Shape the space between buildings as carefully as the rooms: make outdoor spaces partly enclosed and convex, like outdoor rooms, rather than leftover gaps around freestanding objects.
Rules · Light · Plans · Doors & windows
Light on two sides of every room
Give every room in which people spend time daylight from at least two sides; plan the building in narrow wings so that this is possible.
Alexander and his colleagues argue that rooms lit from one side only are gloomy and full of glare, because the bright window is seen against dark walls; light from two directions softens shadows, shows faces clearly and makes a room feel pleasant. The pattern has consequences for the whole building: wings no more than about 6–8 m deep, many corners, and plans that wrap around courts rather than fat, deep blocks.
Wright’s Prairie houses, with their narrow cruciform wings and bands of windows on both sides, satisfy the pattern almost everywhere; so do the through-flats of the Unité d’habitation, which run from one façade to the other.
Related rules
On an equator-facing window, make the overhang deep enough to shade the whole window from the high noon sun of summer, and no deeper, so that the low winter sun passes beneath it into the room.
noon sun altitude = 90° − latitude ± 23.44° · overhang D = window height ⁄ tan(summer altitude)
Give each room the aspect that suits the hours it is used: the drawing room to the south-east, the morning room to the east, the library a little east of south-east, the dining room to the north or north-east, cool and out of the evening sun, and the kitchen and offices to the north; the best aspect of all is south-east, the worst south-west.
Let the principal room of the front stand out in a bay window, canted or square, under its own gable: more light, a view along the street as well as across it, and a front that shows where the best room is.
Make the hall, not a passage, but the house’s largest and most used room: a great fire with a seat beside it, the other rooms opening off it, and the stair kept out of it or enclosed, so that it does not make the hall a thoroughfare.
Turn the house to the sun rather than to the street: the living rooms on the sunny side, lit from more than one direction, the kitchen and stores on the cool side, and the fewer and larger rooms the better.
Cite this page Chris Paton, “Light on two sides of every room”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/light-on-two-sides. Text, drawings and models licensed under CC BY-NC 4.0.