 |
...Continued - Page 4 of 4 (
1
2
3
4
)
Related Showrooms
• RadiantGUARD.com - Research & buy radiant barrier and save energy
• PexSupply.com - Your Online Source for PEX Plumbing & Radiant Heating Supplies
• White Lightning Caulk - Caulks and Sealants – Protect, Beautify and Save Energy
• Sears - Heating & Cooling Repair
Installation
Loose-fill insulations are typically installed with special equipment that blows the insulation through a hose and into the cavity. Although loose fills can be installed in both new and retrofit situations, they are especially popular for retrofit projects because they can be installed with minimal disturbances to existing finishes.
Installation often calls for the "two-hole method," which entails drilling two holes spaced vertically between the exterior walls' framing studs. The holes should be 2 inches (5 centimeters) in diameter. Working between each stud, drill one hole 16 inches (41 centimeters) from the top of the wall. Drill the other hole 24 inches (61 centimeters) from the bottom of the wall. The insulation is blown into the holes, then the installation holes are sealed. Installation is most commonly done by professionals who are experienced at operating the equipment to ensure proper density and complete coverage. In conventional and cathedral ceilings, insulation is easier to blow in if an access opening through the ceiling already exists. Otherwise, it may be necessary to drill holes in the ceiling or between the roof rafters.
Cost
At the time this publication was written, the average loose-fill insulation cost per R-value per square foot was about 0.8 cents for cellulose and rock wool and 1.1 cents for fiberglass. These prices were for materials only. The average installed price per R-value per square foot was about 1.2 cents for blown-in cellulose and rock wool and 1.3 cents for fiberglass. Because prices vary in different regions, obtain bids from several insulation contractors or suppliers to determine the specific cost in your area.
Installation Quality Control
Voids and Gaps - To ensure a quality installation, there are several things to watch out for when installing loose-fill insulation—whether you do the job yourself or hire a professional.
You may create undesirable voids or gaps if you install the insulation at too low a density or if you do not completely fill the cavity. Voids are most likely to occur at the top of wall cavities, above windows, around doorways, and in the corners of ceiling cavities. Voids also occur if the installation holes are improperly located between the vertical framing studs or if there are too few fill holes. Keep in mind, though, that installers' practices may vary regarding the number, location, and size of installation holes.
It may be difficult to achieve recommended R-values with loose-fill insulation in the eave area of the attic. There are insulation techniques that can be used to insulate this area adequately.
Fluffing - "Fluffing" occurs when insulation is installed to minimum thickness but not to minimum weight requirements. The result is a less dense application of insulation that requires fewer bags. When insulation is "fluffed," air passes more easily through it. This means increased heat loss. Additionally, the fluffed loose-fill insulation will eventually settle and result in a thinner layer with a lower overall R-value. Fiberglass is more "fluffable" than cellulose or rock wool.
Intentional fluffing by unscrupulous contractors has been a problem in some parts of the country. To avoid these problems, compare bids from several contractors to see how many bags they specify. Count the number of bags used during installation, either by you or a contractor, and compare it to the instructions on the bag. The manufacturer should specify the amount of insulation required to obtain a particular R-value per square foot (or square meter) of space.
Safety and Health Concerns
Safety Guidelines - Insulation blown into your ceiling cavities should cover the top plate of the wall, but be sure the eave vents are not covered. These vents provide necessary ventilation to your attic, and covering them could result in severe moisture problems.
Electrical devices and recessed lights (except "IC-rated" fixtures) require 3 inches (8 centimeters) of clearance from insulation.
Pipes for kitchen stoves, wood stoves, and furnaces should only be insulated with fiberglass or rock wool because cellulose may smolder if flue temperatures become hot enough.
Health Considerations - Some observers contend that fiberglass particles can cause cancer if inhaled, and others state that the fire retardants and insecticides added to cellulose may be harmful to breathe. While the debate continues as to the health effects of loose-fill insulations, it is important to protect yourself when installing any type of insulation. Wear a quality respirator, and wear protective eyewear and clothing such as goggles, gloves, long-sleeved shirts, and pants to minimize contact with the insulation.
Insulation fibers can also be drawn into air distribution systems if the ducts are not properly sealed, allowing the fibers to circulate within the living space. Be sure to seal all of your home's ductwork, as well as any other openings where insulation could leak out of the wall or ceiling cavities and into your living space.
Conclusion
Cellulose, fiberglass, and rock wool loose-fill insulations are good choices for many insulation projects. However, they are not suitable for all situations. Conduct careful research and consider factors such as your climate, building design, and budget when selecting the best insulation for your specific circumstances. If you control air leakage and ensure that the insulation you select is installed properly, you can reduce your energy bills and enjoy a more comfortable home.
|
© 2004 U.S. Department of Energy
...Continued - Page 4 of 4 (
1
2
3
4
)
< Previous Page
- Add To:
-
 Del.icio.us
-
 Digg
-
 Google
-
 Y! MyWeb
-
 Reddit
-
 Technorati
|
|
Related Articles
Related Tips
Related Videos
