Lintels are horizontal beams that offer load bearing support across a space between two vertical points, such as over a window, door or fireplace. The lintel supports the weight of the masonry above.

Typically, lintels are made from concrete or steel, although older properties may have wooden lintels. In older properties with wooden-framed windows, the lintel can be built into the window itself. Modern lintels can be fully insulated to reduce thermal bridging.