ENERGY SAVINGS WHAT TO DO?
Look for the Energy StarŪ:
The Department of Energy (DOE) and the Environmental Protection Agency (EPA) have developed an ENERGY STAR (www.energystar.gov) designation for products meeting certain energy performance criteria. Since performance of windows and skylights vary by climate, product recommendations are given for the four ENERGY STAR climate zones.
Look for Efficient Window Properties on the NFRC Label
The National Fenestration Rating Council NFRC (www.nfrc.org) has developed a window rating system based on whole window product performance. The NFRC label provides the only reliable way to determine the energy efficient properties and to compare products. The NFRC label appears on all fenestration products which are part of the ENERGY STAR program.
Compare Annual Energy Costs for a Typical House
Computer simulations for a typical 2000 square-foot house are used to compare the annual energy performance of different window types.
Customize Energy Use Calculations for a Specific House
A computer simulation program, such as RESFEN (windows.lbl.gov/software/resfen), lets you compare window options by customizing calculations by adding heating and cooling costs for your climate, house design options, and utility rates.