National Fenestration Rating Council
www.nfrc.org

Efficient Windows Collaborative
www.efficientwindows.org

U.S. Department of Energy
www.energy.gov

Energy Star
www.energystar.gov

Alliance to Save Energy
www.ase.org

Window and Door
Manufacturers Association
www.nwwda.org

National Sash & Door
Jobbers Association
www.nsdja.com

Center for Energy Efficiency
and Renewable Energy
Umass Fenestration Research Page

Lawrence Berkeley National Laboratory
www.windows.lbl.gov

Forest Products Society
www.forestprod.org

National Technical Information Service
www.ntis.gov/index.html
 

National Renewable Energy
Laboratory for Buildings 
and Thermal Energy Systems
www.nrel.gov

American Wood Fibers
www.awf.com

American Forest & Paper Association
www.afandpa.org

State Energy Codes
www.naseo.org

National Association 
of Home Builders
www.nahb.com

Western Wood 
Products Association
www.wwpa.org

Center for Sustainable
Building Research
www.csbr.umn.edu