What distinguishes a vestibule from other entry points in a building?

A vestibule is distinguished from other entry points in a building primarily due to its connection to the outdoors. A vestibule serves as an intermediary space between the exterior and the interior of a building, helping to create a buffer that can reduce the exchange of heat and air between these two environments. This transitional area can play a crucial role in maintaining energy efficiency by minimizing drafts and controlling temperature fluctuations when doors are opened.

The connection to the outdoors is significant because it allows for controlled access into the main building, enhancing security and privacy while also facilitating a smooth flow of people. Typically, vestibules feature outer and inner doors, which further contribute to their functional purpose as a barrier against external elements.

While size may vary, it's not the defining characteristic, as vestibules can come in different dimensions. Their being used as a waiting area relates to functionality but is not unique to vestibules as other areas in a building can serve similar purposes. Vertical alignment may pertain to architectural design, but it does not specifically define the vestibule's role in connecting spaces and maintaining temperature control.