What is a window jamb?

A window jamb is the vertical part of a window frame that forms the sides of the window opening. It is typically made of wood, metal, or vinyl and helps to support the weight of the window and keep it secure within the wall. The jamb also helps to seal the window opening, preventing air leakage and water infiltration.

Window jambs can be single or double depending on the type of window and can be customized to fit different wall thicknesses. They are an important component of the window frame and are essential for the proper installation and function of the window. In addition to supporting the window, jambs also provide a finished appearance to the window opening.