Double-Hung Window Energy Efficiency
October 10, 2010
Double-hung windows can be a great choice as replacement windows for your home due to their timeless look and their ability to fit with just about any architectural style. Choosing attractive replacement windows can be an important consideration, but upgrading the energy efficiency of your home should also be a priority when replacing your windows and picking the right double-hung windows may provide you with energy savings for many years to come.
Double-Hung Windows Energy Efficiency: What to Look For
Shopping for double-hung replacement windows can be confusing as there are so many brands, styles, and options to choose from, and after awhile all the specifications seem to run together. Regardless of what brand or style you might be looking at there are three areas that can contribute to double-hung windows energy efficiency:
- Operation and sealing
- U-Factor
- Solar heat Gain Coefficient (SHGC)
Double-hung windows have two movable sashes. These sashes should feel tight in the frame, but not so tight that they are difficult to move. The top sash should fit evenly against the top of the frame and remain there without being held, and when you lock the sashes together there should be a feeling of snugness all around the window.
Double-Hung Glass Considerations
The largest part of a window is usually the glass, so it stands to reason that the glass in your double-hung windows needs to be energy efficient as well. Most windows go through testing procedures to determine their U-Factor and SHGC. The U-Factor is a measurement of the amount of airflow through the window over a period of time and the SHGC lets you know how much of the sun's radiant heat can get into your home. With both tests lower numbers are desirable and you can get even lower numbers with options such as Low-E glass and Argon gas between the panes.