Pediment

Pediments are a form of gable in classical architecture, usually of a triangular shape. Pediments are placed above the horizontal structure of the cornice (an elaborated lintel), or entablature if supported by columns. In ancient architecture, a wide and low triangular pediment (the side angles 12.5° to 16°) typically formed the top element of the portico of a Greek temple, a style continued in Roman temples. But large pediments were rare on other types of building before Renaissance architecture. For symmetric designs, it provides a center point and is often used to add grandness to entrances.

The cornice continues round the top of the pediment, as well as below it; the rising sides are often called the "raking cornice". The tympanum is the triangular area within the pediment, which is often decorated with a pedimental sculpture which may be freestanding or a relief sculpture. The tympanum may hold an inscription, or in modern times, a clock face.

The main variant shapes are the "segmental", "curved", or "arch" pediment, where the straight line triangle of the cornice is replaced by a curve making a segment of a circle, the broken pediment where the cornice has a gap at the apex, and the open pediment, with a gap in the cornice along the base. Both triangular and segmental pediments can have "broken" and "open" forms.

Pediments are found in ancient Greek architecture as early as 580 BC, in the archaic Temple of Artemis, Corfu, which was probably one of the first. Pediments return in Renaissance architecture and are then much used in later styles such as Baroque, Neoclassical, and Beaux-Arts architecture, which favoured the segmental variant.