Free preview · Designing with daylight
Good lighting design starts in daylight, because daylight is free, changing and the standard against which every lamp is judged. Design the daylight first and the artificial scheme becomes a much smaller problem. Think in terms of where light enters and how deep it goes. A side window delivers useful daylight roughly two to two and a half times its head height into the room; beyond that the room is lit by reflection, and a dark floor or dark rear wall will kill it. Raising the window head does more for daylight than widening the window. A high clerestory or a rooflight delivers several times the light of the same area of side glazing and reaches the middle of a plan where side windows cannot. Orientation changes the character as much as the quantity. North light is diffuse and steady, the reason studios and workshops want it. South light is strong and predictable and can be shaded with a horizontal projection sized from the sun angle. East and west bring low, hot, glaring sun that horizontal shades cannot control; use vertical fins, deep reveals, screens or jaalis, or simply put fewer openings there. Reflectance matters as much as aperture. A pale ceiling, a light rear wall and a mid-tone floor can double the perceived brightness of a room without a single extra square metre of glass.