Word-of-the-Month: Transom


A transom is a horizontal structural beam that separates doors and windows. The crosspieces are typically made out of wood or stone. The uniquely-located window above a doorframe is called a ‘transom light.’

Transom lights are common features found in old offices and historic buildings. The open-latch designs increase light and ventilation naturally—a simple solution before the invention of modern utilities. Transom lights offer privacy, as they are located above the door, while letting light into a space.

Today, transoms are often used as decorative pieces to customize or distinguish an architectural detail. Added windows are an aesthetic luxury—showcasing ‘million dollar’ views of local skylines and landscapes.

Fun Fact The opposite of a transom is a mullion. A mullion is a vertical structural beam that separates doors and windows. They are common in modern designs.


Left: A historic original from the former Federal Post Office is now a vintage feature after the demolition and conversion to a Hyatt Place within the Custom House in St. Paul, MN. Right: Hyland Hills Chalet in Bloomington, MN.