The Federal Trade Commission warned 14 window manufacturers and one window glass manufacturer that they may be making unsupported energy savings claims for replacement windows. The warning letters are part of an FTC effort to ensure that environmental marketing is truthful and based on solid scientific evidence.

Each letter states that the FTC reviewed the company’s website and found claims similar to those challenged in administrative complaints the FTC filed earlier this year against five companies. Those companies agreed to orders barring them from making exaggerated and unsupported claims about their windows’ energy efficiency and how much money consumers could save on their energy or heating and cooling bills by having them installed.

The warning letters highlight claims that consumers will save more than 30 percent on their energy or heating and cooling bills by installing replacement windows. The letters state that the FTC has made no determination whether the companies are violating the law, but urge the recipients to review their marketing materials with the following in mind:

  • Energy-savings claims must be backed by scientific evidence.
  • Be specific about the type of savings consumers can expect.
  • Avoid deception when making “up-to” claims.
  • Avoid deception when selecting home characteristics for modeling.
  • Clearly and prominently disclose any assumptions.
  • Exercise care in using testimonials or “case studies.”
  • Manufacturers may be liable for misleading or unsubstantiated claims made to dealers or retailers, in addition to claims made directly to consumers.

The letters were sent to glassmaker Cardinal Glass Industries and window manufacturers Acadia Windows & Doors Inc., Nationwide Window & Siding Corp., Newpro, Pace Window & Door Corp., Pal Windows, Ringer Windows, Sierra Pacific Windows, SureGuard Windows, SwissShade & Security, Inc., Thompson Creek Window Company, Value Windows & Doors, Vytex Windows, Weather Shield (and its glassmaking component), and West Window Corp.
To learn about factors affecting the energy savings replacement windows are likely to provide, read Shopping for New Windows.

The Commission vote to publicly disclose the warning letters was 5-0. Copies of the letters can be found on the FTC’s Web site at