The Green Thumb
Not exactly high fashionMade from post-industrial waste or "mill waste," rather than post-consumer waste, cotton insulation appears to have many benefits such as no need for use of a binder such as formaldehyde, which is common in fiberglass. Also, cotton insulation has a low embodied energy to produce; fiberglass has a relatively high EE to produce (EE is the measure of the energy required to produce a finished product).
Seeing the possibilities for vertical integration, Greenwood Mills, of Greenwood, S.C., a large textile manufacturing company with an abundance of in-house mill waste fabric at hand, licensed the patent from Cotton Unlimited for Insulcot. A whole new subsidiary, Greenwood Cotton Insulation Products, was created by Greenwood Mills for the sole purpose of manufacturing and marketing cotton insulation. The company offered a line of insulation priced to compete directly with fiberglass and included: kraft-faced, foil-faced, unfaced and loose-fill attic insulation. Based in Roswell, Ga., the initial regional distribution targeted the southeast United States.
Insulcot utilized 95 percent post-industrial fibers, 25 percent of which was polyester fiber for improved recoil and tear strength. The main concern expressed over the use of cotton insulation is its flammability. Like cellulose insulation, which is essentially made from waste newspapers, cotton too is a combustible material. Similar fire-retarding additives used for cellulose insulation were used for Insulcot.
Heightening this concern, a plumber's torch ignited some exposed cotton insulation in a Habitat for Humanity home in Austin in March 1994. Installers of Greenwood Cotton batts found tearing by hand or use of a small circular saw worked best for cutting the materials. Scissors and/or a utility knife proved awkward. "Loft rebound," the ability of the insulation to recoil to its full thickness, was a concern.
When removed from the plastic packaging where it was tightly packed, the batts hardly expanded, unlike fiberglass, which readily expands. Greenwood recommended shaking the batts like one would a blanket but still, the loft rebound was poor.
On the bright side, there was unanimous agreement on the comfort level of installing the cotton insulation. No safety/protective equipment/clothing was required as is required for installing fiberglass and/or mineral wool. No watery eyes, skin irritations or full-body showers were required after installation.
In August 1998, Greenwood Cotton was purchased by Inno-Therm (www.inno-therm.com). Inno-Therm manufactures and markets cotton insulation under the name "Inno-Therm" using the technology and equipment that came with the Greenwood buy-out. Another manufacturer of cotton insulation is Bonded Logic Inc. (www.bondedlogic.com), manufacturer of UltraTouch cotton insulation.
In February 2000, from its manufacturing plant in Chandler, Ariz., (much mill-waste fabric is imported from nearby Mexico), Bonded Logic started to distribute UltraTouch. To increase fire resistance that would meet/exceed American Society of Testing Materials requirements for a Class-A building material rating (for wall and ceiling applications), Bonded Logic patented a proprietary process which "flash-washes" each fiber with a low-toxicity boron-based flame retardant to achieve a Class-1 fire rating for both residential and commercial applications. This treatment also serves to impede fungus/mold/mildew growth and resistance to pests. Proprietary microscopic olefin fibers are added to the cotton/fiber matrix, improving loft rebound after compression. By weight, the plastic olefin fibers and borate treatments constitute 15 percent of the insulation. The cleaned, cut and refiberized post-industrial cotton fibers are the balance (85 percent). Ultratouch achieves 3.4 R per inch and has a density of 1.2 pounds per CF.
Bonded Logic like to highlight the trio of benefits of cotton insulation:
For the latter, soundproofing, UltraTouch has excellent airborne noise (TV, radio, conversation, etc.) attenuation characteristics and achieves a noise reduction coefficient of 1.15 for a 51/2-inch batt. The 3-D structure of cotton fiber effectively traps, isolates and controls sound, which is in reality, wave energy. UltraTouch transmits 10 percent less airborne sound than comparable fiberglass batts.
Less is moreInstallation of UltraTouch requires no skin/eye protection or respirators. Since it contains no formaldehyde and/or chemical irritants, no potentially carcinogenic respiratory irritants, airborne particulates, volatile organic compounds and/or chemical offgassing result from the installation process.
In fact, the material packaging does not require any warning labels since it is inert. It is easy to handle and cut, and has the feel of a comfortable blanket. Thermal performance is also good-particularly in cold and windy regions. R-13 for 2-inch-by-4-inch framing and R-19 for 2 inch by 6 inch is achieved using UltraTouch.
Available unfaced only, the batts are blue in color and come in 8-foot lengths for 16 and 24 inches on center framing applications. The batts are oversized (width-wise) to allow for a tight friction-fit and full cavity fill. This significantly reduces the opportunity for air-convection and infiltration. The micro-fibers minimize "settling" of the insulation and microscopic air pockets maintain the thermal consistency of the building envelope, even in extreme temperature ranges. UltraTouch cotton insulation is permeable thus it "breathes" and will allow for "vapor-diffusion" and "dryout" if water/moisture saturation occurs.
The blue jean manufacturing process produces between 6 to 8 percent material waste. Formerly destined for landfills, where it decomposes, this mill waste material is now put to good use in the cotton insulation manufacturing process and is 100 percent recyclable itself-a double benefit which makes it an environmentally friendly "green" building product. As mentioned earlier, fiberglass requires significant energy resources to produce whereas cotton insulation does not. Cotton insulation is suitable for use with a vapor barrier, as well.
With significant improvements in fire-resistance and rebound, cotton insulation is making a comeback. Manufacturers such as Bonded Logic are intent on competing directly with fiberglass and mineral wool for market share. For its environmental benefits, cotton insulation can be considered a "sustainable" building product. Perhaps cotton insulation will make cotton "king" once more.