and can be used throughout much of your home.   

Rigid Cork

Rigid cork insulation comes from the outer bark of oak trees. Harvesting this outer bark does not harm the trees, meaning it is a renewable material. It is formed by compressing cork granules into large blocks that are then cut into sheets to be used as insulation. The R-value of rigid cork insulation is between R-3.6 and R-4.2 per inch. Cork insulation is also resistant to moisture, mold and insects, making it a durable and long-lasting insulation material.

In addition to its high thermal barrier and eco-friendly properties, rigid cork insulation is said to have soundproofing benefits as well. It can be used virtually anywhere in your home that is exposed and can be used in walls if the studs are exposed during a remodel or before drywalling. 

Do you want to make your home greener?

Contact Ecotelligent Homes to help make your home more energy efficient. We can conduct an energy audit to discover areas of your home that could benefit from energy efficient upgrades such as new insulation.