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Replacement Windows

What Are The Different Parts of a Window?

4 min read

Before you start shopping for replacement windows, or get your windows serviced, brushing up on window part names and window anatomy can help avoid confusion and make you more knowledgeable on what to look for in a replacement window.

At Window World of Long Island, our mission is to make purchasing replacement windows easier than ever. From energy efficiency to privacy and protection, check out our guide on the parts of a window. Each piece of a window serves a specific purpose and contributes to the overall efficiency of the window.

Anatomy of a Window Frame

The window frame surrounds and supports the window pane and can be made of aluminum, fiberglass, wood, or vinyl. Each part of the frame is a distinct component of a window:

parts of a window frame

1. Head

The horizontal piece at the top of the window frame is called the head.

2. Sill

The window sill is the horizontal bottom piece of the window frame. It is sometimes called a window stool.

3. Jamb

The jambs are the vertical sides of the window frame.

4. Apron

The apron is a decorative piece that is installed below the sill or stool of the window.

5. Weep Holes

Weep holes are openings built into the bottom of metal and vinyl window frames. They allow precipitation that collects in the window tracks to drain off.

Parts of a Window Sash

Your window sash is the moveable part of the window that houses the pane of glass. But it’s much more than just the part that holds the glass. Here are the components of a window sash:

parts of a window sash

1. Pane

The window pane is the piece, or pieces, of glass in your window.

2. Window Rail

The top and the bottom parts of sashes are called the window rails. Double-hung windows have four rails: two on the top sash and two on the bottom sash.

3. Spacers

Spacers are placed between the panes of glass double and triple-pane windows to help insulate the windows. Window World windows use the Intercept™ warm-edge spacer system to provide superior insulation and extend the life of your windows.

4. Sash Lock

This is the locking mechanism that prevents rattling and keeps your windows secure.

5. Lift

The lift is the handle for lifting and lowering the sash.

6. Weatherstripping

Weatherstripping is placed around the window frame and sash wherever two materials meet. It provides another layer of energy efficiency and protection against the elements.

Additional Components of a Window

A window is more than a frame and a pane. Here are some other window part names you should know:

1. Casing

The casing is the molding that goes around the window frames on the exterior of the house. They seal the window frame to the house and prevent outside air from entering your home.

2. Mullion

A mullion is a structural piece that connects two or more windows together.

3. Grilles

Grilles are decorative pieces that give a window the appearance of multiple panes of glass.

4. Fixed Panel

The stationary window pane is referred to as a fixed panel. It is inoperable and is most commonly seen in single-hung windows.

Energy-Efficient Window Terminology

In addition to window parts, the lingo around energy efficiency can be intimidating for the average person. Here is everything you need to know to confidently choose the most energy-efficient window purchase!

1. Low-E Glass

Low-emissivity (low-E) glass is an energy-efficient glass option. Designed to filter the amount of UV light that enters your home, it helps regulate the amount of heat that enters your home. This helps keep your home’s temperatures more consistent.

2. Argon Gas

Argon gas is a colorless, odorless gas used as an insulator in double and triple-pane windows. When paired with Low-E glass, it keeps the window closer to room temperature, helping eliminate drafts and increase energy efficiency.

Upgrade for Premium Window Design

Window World windows are built with you in mind and come with all of the elements that provide unmatched durability, security, curb appeal, and energy efficiency.

If you’re ready to upgrade the windows in your home, make Window World of Long Island your first choice. With a variety of replacement window styles and energy efficiency packages, we have just what you’re looking for. Get started by requesting your free estimate today!