According to the U.S. Department of Energy, leaky and inefficient windows, skylights and doors account for up to 25 percent of the average household’s energy bills. Some sources estimate as high as 40 percent. A lot depends on where you live:
- Cold climates lose energy in the form of heat
- Hot climates lose energy in the form of cooling
The colder or hotter the climate, the greater your heating or cooling costs and the greater potential you have to save money on energy costs. Nearly everyone can benefit by replacing leaky, inefficient windows with modern energy-efficient windows. Depending on your location, you can cut energy costs by as much as 15 percent.
Replacing all of a home’s windows in Arizona can be a big investment. The good news is, it’s an investment that can pay for itself in just a few years.
- Improves curb appeal and increases resale value. According to the 2008/09 Cost vs. Value Report (a combined effort by Remodeling magazine and REALTOR® magazine), homeowners can expect to recoup about 93% percent for vinyl or wood window replacement.
- Reduces heating and/or cooling costs, which saves you money every year.
- Increases the comfort of your home.
- Can qualify you for rebates and tax incentives, like the Federal Energy Tax Credit, which provides up to $1,500 for any efficiency improvements made to your home in 2009 and 2010. (Save your sales order or NFRC label from the window and check for rebates and tax incentives in your area.)
To find out more about the many benefits of energy-efficient windows, visit the Efficient Windows Collaborative. The window selection tool on this site helps determine an approximate change in annual energy use given your home type, window type and geographic region.
What’s an energy-efficient replacement window? Most will have at a minimum:
- Double-pane insulated glass
- Heat-resistant (Low-E) glass coating
- Airtight frames
- ENERGY STAR® rating
Three Dimensions of Energy Efficient Window Design – An energy-efficient replacement window is a synergy of its components. Here’s what you should look for in each of the three dimensions: glass, spacer and frame.
Frame – One of the important considerations you need to make is frame material. Two of the more energy efficient frame materials are vinyl and fiberglass. They do a particularly good job of reducing heat transfer and contributing to insulation value. Your ultimate decision on which of these to use may be based on aesthetics and cost. In making your selection, be sure to look for vinyl or fiberglass frames that have been specifically engineered for performance. For instance, both can be designed with chambers within the frame that enhance strength, noise reduction and insulation value.
Glass – Dual-pane designs use an air- or gas-filled space between two panes of
glass. This insulates much better than a single pane. Special Low-E coating on the glass blocks infrared light to keep heat inside in the winter and outside in the summer. It also filters damaging ultraviolet light (UV) to help protect interior furnishings from fading.
Spacer – A spacer keeps a window’s dual glass panes the correct distance apart for optimal airflow between panes. Too much or too little airflow can affect the insulating glass efficiency. The design and material of the spacer also can
make a big difference in the ability to handle expansion and contraction and thus reducing condensation.