Four Affordable Ways to Improve the Energy Efficiency of Old Windows:

There are many reasons to replace windows, but energy efficiency is not the best reason. Replacing the windows in an older house is one of the most expensive energy upgrades you can make. To improve performance of existing windows, consider storm windows, window films, and exterior roller shades before buying replacement windows.

But which option is the best bang for the buck?

BY PETER YOST

Read more: http://www.greenbuildingadvisor.com/blogs/dept/green-communities/four-affordable-ways-improve-energy-efficiency-old-windows#ixzz4XYy7AQE9 
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