Engawa

In Japanese architecture, an engawa (縁側 or 掾側) or en (縁) is an edging strip of non-tatami-matted flooring, usually wood or bamboo. The ens may run around the rooms, on the outside of the building, in which case they resembles a porch or sunroom.

Usually, the en is outside the translucent paper shōji, but inside the (雨戸) storm shutters (when they are not packed away). However, some en run outside the amados. Ens that cannot be enclosed by amados, or sufficiently sheltered by eaves, must be finished to withstand the Japanese climate. Modern architecture often encloses an en with sheet glass. An engawa allows the building to remain open in the rain or sun, without getting too wet or hot, and allows flexible ventilation and sightlines.

The area under an engawa is sloped away from the building, and often paved, to carry the water away. The area directly outside the paving is usually a collector drain that takes water still further away. The engawa is thus a way to bridge the obstacles good drainage puts between the indoors and the outdoors.

En means an edge; gawa a side. The terms en and engawa were historically used interchangeably, but engawa now generally refers to the veranda directly outside the shutters. Types of en include:

If there are fewer than three ens, an en may be described by more than one of the positional terms.

Kirime-en showing traditional mitered corner treatment; if it continues all around the building, it is also a mawari-en. Sunoko-en in foreground.

Kure-en. The gravel path may well double as a collector drain.

The core of a traditional building is the innermost room or moya (母屋) (see diagram). This is surrounded by the hisashi (廂,庇), which is on the same level, and is usually inside the windows and amado (雨戸) storm shutters. The hisashi is often a ring of tatami-floored rooms, but may be an unmatted en; see also hirobisashi (広廂,広庇, 弘廂). In a large building, there may be further layers of tatami-floored rooms, courtyards, and further floorplan complications.

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