Anatomy of a Window

Most people probably don’t really think much about their windows and what goes into them. They look pretty simple, but if you are in the process of buying new or replacement windows you are probably starting to realize that they are more complicated than you imagined. Depending on the type of window and the functions they perform, windows may actually be quite complex. Windows may provide ventilation, keep out the weather, provide security and need to open and close smoothly.  Purchasing a window will be easier if you understand a little about the anatomy of window.

Window Frame
The frame of a window is the fixed part of the unit which holds the sash and glass.

Window Sash
The sash is the interior framed part of the window. This part may be operable and holds the glass panes, spacer system and hardware.

Window Sill
The horizontal section of a window which forms the bottom of the window frame.

Head Jamb
The horizontal frame section at the top of the window.

Side Jamb
The vertical frame sections on the sides of the window.

Insulating Glass
Two or more panes of glass which are sealed with air between them. This is also called double or triple glazing depending on how many panes of glass are used.

Glazing
The glass portion of a window which is mounted in the frame.

Weather Stripping
Material which is used to fill the tiny gap between the operating sash and the frame. Weather Stripping helps to reduce the amount of air which escapes or enters windows and prevents moisture from getting into the home.

Grille 
The grille is the portion of the window which divides the glass in the frame and is used for decorative purposes only.

Casing
A decorative molding that covers the edges of jambs and openings between the window unit and the wall.