Parts of a Window

Window Terminology: Understanding the Various Parts of a Window

If you’re thinking about replacing or upgrading the windows of your home or office, chances are the glass specialist or installer you hire might use some specialized terminology when discussing your window needs with you. There are more parts to a window than you might realize, and it helps to have a basic understanding of all the items a glass professional might refer to in the quotes they provide you.

Below is some window terminology to help you understand the parts that make up a window. After all, when you’re shopping for new windows, it’s better to have a clear picture.

Window Terminology

Window terminology can be divided into a few categories, such as the parts of the window frame, the glass itself, and the various safety and security features. Let’s start by taking a look at the parts of a window’s frame:

Window Frame Parts

• Window Frame – A window frame holds and supports the entire window within the wall. Made up of smaller parts like the sill, head, jamb, and apron. Usually made out of vinyl, wood, aluminum, or fiberglass. Window frames come in standard sizes or can be made custom.
• Sill – The lowest part of the window frame, the sill is sometimes called a ledge or a stool. It’s often wide enough to store items on if the wall and frame are deep enough and the sill is flat.
• Head – The highest or top horizontal part of a window frame.
• Jamb – Each vertical side of the window frame is called a jamb.
• Jambliner (or Jamb Liner) – A strip placed on the jambs to buffer the glass and the frame.
• Apron – An optional decorative trim installed beneath the windowsill that can aesthetically frame a window and add dimension.
• Casing – Another term for trim, casing refers to the decorative molding (framing) around a window that covers up and conceals the gap between the wall and the window frame.
• Panel – A broad term referring to a rectangular section of a surface, for instance, of a wall. A window panel can be made of several panes.
• Fixed Panel – The panel of a window that is non-operational, such as on a single-hung window, a piece of decorative stained glass, or a sidelight. An entire window can be a fixed panel window, i.e. a window that doesn’t open. A term often used to describe shower doors.
• Hinged Glass Panel – In a window with blinds that snap in between two panels of glass, the hinged glass panel is the panel that opens inward to allow for cleaning. In a shower glass door, the hinged glass panel is the part that swings or slides open.

Window Glass Parts

There are a variety of components that work together to hold window glass in place.

• Pane – An individual sheet of glass in a window.
• Sash – The moveable parts of the window that contain the glass. Sashes can be vertical or horizontal.
• Mullion – A structural element that combines two or more windows together.
• Muntins – Strips of material used to create the visual effect of multiple panes of glass.

Single-hung or Double-hung?

• Single-Hung Window – A type of window that opens via a single sash at the bottom of the window. When opened, single-hung windows are flush with the wall.
• Double-Hung Window – A type of window that opens from either the top, bottom, or both via two operating sashes. When opened, double-hung windows are flush with the wall.
• Check Rail: On a double-hung window, the check rail is the part where the bottom part of the upper sash and the upper part of the lower sash come in contact (the middle of the window).

Additional Parts of a Window

There are several important parts added to most professionally installed windows that improve their performance, safety, and security.

• Lock Handle– The lock located on the jamb to allow the window to be locked.
• Operator– A crank handle for opening and closing the window.
• Sash Lock – A locking mechanism that engages with the sash lock strike to reduce rattling.
• Weep Hole– A place where water and condensation can escape.
• Weather Stripping– Used on some style of windows to create a weathertight seal, usually made of a combination of rubber, vinyl, felt and metal materials.
• Balance – A counterbalance weight to keep some single-hung and double-hung windows open.
• Screen– A fine mesh made from fiberglass or aluminum that covers a window to keep out insects.
• Shades, Curtains and Blinds – Various types of window coverings that create privacy and protection from the sun.
• Hinges – Metal parts that allow the window to open and close by pushing and pulling rather than sliding. The location of the hinges varies based on the type of window.
• Window Film – A thin material that can be applied to window glass designed to protect inhabitants from UV rays and help regulate interior temperatures.
• Exterior Aluminum Cladding – A factory-applied finish on exterior windows that help protect wooden windows from the elements. This is not required of vinyl windows.

Types of Window Glass

You might come across the following terms used to describe types of glass or special styles of windows:

• Insulated Glass Windows – Windows that have special components like argon (a type of gas) to help make them more energy efficient. Also commonly referred to as double-pane windows.
• Vinyl Windows – Windows with frames made of vinyl instead of wood, aluminum, or fiberglass. Vinyl windows are easy to maintain, don’t require painting, and last a long time.
• Laminated Glass– A super strong type of glass that resists breaking. If a laminated glass window were to break, the laminate prevents the window from shattering into shards.
• Tempered Glass– A type of safety glass that has the same features as laminated glass but is heat strengthened and significantly stronger.
• Low-E Glass– Low-emissivity glass that is coated to reflect thermal radiation. This type of treated glass bypasses the need for adding window film to regular windows.

Consult the Window Experts

For all your glass and window needs in Nanaimo and surrounding areas, the team of glass specialists here at Budget Glass Nanaimo are here to help! We are happy to answer any questions you have about choosing the best type of windows for your home or office. Call us at (250) 758-3374 or schedule an appointment online.