Here’s Why Cellulose Insulation is Best for Your Attic
“R-value” (an expression of heat transfer resistance) is the standard for measuring insulation performance. At R 3.6 to 3.8 per inch, cellulose insulation is considerably better than most mineral fiber blowing wools. Some materials, such as foam plastics, may have higher R-per-inch ratings, but they are typically much more expensive.
Remember! Compare costs on the basis of the total R-value of the installation, not on the price of individual bags, boxes, or rolls. When you do, you’ll find that cellulose insulation gives you the most heat transfer resistance for the money.
In terms of national policy, the energy you save directly at home isn’t the only important consideration. Our country has emphasized energy conservation to reduce our dependence on foreign fuel sources and make America less vulnerable to international “energy blackmail.” If you are concerned about America’s energy independence, you need to understand “embodied energy.” Embodied energy is the energy consumed in producing products.
Mineral insulation comes from giant furnaces that gulp fossil fuel to melt sand, slag, or similar materials. Foam plastics are petrochemicals. They are literally made out of energy!
Cellulose insulation is made by processing recycled wood fibers through electrically driven mills that consume relatively little energy when they are operating, and which can be shut down completely with the flip of a switch at the end of the shift — or even for lunch and coffee breaks.
Fiber glass, rock wool, and plastic insulation have from 50 to over 200 times more embodied energy than cellulose insulation.
When you choose these products, you will certainly save on the amount of energy you consume at home, but you contribute to increased overall demand for oil and gas. And increased demand drives up prices!
All residential structures contain large amounts of wood. Cellulose insulation is the only wood-based construction material that is normally treated for fire retardant. This treatment makes cellulose insulation one of the safest materials used in home construction. The insulation is impregnated with borate. Our insulation is 100% borate and has the highest fire retardant properties.
If a fire occurs, the dense structure of cellulose insulation and its fire retardants slow its spread through the building by blocking flames and hot gases and restricting the availability of oxygen in insulated walls. Scientists at the National Research Council of Canada report that cellulose insulation “in the wall cavity provided an increase in the fire resistance performance of 22% to 55%.” Fire roars right through fiber glass. The NRCC study showed that “The fire resistance of an assembly with glass fiber insulation was slightly lower than that of a non-insulated assembly.”
Several fire demonstrations have been conducted in which cellulose insulated structures have remained virtually intact while uninsulated and mineral-fiber insulated structures were reduced to ashes.
Cellulose insulation is made from recycled wood fiber, primarily newspaper. One hundred pounds of cellulose insulation contains 80-85 pounds of recycled newsprint.
America’s cities are struggling with the challenge of solid waste disposal. Waste paper is a major part of the refuse stream. Today, more and more communities are addressing this problem through “curbside recycling” and similar conservation programs. These efforts work only if there is a demand for recycled products.
The federal government is attempting to create demand through such measures as the Environmental Protection Agency “Guideline for Procurement of Building Insulation Products Containing Recovered Materials” (40 CFR Part 248). Cellulose insulation unquestionably meets every provision of the guideline.
Paper that is not recycled ends up in landfills, where it may contribute to environmental pollution, or at incinerators, where energy is wasted reducing it to ashes, soot, and smoke.
When you choose cellulose insulation, you are making a positive contribution toward solving the solid waste disposal problem. That may help your community hold down taxes or refuse disposal charges. It certainly contributes to a cleaner environment.