Txoko # 27: The outdoor room

An outdoor space becomes a special outdoor room when it is well enclosed with walls of the building, walls of foliage, columns, trellis and sky.

Build a place outdoors, which has so much enclosure round it, that it takes on the feeling of a room, even though it is open to the sky. To do this, define it at the corners with columns, perhaps roof it partially with a trellis or sliding canvas roof, and create "walls" around it, with fences, sitting walls, screen hedges, or the exterior walls of the building itself.

Christopher Alexander, 163. Outdoor room in A Pattern of Languuage, pp. 164-168, Oxford University Press, 1967.