Circle-top Window Energy Efficiency
October 11, 2010
Circle-top windows are a great way to add some pizazz to a room or the entire front of your home when you're replacing your windows, and they can be used over just about any style of window or door. While these windows can be an attractive addition to your home you don't want to sacrifice energy dollars to use them; you should expect your circle-top windows to be as energy efficient as any other replacement windows in your home.
Circle-top Windows Energy Efficiency Considerations
Circle-top windows don't open, which can eliminate many of the sources of air infiltration that other types of windows have, but there are still areas of the windows that can affect your home energy savings. Even though circle-top windows have a fixed sash, it is important that the sash fits into the frame securely and is sealed properly; you should not be able to move the sash in the frame.
Glass is an important factor with circle-top windows energy efficiency, and you should choose windows with double or triple panes whenever possible. Circle-top windows go through the same energy efficiency testing as most other windows, and two test result numbers you should pay attention to are:
- U-Factor. This test measures the airflow through a window over a period of time. Low U-Factor numbers usually mean the window is more energy efficient
- Solar Heat Gain Coefficient (SHGC)..This test measures the amount of radiant heat from the sun allowed through the window. Since most homeowners don't install window treatments over circle-top windows to block out the sun, this number can mean a lot for your long term energy savings. SHGC test results that are low are considered good
Circle-top windows have an irregular shape and can be difficult to install and seal properly so you may want to use a professional window contractor to make sure your replacement windows are installed correctly.