Which Insulation Is Most Effective: Cellulose Or Fiberglass?
The foundation of your home’s energy-efficiency shell rests in the attic, most commonly as loose-fill cellulose or fiberglass insulation. Learn the primary strengths and weaknesses of both types of insulators to help you make the best decision for your home-efficiency upgrade or new installation.
Loose-fill cellulose insulation contains about 80 percent pulverized newspapers and other recycled paper materials, and 20 percent chemical treatments. It is installed using a pneumatic blowing machine, and conforms nicely to irregular structure shapes.
- Strengths: Since loose-fill cellulose is made from combustible newsprint, it is heavily treated with a fire-retardant chemical. This treatment also makes it resistant to insects, such as termites and cockroaches. Cellulose does not contain asbestos or formaldehyde, which other types of insulation may contain.
- Weaknesses: Studies have indicated that the fire-retardant chemical can leach out in as little as six months under certain circumstances, which creates a fire hazard. While cellulose has a higher R-value per volume than fiberglass, it is much heavier than fiberglass, and may not be suitable for many drywall ceilings in excess of R-19, as recommended for greater Pasadena-area homes.
Loose-fill fiberglass insulation, like cellulose, is sprayed into the attic and wall cavities using an automatic blowing machine.
- Strengths: Loose-fill fiberglass is an inorganic material (blown glass), which is naturally immune to insects, fire and mold growth. Loose-fill fiberglass does not settle over time to the extent of cellulose (fiberglass 2-percent settling vs. cellulose 20-percent settling), which means fiberglass retains nearly 100 percent R-value from the time of installation through the life of the building. Loose-fill fiberglass is about three times lighter than cellulose, and greater Pasadena-area homeowners may install the full R-38 recommended amount of insulation without threat of damage to the ceiling. Unlike cellulose, loose-fill fiberglass does not absorb moisture from the air, which means the R-value is not compromised.
- Weaknesses: Loose-fill fiberglass is a respiratory irritant. Proper protective gear must be worn during installation, and perhaps when going up into the attic afterwards.
For more information about insulation for your home, contact us at Air-Tro, Inc., and we’ll be happy to assist you.
Our goal is to help educate our customers in the Pasadena, California area about energy and home comfort issues (specific to HVAC systems). For more information, visit our website.
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