Energy efficient windows are one of best home improvement projects. Experts estimate that home owners recoup approximately 80% of the cost replacement windows when they sell their home. Between the cost savings from reduced utilities bills and the increase in home value, energy efficient windows can pay for themselves pretty quickly.
Even though windows make up roughly 10% of the surface area of your home they can be responsible for up to one-third of the energy lost so replacing your windows with energy efficient windows can have a significant impact on your utility bills in both the summer and winter.
Energy efficient windows also save you money because you may be able to purchase a smaller, less expensive air conditioner and heater which are also operate more efficiently. Your air conditioner and heater will also run less so they will get less wear and tear and last longer so you can avoid having to replace them.
Expected Energy Savings
The energy & cost savings you will achieve by installing energy efficient windows depends on several factors including the type of windows you currently have, the condition of your old windows, the orientation of your windows to the sun, any shade your windows have and how well your current and new windows are installed.
For more information on the expected energy savings from replacing the windows in your home with energy efficient replacement windows you can down download an Arizona Fact Sheet from www.efficientwindows.org.
The graph below depicts the estimated annual cooling costs of an average home in Phoenix, Arizona with various types of windows.
source: http://www.efficientwindows.org
Benefits of Energy Efficient Windows
Energy efficient windows have more benefits than just energy and cost saving. The benefits of adding energy efficient windows include:
- Save energy
- Save money
- Protect the inside of your house from ultraviolet rays (less fading of carpets, drapes & furniture)
- Your home will be cooler in the summer and warmer in the winter with less drafts
- Less dust in your house
- You can use a smaller, more efficient air conditioner (cheaper to buy and to operate)
- Your air conditioner will run less, reducing wear and tear, and last longer
How Energy Efficient Windows Work
The energy efficiency of a window is measured by its ability to restrict the transfer of hot and cold air in and out of your home. The three things that affect how well a window restricts the transfer of hot and cold are the glass, the sash and frame/seals. Heat is transferred directly through a window and by the sun rays and by air leakage around the seals. Cold is transferred directly through a window and by air leakage around seals.
Window manufacturers have come up with various ways to improve the energy efficiency of windows including insulating the sash, adding additional panes of glass, adding non-toxic gases between the panes, adding transparent films to the glass and improving seals. The most popular energy efficient windows are double pane windows. Glass transmits heat and cold very well but adding an extra pane of glass with a space between the two reduces the amount of heat and cold that are transmitted tremendously. The energy efficiency of double pane glass if further enhanced by adding Krypton or Argon gas between the panes and Low-E coatings to the glass.
The Most Energy Efficient Windows
It is not really possible to say that one particular window is the best energy efficient window or the most energy efficient. Different types and brands of windows excel in different situations. Some are better in direct, intense sunlight, others are better cold windy locations and others are better in wet, damp locations. One thing is certain, getting a more energy efficient window doesn’t always mean you will save more money. For instance, getting a double or triple pane window with low-E coating and Argon gas for a location that receives no direct sunlight will not save you any more money than a window costing half as much. To ensure you get
Cost of Energy Efficient Windows
Energy efficient replacement windows are one of the best improvements you can make to your home. They retain an estimated 80% of their cost when you sell your home and they are a great selling feature. Many things affect the cost of windows including: frame material, number of panes, size, style, coatings, gas fillings and manufacturer. You generally get what you pay for, meaning if two windows are the same size, style and have the same features, the more expensive one will generally be more energy efficient and will last longer. Home Depot has a great selection of energy efficient windows and is a great place to get an idea of how much it will cost to replace your windows.
Energy Star Program
“ENERGY STAR” is a government backed program that helps people save money and protect our environment through the use of energy efficient products and practices. Whether you are looking to replace old appliances, remodel your home, or buy a new house, ENERGY STAR can help. More than 60 types of products, including appliances, televisions, computers, heating and cooling equipment, and even new homes can earn the government’s ENERGY STAR label. ENERGY STAR also offers best practice solutions to make your home more comfortable and reduce your energy costs. Learn more at www.energystar.gov.
You may qualify for a Federal IRS energy tax credit, tax deduction or tax rebate if you replace your windows with Energy Star Windows. Check with your tax preparer to determine if you qualify.
Energy Saving Windows
Energy Star Qualified windows and doors are based on the climate zone the windows or doors will be used in. This helps consumers choose the right window for where they live. Further consideration should be given to a windows orientation to the sun when choosing windows.
All Energy Star Windows have been independently tested and certified according to test procedures established by the National Fenestration Rating Council (NFRC). NFRC does not distinguish between good and bad windows but using Energy Star ratings and guidelines you can identify replacement windows with superior energy savings.
Energy Star Windows
All Energy Star rated windows have an NFRC label with performance ratings in five categories. The five replacement window ratings assigned by the NFRC are:
- U Factor
- Solar Heat Gain Coefficient (SHGC)
- Visible Transmittance
- Air Leakage
- Condensation Resistance
Energy Star Qualified Windows are evaluated based on their U-Factor and their Solar Heat Gain Coefficient ratings only. Below is an example of an NFRC label.
Top Energy Efficient Window Manufacturers
- Anderson
- Pella
- Marvin
- Milgaard
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