Speaking of Windows

"Speaking of windows
Windows used to be little more than a hole in the wall keeping out weather elements. Today’s attitude is that windows are a wall you can see through while remaining comfortable. In the average home windows cover from 10 to 15 percent of the total wall area, yet they are responsible for 20 to 30 percent of the total home-energy loss.
Windows can be the cause of significant heat loss in winter and cooling loss in the summer. This loss is often around the window and not through the window itself. Proper caulking and spray foam insulation are key to minimize heat loss. The insulation value of glass is not very high and this is another large contributing factor to these losses. This is often combated with gas filled units and special coatings on the glass.
Good windows keep energy costs down. They reduce drafts, increase the home’s comfort level, block exterior noise, provide fade protection to carpeting and furnishings, and increase the value of the home.
Windows have three integral parts: glazing or glass, edge spacers and frame. Each contributes to, or detracts from, a home’s comfort level. Each conserves or wastes energy.
Single-paned windows offer little or no insulation. Two panes of glass are more energy efficient than one, and three panes are even better. For our climate zone ""3"" Pioneer Window recommends triple pane windows with Low E glazing and argon gas filled spaces.
Low-E glass uses a colorless, almost invisible coating that transmits high levels of light but reflects heat. Soft coat Low E, another energy-efficient glazing option, allows for cooler rooms in the summer by transmitting less heat into the room. Some windows have argon gas between the panes. Because this gas does not conduct heat as fast as air does, it can deliver efficiencies higher than any other type of window.
Edge spacers that hold the glazing layers apart used to be made of aluminum which conducts heat rapidly. Today they are made of materials such as structural foam that conduct heat more slowly. We recommend warm edge super spacer which we use in all of our windows.
Frames make up 10 to 30 percent of the total window area. The framing material used can make a difference in the efficiency of the window and, consequently, the energy cost to heat and or cool the home. Metal frames conduct heat faster that other window frames. Metal frames with a thermal break, a plastic insert that separates the inside metal framing from the outside, conserve energy. Wood frames conduct heat much more slowly than metal, but require more maintenance. Today some wood windows are available with metal cladding which can reduce the need to paint. Vinyl frames have an efficiency far greater to that of wood and they require less maintenance.
How do you know when you need new windows? A rule of thumb is, “if you feel air when sitting or standing next to the window, you know that moisture and air is coming through”.
Determining the best window to buy depends on a number of factors, including budget. Orientation of the window is another factor to be considered. Windows used to be rated with R-values, the measure of resistance to heat transfer at the center of the glass. The higher the R-value, the better the window’s insulation ability. A new system, the U-value, usually displayed on the window, measures the efficiency of the entire window unit. Typically, U-values range from 1.15 to 0.15. The lower the U-value the less heat transfer between the inside and outside air. Some numerical ratings to look for are Solar Heat Gain Co-Efficient (how the sun warms up the inside of your home) Air Infiltration (resistance to air movement from inside to outside) Design Pressure (how much pressure from window or pressure difference the window can withstand) Water Penetration (how much water the window can withstand) Forced Entry Resistance (how easy someone can break into the window)
No matter how energy-efficient a window is, proper installation is necessary to assure that the window performs to its potential. Windows need to be weatherized and insulated when installed. Qualified installers such as our own factory trained ones provide this service."