Overheng

Overheng is a term used in several disciplines to describe a projection that extends beyond its supporting edge. In architecture and building construction, an overhang refers to any portion of a structure that protrudes horizontally beyond the underlying wall or foundation, such as roof eaves, canopies, balconies, or cantilevered elements. Overhangs help provide weather protection, shade, and architectural variety, and their design involves structural considerations for load transfer, deflection, drainage, and safety.

In civil engineering and urban planning, overhangs are designed with attention to the constraints of the building frame, wind loads, snow loads, and local codes. Distinctions are often made between simple overhangs and cantilevers, where the latter rely on a continuous support at one end and exhibit different bending moments.

In geology and geomorphology, an overhang describes a rock or cliff that projects beyond the face below, typically formed by erosion, differential weathering, or glacial action. Such features can be indicators of past environmental conditions and may be subject to instability or failure under weathering, earthquakes, or heavy precipitation.

In all contexts, the term denotes a projection resulting from design choice or natural processes, and its use is shaped by material properties, environmental conditions, and safety considerations. See also: cantilever, eave, balcony, rock overhang.