We spoke with three highly rated companies to find out why homeowners should make their windows more energy efficient and how they can do it.
Allan Ross: It's very difficult to make old windows more efficient. In order for windows to meet today's energy efficiency standards, it requires insulated glass packages with coatings that can only be provided with new windows. We offer a full line of windows that incorporate different levels of energy efficiencies as well as aesthetics.
Rhonda Steffes: A lot of times, we see people put plastic over their windows. It's a temporary fix. You could try caulking your windows if you see cracks in them. It won't do a whole lot for you, but it's something you could try temporarily. In the last 15 years, there have been a lot of advancements in energy-efficient windows. Low-E coatings have really helped. Low-E stands for low emissivity, which means lowering the heat flow through the window.
Michael Cavanna: Beauty, comfort, functionality and energy savings are just some of the advantages for replacing your old windows. Single-paned or older double-paned windows don't provide the energy-efficient benefits [that newer windows do]. We manufacture double-paned windows that use Low-E 366 glass, which includes three layers of silver and is specially formulated to provide more protection against the sun's heat.
What makes windows efficient?
Ross: There are four factors - the glass, the [Low-E] coatings on the glass, the dead air space, and the gas used [to fill that space]. Argon or krypton gases are both efficient.
Steffes: On our windows, we have 11 layers of coatings on the glass. Some windows use less than that, so their windows are not as energy efficient. In northern climates like ours, you want to look for windows with a low U-factor, which measures the heat escaping through the window. A U-factor value of 0.30 or lower is good. They also measure the solar heat gain coefficient, which is the amount of solar heat admitted through the window. Typically, a number below 0.30 is good.
Cavanna: Our glass also has a dual seal with an all-foam spacer [which keep the panes the correct distance apart]. It compensates for natural expansion and contraction but will always return to its original shape. That's something metal and plastic spacers can't do.
Steffes: The argon or krypton gas is odorless and nontoxic, and heavier and denser than room air, so the insulated windows don't allow the heat and cold molecules to transfer back and forth through the window. It's like invisible insulation.
Cavanna: We use vinyl window frames, which can be welded at the corners rather than being mechanically fastened or glued - which could mean potential corner separation when the house is settling or if there's an earthquake. They also have a low profile to maximize aesthetic appeal.
What's the cost?
Steffes: Our average job runs about $6,800. Of course, some people do two windows and some do 20. Purchasing and installing energy-efficient windows can cost between $400 and $800 per window.
Ross: There are obviously a lot of factors and features that can affect pricing, but you're looking at $500 to $1,500 per window for ones that meet the government's standards for the federal energy tax credit.
What certifications do your products have?
Ross: All of our windows are Energy Star rated, and they all meet or exceed the Energy Star requirements. Windows that meet the more stringent Federal Energy Tax Credit will allow a tax credit as well as provide energy savings that, over a period of time, will completely pay for the windows. Also, your home will get an updated look that gives you great curb appeal and increases your home's value.
Steffes: Our windows are certified by Energy Star and the American Architectural Manufacturers Association.
Cavanna: Our windows are Energy Star and American Architectural Manufacturers Association rated, and the energy they save certainly helps maximize a green-friendly environment.