Energy Efficiency

Replacing old windows with ENERGY STAR® qualified windows lowers household energy bills by 7-15 percent. Lower energy consumption also reduces greenhouse gas emissions from power plants and shrinks a house’s carbon footprint.

Energy-Efficient Windows – A Smart Investment

Replacing all of your home’s windows can be a big investment. The good news is, it’s an investment that can pay for itself in just a few years. Here’s how:

Sunny Window

  • 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
  • Increases your home’s security.

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.

What to Look For – Components of an Energy-Efficient Window

What’s an energy-efficient 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 window is a synergy of its components. At Milgard®, we call this the “three dimensions of energy efficient window design.” 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.

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Energy StarENERGY STAR® is a joint program of the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE). It’s mission is to help us all save money and protect the environment through energy-efficient products and practices. EPA and DOE set strict energy-efficiency guidelines for ENERGY STAR® qualified products. In 2007 alone, ENERGY STAR® helped Americans save more than $16 billion on their utility bills.

For more information on ENERGY STAR® qualified products, visit

To become ENERGY STAR® qualified, windows, doors and skylights must be independently tested and certified by the National Fenestration Rating Council and labeled according to ENERGY STAR® climate zones. Manufacturers like Milgard® (an ENERGY STAR® partner) tailor the components of their windows to work most efficiently where you live.

Energy Star Climate Zone-USA

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Increase Your Home’s Value

Home ValueWant to make a great remodeling investment in your home and feel good about it? Updating your windows could be the answer. Whether you select vinyl or wood windows to replace drafty old ones, you can recoup up to 69.1 percent of the project’s cost on your home’s resale value, according to Remodeling “Cost vs. Value Report.” New windows do so much for the look of a home inside and out and there are a lot of old windows out there that need some serious TLC.

Consider the following example. Someone is looking for a home to purchase and move into. They look at two houses exactly alike, everything is the same except one has brand new beautiful windows, and the other has old, dirty, drafty single pane windows. Which house do you think they are going to choose? How much is selling your home faster worth, when it comes time to do so? Special Offers and Rebates from ENERGY STAR Partners.

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Increase Your Home’s Security

Old windows and sliding glass doors are extremely unsafe! Most windows, even brand new windows put in new production homes can be easily broken into without even breaking the glass. Some old windows wear down with time, and many do not lock as well and add as much Window security as needed. Replacement casement style or double hung windows lock securely shut, making your house that much more secure and safe.

Home Security

If you’ve been thinking about replacing your old single-pane windows for more energy-efficient double-pane models, don’t put it off. Double-pane windows, especially if you opt for tempered or security glass, can be harder to break into than single pane. Plus, your new locks are likely to latch better than the worn-out hardware on your old windows.

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Or call us at 714-842-8850