Casement windows can be a single hung window like the above illustration or have multiple opening windows.
Casement Window Details:
Casement windows are side mounted on hinges, and swing open much like a door does. Their most unique feature is the crank mechanism used to open and close the window rather than the more traditional push or pull used on other window types. Casement windows most commonly swing outward, but can be purchased in an inward swinging style as well.
Fixed windows are the only style window to offer a tighter seal (and better draft resistance) than a casement window. Even thought they provide good draft resistance they still offer great ventilation when open. This is because the entire window can be opened rather than half like other windows. That larger opening also makes them an easier window to exit out of in case of emergency.
Casement windows are pretty low maintenance typically only requiring general cleaning and the hardware lubricated annually. you should be aware though that due to their design it may be harder to clean the outside of the glass particularly if the window is not on the ground level of the home.
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