Selecting Windows for Your Owner Builder Project
Double Pane Windows
Double pane windows are probably the most common available now. They offer a better insulated window than a single pane. However, the frame also impacts the passage of heat and cold and is probably an even more important factor since double pane glass is the rule rather than the exception.
Aluminum Window Frames
Aluminum window frames are the least expensive of the common frame types. They are sturdy and easy to install. However, metal is a strong conductor of heat and cold. This leads to a negative impact on your heating and cooling bills. They do sell Aluminum windows with double pane glass and low-E. This helps buy reducing the solar heat gain but you still have heat and cold transfer through the frame itself. You will have to weigh whether or not the savings up front from buying a less expensive frame exceeds the yearly costs in higher energy bills.
Vinyl Window Frames
Vinyl window frames have become very popular because they reduce the amount of heat and cold transfer. They are also less impacted by moisture. A vinyl window with Low-E ( low emmissivity) glass will reduce your energy bills over aluminum framed window with the same glass. The vinyl is more expensive than aluminum but has become more affordable as it becomes more common. It is a good idea to have your window provider bid both aluminum and vinyl and compare upfront costs vs. potential energy savings. Many renovation companies no longer carry aluminum or single pane windows because they are so inefficient.
Wood Clad Windows
Wood clad windows are generally the most expensive type of window. They can be very beautiful and are preferred in higher end homes. The wood can require additional care such as yearly paint or staining. Often there is a fiberglass core that makes them more energy efficient and less prone to twisting or warping. If your window budget is a bit higher and you are interested, have your supplier include a bid for wood clad windows.
If you are doing a window replacement or retrofit, wood clad windows can add considerable value to your home. They are especially popular in the Northwest and areas where there are historic homes in need of more efficient widows. Areas such as Portland have bustling historic districts where homes must be renovated under guidelines than may require wood clad retrofit windows.
Energy Efficient Windows
We have discussed the different frame types and how they impact energy efficiency. There are also specific features that a homeowner can request to increase the overall efficiency of their windows.
Low E Glass- Low E or emissivity coating is put on windows to deflect the suns rays and reduce solar heat gain in the summer time. Solar heat gain is when a window allows heat in but does not allow it to escape at the same rate, thus resulting in heat gain within the house.
Double Pane or Double Glazing- This is when two panes of glass with a gap of air or gas between are used in a window. The air acts as a thin wall of insulation.
Argon Gas- Argon has been used in double pane windows to fill the gap. This increases the insulation value of the window considerably and is an important component for windows installed in colder regions. It is also a more expensive option. Double check with your supplier if you live at a higher elevation. At certain very high elevations the argon has been know to shatter the windows as it expands.