Casement Window

 

A casement is a window that is attached to its frame by one or more hinges at the side.[1][2] They are used singly or in pairs within a common frame, in which case they are hinged on the outside. Casement windows are often held open using a casement stay. Windows hinged at the top are referred to as awning windows, and ones hinged at the bottom are called hoppers.

Casement windows are labelled in one of two ways. FCL refers to a left-handed window, where the hinges are located on the left and the locking mechanism is on the right. FCR is a right-handed window with the hinges on the right and the locking mechanism on the left.[citation needed] Remember, these definitions apply to a window when looking at it from the exterior. Diagrams of casement windows show a dashed triangle with the hinged side identified by the point of the triangle. FCL windows feature a triangle pointing to the left; FCR windows have a triangle pointing to the right.