Attic Insulation Resources
By Owen Whetzel
Put simply: Adding or increasing the amount of attic insulation to your home, offers great potential for energy savings and increased comfort, and the pay-back on the cost of the insulation should be fast.
Look at R-value, when purchasing insulation. R-value measures the effectiveness of an insulation material. The "R" stands for "resistance," the ability of the material to resist the flow of heat. The higher the R-value, the more effective the insulation. However, a sloppy installation can decrease the effectiveness of the insulation, particularly compressing batts of insulation or leaving gaps (other than for attic ventilation or any heat producing device, such as lighting fixtures, furnace flue or vents, exhaust fans, etc.).
You will likely need a minimum total attic insulation of R-38 (you can exceed the minimum if you wish), but more may be needed, if you live in an area with freezing winter or hot summer temperatures. A good place to start gathering information is "Determining the R-Value You Need for an Existing House," prepared by the U.S. Department of Energy, Oak Ridge National Laboratory. This site will also allow you to calculate the amount of insulation needed for wood frame wall cavities, under-floor, basement wall interior, insulative sheathing on empty wall, and adding insulative sheathing to R-11 wall, based on your zip code.
If your attic has some insulation in place, measure the depth and take a small sample of the material to the Industrial department in an Orchard Supply Hardware store. You should be able to get specific recommendations on what you need to increase the total value to the needed depth or you can compute what you need yourself. For example, if you know that the attic currently has R-19 insulation and you need R-38, deduct 19 from 38. The difference tells you that you need to add insulation with an R-19 value. However, what you should purchase and how much depends upon a number of factors and the climate in which your house is located.
When adding insulating batts, remember to buy material without a foil or paper face (the moisture barrier), or you must make slices in the facing material, so that you don't trap moisture between the old and new insulation. Another option, preferred by some energy experts, is to install plastic encapsulated insulation as a second layer. Plastic encapsulation not only makes installation easier, but also reduces the negative effects of condensation on insulation. A second layer of insulation is usually laid perpendicular to the joists.
Be certain to follow all of the insulation manufacturer's instructions and warning carefully. Is placing insulation a good do-it-yourself project? Yes and you should be able to see the results of your efforts each time you receive a bill for the cost of heating or air conditioning.
Additional help: An article worth reading, although it is from September/October 1996, is "Home Energy's Consumer Guide to Insulation," which is on the Home Energy Magazine Online Web site. The publication of this article was made possible through funding from the U.S. Environmental Protection Agency and the U.S. Department of Energy's Office of Building Technologies.
Also read: "insulate" on the Web site of the California Energy Commission. For answers to specific home insulation questions, contact the California Energy Commission, 1516 Ninth St. Sacramento 95814. Phone: (916) 654-4287.
Links to insulating information:
-- "Insulating at a Glance" can be found on the Owens-Corning Fiberglas Technology, Inc. Web site. A printed version of the information on the Web site, "Homeowner's Insulation Guide" is available by phoning Owens Corning, (800) GET-PINK (438-7465) or may be requested through the Web site, http://www.owenscorning.com/around/literature.asp.
In addition:
-- "136 Best Ways to Save on Your Home Energy," by the editors of Sunset Books (Sunset Books).
-- "Quick Guide: Insulation and Ventilation," by the editors of Creative Homeowner (Creative Homeowner)
-- "Insulate and Weatherize: Expert Advice from Start to Finish," by Bruce Harley (The Taunton Press)
-- "Popular Mechanics Weatherproofing and Insulation," by Albert Jackson and David Day (Hearst Books)
-- Check with a library for books on insulation, as well as magazine articles. A periodical or Web search using the keywords "home insulation," "weatherization," "weatherstripping," and "home energy savings" may provide you with some of the latest information.