Vestibule (architecture)

A vestibule /ˈvɛstᵻbjuːl/ is an anteroom (antechamber) or small foyer leading into a larger space, such as a lobby, entrance hall, passage, etc., for the purpose of waiting, withholding the larger space view, reducing heat loss, providing space for outwear, etc. The term applies to structures in both modern and historical architecture since ancient times. In modern architecture, vestibule typically refers to a small room next to the outer door and connecting it with the interior of the building. In ancient Roman architecture, vestibule (Latin: vestibulum) referred to a partially enclosed area between the interior of the house and the street.

In contemporary usage, a vestibule constitutes an area surrounding the exterior door. It acts as an antechamber between the exterior and the interior structure. Often it connects the doorway to a lobby or hallway. It is the space one occupies once passing the door, but not yet in the main interior of the building.

Although vestibules are common in private residences, as a modified mud room, they are especially prevalent in more opulent buildings, such as government ones, designed to elicit a sense of grandeur by contrasting the vestibule's small space with the following greater one, and by adding the aspect of anticipation. The residence of the White House in the United States is such an example, but somewhat confusing. At the north portico, it contains a tiny vestibule now between the doors flushed with the outer and inner faces of the exterior wall of, and in the past inside, the Entrance Hall (called incorrectly Vestibule) separated from the not much bigger Cross Hall by just 2 double columns. The difference in sizes between a vestibule and the following space is better illustrated by the - so called - entrance (15) to the main gallery in the Solomon R. Guggenheim Museum by Frank Lloyd Wright. Many government buildings mimic the classical architecture from which the vestibule originates.

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