Cellulose Insulation Problems

Typically, there are two types of insulation that are used in homes, cellulose and fiberglass. While fiberglass has become the prevalent material, many insulators still use cellulose. Insulation is generally blown in loose or installed in batts. Insulation should be present in attic spaces and walls to make a home energy efficient. Insulation serves to keep heat and cold air from escaping quickly to the outside. Insulating an attic space or ceiling properly is one of the single, biggest energy cost saving measures a homeowner can take.

Specifications

Cellulose is, essentially, recycled paper. The paper is treated with boric acid, sodium borate or ammonium sulfate in order to increase its flame retardation ability. Cellulose is an organic material.

Weight

Cellulose is about three time heavier than fiberglass. While cellulose has a slightly higher insulating factor (or R value) per inch, it also has a settling factor which fiberglass does not. This means it takes more cellulose to do the same job. This can be an issue, particularly in older homes, when the weight of the insulation exceeds that which the ceiling may be able to support. This will cause the drywall between the ceiling joists to bow.

Cleanliness

Cellulose, because of the material it is made of, tends to be very dusty. This is a factor when installing and can be a problem if the space is an area that may be used for storage or accessed regularly. When the cellulose is disturbed, it creates a significant amount of dust.

Durability

Cellulose is much more likely to retain water or remain damp if it gets wet. This can cause mold growth, especially due to its organic nature. Even if the cellulose dries fully, it is common for the insulation to develop a crusty surface from the process, which leads to an unwanted vapor barrier and additional moisture problems.

Safety

While cellulose insulation is treated for flame retardation, it is not fire resistant, or a Class A material. Cellulose can smolder if in contact with a heat source. This smoldering will travel through the cellulose insulation and can reach wood or other more flammable materials. There is also concern about the flame retardant chemicals not lasting on cellulose. The fact that the flame retardation is not inherent in the product, but an additional manufacturing step, leaves concerns about quality control possibilities.

Pests

Although this problem is less common, due to the addition of pesticides in cellulose, a concern is rodents and other pest nesting in the material. Again, cellulose is basically paper and it is appealing to many animals as nesting material.

Resources

• Insulation Issues to Beware of