People have been insulating their homes for hundreds, possibly thousands, of years. Ancient Egyptians and Vikings used mud to fill cracks for insulation, Europeans used straw and reed to build insulated thatched roofs, and Romans used cork to line the interior of their homes. In the late 1800s, straw bales were manufactured in the midwest and used to construct homes. Somewhere around the 1930s or 1940s fiberglass insulation was introduced when plastic was invented. There are now 100s of insulation options on the market.
To fully evaluate how “green” insulation is, it’s important to fully evaluate all angles of the product. Green building, as summarized by the U.S. Green Building Council, is the planning, design, construction, and operations that take energy use, water use, indoor environmental quality, material selection and the building’s impact on the surrounding environment and community into consideration. We can bucket these into four main categories: (1) Climate impacts, (2) Human health, (3) Material, and (4) Durability. Both material and durability also include the disposal and lifespan of a product.
For insulation, these categories can be explored to understand how green the product is. For climate impacts, the thermal resistance or the “R-value” is used to rate and compare a product. The amount of energy and water used to make the product also needs to be evaluated to fully understand climate impacts. For human health, off gassing or chemicals used in the product are evaluated. The material type and durability of insulation can be evaluated to understand how long the product will last (and still be efficient) and what happens to the insulation at the end of its life.
Environmental Working Group (EWG), a well respected organization that analyzes and identifies products that are healthy suggests that insulation should be Greenguard Certified or made of natural material, and flame retardants or formaldehyde should be avoided.
The insulation products listed in ecomedes (here) can be queried to determine insulation options based on the categories that owners and builders prioritize. The following list highlights five products that score higher on material type. These products are made mostly of renewable materials and are generally compostable in the natural environment.
1. Seaweed Insulation
Certifications: Cradle to Cradle Gold
Convert develops new materials from natural and mainly reused fibers ranging from recycled cotton and wool for furniture to seaweed for insulation. The Danish company has created insulation mats and roof ridges for thatched roofs out of seaweed, specifically eelgrass. This is a small company with few large scale projects. But with climate change and the plastic free trend growing, options like these will likely be used more and more often. Additionally, this company has used these fibers in molds to create chairs, offering an alternative to plastic. Covert’s parent company, Advance Nonwoven, also owns Naturecell, a South African start-up, that is launching bonded-cellulose fibre batt for thermal and acoustic insulation of buildings and HVAC systems made from recycled paper.
Check out Convert products on ecomedes - here
2. Wool Insulation
Company: Havelock Wool
Certifications: Health Product Declaration, Declare (International Living Future Institute), Red List Free
Havelock Wool is healthy high-performance insulation made from 100% sheep's wool. Wool is a fiber that has evolved over the past 10,000 years as the ideal insulator. Wool has a number of positive traits - wool filters harmful VOCs from your living space, actively manages moisture, and absorbs sound. The thermal conductivity of their wool batts are competitive with other insulation. Unlike most conventional insulation, Havelock Wool does not off-gas anything hazardous into the air nor does it emit harmful particulate. The installation process is simple and requires no special protective equipment (Havelock Wool’s website provides short videos describing installation process). As evidenced in their Environmental Product Declaration (EPD) and Life Cycle Assessment (LCA), wool has an extremely low carbon footprint and should therefore be considered when embodied carbon is a factor in building material decisions. Clearly there are many factors supporting that this is one of the greenest insulations out there.
Check out Havelock Wool on ecomedes - here
3. Wood Fiber Insulation
Certifications: Cradle to Cradle Bronze
Wood fiber insulation is loose-fill insulation material or fiberboards made from wood chips. Generally, wood fiber insulation is imported from Europe but there is a startup called GoLab that is planning to make wood fiber insulation products in Maine. For performance, the resistance is similar to cellulose and mineral wool, meaning it is similar to fiberglass, which tends to have the highest R-value.
KKS is a Danish company that has received a Cradle to Cradle Bronze certification for their Woodfiber Air insulation (loose-fill) product that allows a project to be eligible for a LEED Material Ingredient Disclosure Credit. This product is made of 95% wood fibers and is moisture-regulating. Like loose wool, wood fiber has lots of stagnant air in and around the wood fibers. This has a special heat-insulating but at the same time moisture-transporting effect, which ensures that no moisture damage occurs to the building.
Check out KKS wool fiber insulation on ecomedes - here
4. Cellulose Insulation
Company: Hamilton Manufacturing, Inc Thermolok™ Dustless Cellulose Insulation
Certifications: Biopreferred (100% Biobased Content)
Cellulose insulation is a fiber insulation material made from recycled paper and can contain up to 85% recycled newspaper (and cardboard and other papers) and come as loose-fill (often used in attics) or blow-in insulation (used in walls). Cellulose insulation is treated with ammonium sulfate, borax, or boric acid, making it fire resistant, though the idea of the product being made of newspaper is misleading.
Thermolok™ Dustless Cellulose Insulation is a blow-in insulation which creates a tight seal in walls and attics limiting air movement.
Check out Hamilton Manufacturing cellulose insulation on ecomedes - here
5. Recycled Denim Insulation
Company: Bonded Logic, Inc
Certifications: Recycled content 88%
Cotton, Inc.’s Blue Jean Go Green Program works with clothing companies (Madewell, Zappos, etc) to collect old denim, made of cotton fibers. The denim is recycled into UltraTouchTM Denim Insulation, and a portion is distributed each year to help with building efforts in communities around the country with partnering groups, mainly Habitat for Humanity.
UltraTouch Recycled Denim Insulation sets the standard for high performance insulating products that also focus on sustainability. Commonly referred to as the “blue jean insulation,” UltraTouch is made up of 88% post-consumer recycled content, mainly from old jeans. The thermal conductivity is higher than many other options. Plus, this insulation is reusing a product that would normally be heading to landfills that are quickly filling up around the world. This is another very green insulation option.
Check out Bonded Logic UltraTouch Recycled Denim insulation on ecomedes - here