What is a Transom Window? Discover the Beauty and Functionality

In architecture, a transom window is a rectangular or semicircular window positioned above a door or another window. It serves both functional and decorative purposes. Let’s explore more about transom windows.

A transom window is a specific type of window that is typically positioned horizontally above a door or another window. It is often used for decorative or functional purposes and has a distinctive placement at the upper part of a wall, dividing the wall space above the door or window.

Here are some key characteristics of transom windows:

  1. Positioning: Transom windows are situated horizontally above doors or windows. They may be fixed or operable, allowing for ventilation.

  2. Decorative Elements: Transom windows are often designed with decorative elements, such as muntins (dividers that create a grid pattern), stained glass, or other architectural details. These decorative features can add aesthetic appeal to both the interior and exterior of a building.

  3. Functionality: While some transom windows are fixed and serve primarily as decorative elements, others can be operable, providing a means for additional ventilation and natural light.

  4. Architectural Styles: Transom windows are commonly found in various architectural styles, including traditional and historic buildings. They were particularly popular in the 19th and early 20th centuries.

  5. Sizes and Shapes: Transom windows come in various sizes and shapes. They can be rectangular, arched, or have other geometric configurations, depending on the architectural style and design preferences.

  6. Historical Significance: Transom windows have historical significance and were often used in buildings with high ceilings to allow light to penetrate deeper into the interior spaces. They were also practical for improving air circulation in times before modern heating and air conditioning systems.

Transom windows continue to be used in contemporary architecture for both aesthetic and functional reasons.

The Function of Transom Windows

Transom windows have historically been used for ventilation. Exterior transom windows placed above front doors allowed air from outside to flow into the house. Interior transom windows would provide airflow throughout the home. Nowadays, most transom windows are fixed and primarily used for adding natural light and enhancing the aesthetics of a space.

Styles of Transom Windows

Transom windows come in various styles, including rectangular, semicircular, and arched. They can be found in traditional, contemporary, and modern architectural designs. The choice of style depends on the overall design concept and personal preferences.

Installation of Transom Windows

Installing a transom window involves framing the opening above the door or window. It requires sufficient space between the top of the door or window and the ceiling or header. Expert craftsmanship is essential to ensure a seamless and secure installation.

Cost of Transom Windows

The cost of transom windows varies depending on factors such as size, style, materials, and installation complexity. Custom-made transom windows may cost more than pre-designed options. It’s advisable to consult with a professional window supplier or contractor to get accurate cost estimates.

Advantages and Disadvantages of Transom Windows


  • Enhance natural light and create an open and airy feel in a space.
  • Add visual interest and architectural detail to a building.
  • Allow light to pass through while maintaining privacy.


  • Require sufficient space above the door or window for installation.
  • May not be suitable for certain architectural styles.
  • Modern transom windows are often fixed and do not offer ventilation.

Transom Windows vs. Mullions

While transom windows are horizontal beams or bars separating a door from a window above it, mullions are vertical structural members dividing two adjacent windows or a window and a fixed panel. Mullions are used to create separate openings, while transom windows are positioned above a single opening. Both elements serve different purposes in architectural design.


What Is The Purpose Of Transom Windows?

Transom windows serve multiple functions. They can provide ventilation when open, allow natural light into a room, and enhance the aesthetic appeal of a space. While older transom windows were typically operable, modern ones are often fixed and used for decorative purposes.

What Is The Disadvantage Of Transom Window?

The disadvantage of transom windows is that they require sufficient space above your door and may not pair well with certain home styles. Modern transom windows are typically fixed and do not provide ventilation. However, they do add natural light and can be used for decorative purposes.

Why Is It Called A Transom?

A transom is a horizontal beam or bar that separates a door from a window above it in architecture. It is also called a transom window, which is the window above this beam. In nautical terms, a transom refers to the back of a boat or a horizontal beam supporting the stern.

What Is The Difference Between A Transom And A Mullion?

A transom is a horizontal beam or bar that separates a door from a window above it. A mullion, on the other hand, is a vertical structural member that divides the glass in a window or door. Transoms are horizontal, while mullions are vertical.

In Conclusion

Transom windows are an elegant architectural feature that adds charm and character to any building. Whether for functional ventilation or aesthetic enhancement, these windows are a versatile addition to homes and commercial spaces. Choose the style and design that best suits your needs and enjoy the beauty and functionality that transom windows bring.

Updated: December 30, 2023 — 11:52 pm