Eco-Friendly Insulation

Written by Morgan Kaenzig de Denus, AMAST Content

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High-quality insulation can reduce heating and cooling costs by 20% and reduce CO2 emissions by 780 million tons. Properly installed insulation can help prevent air from entering and leaving a building, which helps buildings stay cool in the summer and warm in the winter. A properly insulated building will save 600 times more energy than using compact fluorescent lights, Energy Star appliances, and Energy Star windows combined will save.

Today, fiberglass insulation is a popular choice. However, fiberglass insulation contains hazardous fibers and is not very eco-friendly. Many other insulation options are more eco-friendly than fiberglass insulation.

Wool Insulation

Wool is a sustainable and cheap form of insulation. It is a natural and renewable resource that is composed of several amino acid chains. These amino acid chains react with and neutralize harmful substances like sulfur dioxide, nitrogen dioxide, and formaldehyde through the process of chemisorption. When wool is compressed, air pockets will form. These pockets of air will help keep the building cool in the summer and warm in the winter.

As a loose fill insulation, wool can be installed by hand or with the use of a blower. Wool has an R-value of 4.3 per inch, but, since it is a form of loose fill insulation, there will not be an airtight seal, and its R-value may become compromised.

Cork Insulation

Cork insulation is another excellent choice. Cork has a honeycomb structure and consists of hollow polyhedral cells. Each cell has 14 cell walls that are airtight, waterproof, flexible, and strong, giving cork a low density and a reputation as an effective thermal and acoustic insulator.

Denim Insulation

Denim insulation has an R-value of 4 at 1 inch, making it an effective insulation choice. It is often made of recycled fiber textiles like old jeans, which diverts materials from the landfill. If denim is treated with boric acid, it can become more fire retardant and discourage the growth of molds and fungi.

Straw Bale Insulation

When stacked closely together and sealed with earthen plaster, straw bales are an excellent form of insulation. It is a cost effective and sustainable way of insulating a building, as straw is 100% biodegradable, non-toxic, and a natural byproduct of agricultural harvesting.

Despite its biodegradability, straw bale insulation can last for over a century. Straw bale construction has a degree of fire resistance because the bales are packed so densely that there is not enough oxygen to encourage flames to spread.

Straw has a relatively low R-value of 1.9 per inch. However, the standard two-string straw bale measures 18 inches wide, which can increase its effectiveness as an insulator. Unfortunately, using standard two-string straw bales also reduces the building’s usable square footage.

Loose Fill Cellulose Insulation

This type of insulation does not have any harmful chemicals, and it consists of recycled materials, making it environmentally friendly. Most cellulose insulations consist of recycled newspapers, wastepaper products, cardboard, or office paper.

Loose fill cellulose insulation is a cost-effective and environmentally friendly way of insulating a building. It also has an R-value of around 3.5 per inch of thickness.

Hemp Insulation is a plant-based form of insulation is naturally resistant to molds and pests. Hemp insulation consists of hemp fibers, which may be treated with a salt-based fire retardant. Hemp is a natural product, and it is 100% biodegradable. It also has an R-value of around 3.7 at 1 inch.

Mushroom Insulation

While mushroom insulation is not quite ready for production or use on a mass scale, it is likely to become a viable insulation material in the future. Researchers have been creating insulation from mycelium, which is the vegetative part of mushrooms. Mushrooms are allowed to feed on substrates to encourage mycelium growth. The fungus will then grow to fit the shape of the mold.

When the fungus has filled the mold, it can be dried, sanded, and painted. The resulting material is 100% biodegradable and natural. It is also self-extinguishing and can remove carbon from the air.


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