ENERGY EFFICIENCY
The Learning Center
Drafty windows and air infiltration could have several causes. Improper installation is often the culprit, but not always. If the windows were
improperly installed, the defects can normally be corrected without removing or replacing the window.
Proper caulking and flashing should prevent perimeter air leakage. However, if the installation bows, twists, or racks the window frame,
causing the sash weather strip not to be able to seal the sash to the frame, removal of the window to correct the problem may be
necessary. If the leak is between the frame and the sash and the window has been installed square, plumb, level, and is not bowed,
twisted, or racked, the problem may be construction of the window or window design.
If your windows are not efficient in your climate and if they do not have insulated glazing, the air may not be leakage, but simply cold room
air flowing down the surface of the window. As the window surface becomes colder, it cools the room air next to it. This cooled room air is
then heavier than the warmer room air farther into the room. Because the cooled room air is heavier, it sinks toward the floor and is
replaced by warmer room air, which is then cooled. This process can result in noticeable air flow, but it is not air leakage from the outside.
Replacement of the window by an energy efficient window is the solution here.
However, please keep in mind that no operable window can be made air-tight. If it were, it would not be able to be opened and closed.
Efficient window design, effective use of weather stripping, and proper installation should keep air infiltration to a minimum.
4. Why are my windows drafty and will new windows stop the draft?
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1-877-SWING CLEAN
info@energyswingwindows.com
3245 Miracle Drive
Murrysville, PA 15668
724-387-2991
PA Contractor ID
PA001856