Do not ‘cram’ insulation
Q: I’m a do-it-yourselfer who built our family room last year. It was terribly cold in the room this winter and someone told me I might have ruined the insulation by cramming it tightly into the walls. Can this really cause a problem?
A: Yes it can. When you see the R-value (how well the material resists heat) of insulation on a package, that refers to the rating when the material is installed at its full thickness and is not compressed to fit spaces. If you’ve done much building, you know that sometimes you need to really squeeze insulation into walls so that you have room for pipes, wires or other building materials in the wall.
The problem is simply that compressing insulation dramatically cuts down on its effectiveness. If you have a fiberglass batt with an R-value of 11, for example, this means that it is rated at that number based on its full size. If your project forces you to squeeze the material down to only two inches thick to fit the space, you’ll cut the performance to around R-7.
This may be what caused your room to be so uncomfortable this winter. You basically don’t have anywhere near the insulation level you thought you did.
In future projects, take care to put wires in a notch at the bottom inside corner of the wall or at the center of the studs. Make sure that nails you drive intro the baseboard trip don’t pierce the insulation. When you put wires into the space, tear apart the insulation and put it in front of and behind the wiring or just put some insulation patches behind the wires.
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Q: We’re buying a new home soon and we like one that has a finished basement. Do you think we need a radon test done on it or is that not a problem anymore?
A: Regardless of where you’re located in the U.S., I recommend that you have your home tested for radon, especially if there are living areas below ground level.
This has become an energy issue because of the implications of reduced airflow in tightly constructed houses. While most researchers feel that cutting down on unwanted airflow in and out of a house doesn’t in itself cause indoor air problems, the reduced air infiltration may make problems like radon more serious.
Information from the U.S. Environmental Protection Agency indicates that about one of every 15 homes in the country has elevated radon levels, with some areas having more problems than others.
Radon is a radioactive gas that comes from the natural decay of uranium. It is found in nearly all soils. You can get more information on radon levels in your area by contacting your state’s Radon contact (visit www.epa.gov/iaq/whereyoulive.html for contact information dealing with radon and other indoor air quality problems).