What Should I Do About My Windows?

Should I get new windows, repair my existing ones, or buy retrofit products? Which strategy will save me more money on my monthly utility bills and make my house more comfortable? What is the best solution for my house and my budget?

As a building professional, you're asked these questions by friends, family members, and prospective clients. They may have turned to you because the only other source of window advice for most homeowners is a sales representative with just one solution: the product he or she is trying to sell. Whether it's storm windows or insulating blinds, replacement sashes or new windows, rarely does a salesperson offer alternatives. And the projected energy savings are all too often conjured from guesses and expectations, rather than from real data or calculations.

What makes valid energy savings projections particularly complicated is the lack of energy information for existing products. Although purchasers of new windows can find National Fenestration Rating Council (NFRC) ratings for U-factor and solar heat gain coefficient (SHGC) and Energy Star labels, these testing procedures haven't been applied to old windows or to many retrofit products, so consumers have few data to help make retrofit comparisons (see "A Window Glossary").