Pavilions may be small garden outbuildings, similar to a summer house or a kiosk; small rooms on the roof of a large house, reached only via the roof (rather than by internal stairs) may also be called pavilions. These were particularly popular up to the 18th century and can be equated to the Italian casina, formerly rendered in English « casino ». These often resembled small classical temples and follies. Especially if there is some space for food preparation, they may be called a banqueting house. A pavilion built to take advantage of a view may be referred to as a gazebo. Bandstands in a park are a class of pavilion. A pool house by a swimming pool may have sufficient character and charm to be called a pavilion. By contrast, a free-standing pavilion can also be a far larger building such as the Royal Pavilion at Brighton, which is in fact a large oriental style palace; however, like its smaller namesakes, the common factor is that it was built for pleasure and relaxation.
A sports pavilion is usually a building adjacent to a sports ground used for changing clothes and often partaking of refreshments. Often it has a verandah to provide protection from the sun for spectators. In cricket grounds, as at Lords, a cricket pavilion tends to be used for the building the players emerge from and return to, even when this is actually a large building including a grandstand. The term pavilion can also be used in stadia, especially baseball parks, to distinguish a typically single-decked, covered seating area from the more expensive seating area of the main grandstand and the less expensive seating area of the uncovered bleachers.
Externally, pavilions may be emphasised by any combination of a change in height, profile (a flat facade may end in round pavilions, or flat ones that project out), colour, material, and ornament. Internally they may be part of a rectangular block, or only connected to the main block by a thin section of building. The two 18th-century English country houses of Houghton Hall and Holkham Hall, illustrate these different approaches in turn.
In the Place des Vosges, Paris (1605–12), twin pavilions mark the centers of the north and south sides of the square (illustration, lower). They are named the Pavillon du Roi and the Pavillon de la Reine though no royal personage ever lived in the square. With their triple archways, they function like gatehouses that give access to the privileged space of the square. French gatehouses had been built in the form of such pavilions in the preceding century.