Tips for Buying Windows
When you’ve decided it’s time to buy new windows, keep these considerations in mind to help you find the right windows for your home.
1. Replacement or New Construction Windows
New construction windows
New construction windows have a nail fin which is used to hold the window in your opening, just as if you were building a new home. Standard flashing procedures should be followed to insure the window does not leak the outside elements into your home.
Sometimes called retrofit windows, new construction windows are manufactured without a nail fin and have heavier frames than new construction windows. The window is installed with minimal or no disturbance to the outside area surrounding the existing window. A replacement window is installed in an opening by attaching through the head and jambs of the window.
2. Material Type
Aluminum windows are known for their impact resistance, which is desirable in Coastal areas with hurricanes and strong windows. However, they are susceptible to corrosion over time in humid environments and require a corrosion resistant protective paint. Aluminum windows aren’t as energy efficient as vinyl, as metal is a great conductor of heat, but they still have a number of energy efficient features and generally insulate better than older windows such as one-pane glass. They also cost about 20-30 percent less than vinyl impact-resistant windows.
Vinyl windows are an energy efficient, maintenance-free. Vinyl material insulates better than wood or metal, and doesn’t require upkeep like repainting. This is also a great choice if sustainability is important to you. In addition to energy savings, vinyl products are generally made from abundant natural resources and require less packaging.
Clad windows are made of wood and have either a vinyl or aluminum coating on the exterior which helps reinforce the wood and prevent against warping. These windows offer the insulating benefit of wood and the flexibility of color choice on the interior side without the maintenance cost. Aluminum clad windows can be painted in any color on the outside, however they are still susceptible to scratches & dents which can ruin color. Vinyl-clad windows are more durable but also more limited in options as they are manufactured in preset choice of colors.
3. Energy Efficiency Measurements
This nationally recognizing rating method by the National Fenestration Rating Council measures the rate of heat loss in a window. A low U-factor means the window is better able to resist heat flow and therefore more insulated. Low U-Factor is helpful during hot days when trying to keep the heat out, but isn’t quite as important as Solar Heat Gain in warm climates. For optimal energy conservation performance in Southern areas, the Energy Star® Associations recommends windows with a U-factor of 0.40 or less.
Resistance Value (R-Value) of a window refers to the resistance of heat conduction or the inverse of U-Factor. In other words – it’s another measure of heat flow. Unlike U-Factor however, an ideal window will have a high R-Value
Low Emissive or Low Emittance (Low-E) coatings on windows help control the loss and gain of heat and lowers the U-Factor of a window. This coating can add about 10-15% to your window cost but can reduce energy loss up to 30-50%.
Solar Heat Gain Coefficient
Solar Heat Gain Coefficient (SHGC) is the amount of solar radiation coming in through your window. While a high SHGC means you’ll get more warmth from the sun in the winter, a low SHGC is better in souther climates such as Houston, where you usually want to keep the heat out. The Energy Start® Associations recommends windows with an SHGC of 0.25 or less in Southern areas.
4. Special Area requirements
Near a Coast
When building or remodeling in a costal region, your local building code may require the use of an Impact Rated window. Impact windows have laminated glass and have been tested to stop flying debris from entering you home in the event of a hurricane. Most of these areas are classified as Seaward zones. A local building inspector can tell you if an impact rated window is required.
Near an Airport, busy highways or train tracks.
When building near airports some areas will require “Sound Reduction Windows” to be used. This is known as windows with an “STC Rating” or “Sound Transmission Control Rating”. Even if it is not required, these windows can make a difference in high activity areas. The window is designed to reduce the decibels of sound traveling through the unit. Typically, the STC rating will be between 35-40 with 40 being better. Standard windows carry an STC rating of between 27-30. A building inspector can tell you if you need this type of window.
5. Other Considerations
Safety Egress Codes
Egress windows offer an alternative exit in cases of emergency, such as a fire. These windows open directly onto a street, alley, yard or court with enough of an opening space for someone to fit through. Requirements will vary by county, so check with your local building inspector for details on size and location.
Be sure your install has made the precise measurements. This is especially important for replacement windows. Window openings need to be exactly square to order to fit and work properly. And imperfect fit with gaps will allow elements to seep in and damage your window as well as your energy efficiency.
As mentioned above, Vinyl materials are considered the most environmentally friendly. You can also check for the NAHB Research Center Green Approved mark, which signifies if the window is eligible toward a home’s National Green Building Certification.
The longer you’re planning to stay in your home, the more return you’ll get on improvements. Installing quality replacement windows will provide a higher payback in both energy bill and maintenance costs down the line.