Energy Savings: Proof is beautiful

"The best energy performance in window frames has been achieved using a fiberglass frame with foam insulation in the frame cavities."

-Consumer’s Guide, Natural Resources Canada


"Fiberglass has the highest "R" Value of all window frames."

-U.S. Department of Energy (DOE)

Most consumers agree that energy savings is the single most important environmental consideration when purchasing windows. Both Canadian and U.S. governmental agencies put fiberglass windows at the top of that list.

New Energy Rating (ER) numbers, developed by Natural Resource Canada and the window industry, show that fiberglass frames have the highest energy efficiency of any frame material – yes, performing better than PVC, aluminum and metal-clad wood frames. Similar evaluation by the U.S. Department of Energy concludes the same.

How is ER determined? The ER considers heat loss, resistance to air leakage losses and heat gain. Heat loss is a weighted average of all components: center of glass, edge of glass and frame. Heat gain is an average of the solar radiation for each direction (north, south, east and west). When combined with equally high-performance insulating glass, Accurate Dorwin windows receives one of the highest ratings of any product available.

Enjoy the confidence in knowing these facts speak for themselves. You are choosing the absolute best in energy savings for your home.