ST. PAUL -- The Minnesota Department of Commerce issued a consumer alert Friday, encouraging Minnesota homeowners to think twice before installing radiant barriers in their attics.
The department says radiant barriers are not an effective means to reduce heating or cooling loads in Minnesota homes.
The Department's Division of Energy Resources has received reports of salespeople pitching radiant barrier products in fliers and at free dinners throughout Minnesota.
"Many Minnesota consumers have been duped into installing radiant barriers based on false promises of substantial energy savings," said Commerce Commissioner Mike Rothman in a news release. "We strongly urge all consumers to be cautious, ask questions, and explore other reputable means to make their homes and businesses more energy efficient."
Radiant barriers consist of a reflective film, usually aluminum, installed over the top of attic insulation in existing homes. They are sold as an energy-saving product, with claims of significant reductions in both heating and cooling costs. However, their potential benefit is primarily in reducing air-conditioning cooling loads in warm or hot climates -- particularly in southern states.
A report compiled by the Oak Ridge National Laboratory for the U.S. Department of Energy shows that the benefits of radiant barriers decrease significantly in northern climates. In southern cities like Miami, Florida or Austin, Texas, radiant barriers could reduce a household's utility bill by as much as $150 per year using average residential electricity prices. But in colder climate states such as Minnesota, where annual air-conditioning loads are considerably less, savings drop to only $10 to $40 a year.
"The price to install a radiant barrier can be as much as $2,000 or more," Commissioner Rothman said. "But if the average household saves only $20 per year, it would take 100 years to pay back your investment."
It's also important to note that radiant barrier products have negligible benefit in reducing heating costs. It is unlikely that most Minnesota consumers would realize any measurable energy savings from radiant barriers in attics.
The U.S. Department of Energy and the Minnesota Department of Commerce agree that, in Minnesota, implementing air sealing and adding conventional attic insulation is a cheaper and more effective means for saving energy than installing a radiant barrier. In fact, as attic insulation levels increase, the potential benefits from a radiant barrier decrease.
For more information on insulation and other energy-efficient measures to improve your home, contact the Minnesota Department of Commerce at 800-657-3710 or 651-296-5175 or visit www.energy.mn.gov. The website offers free downloadable home energy guides, including the "Home Envelope" guide that includes information on air sealing, insulation, and home energy audits.