Clerestory Windows, Sawtooth Roofs

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When dealing with lighting, there are several ways to get more natural light into a building. Christopher Alexander has several different approaches, including south-facing entrances, light on two sides, half-open walls, solid doors with glass, pools of light, indoor sunlight, and wings of light.

Two patterns that are not present in A Pattern Language (largely because of his rather limited design of roofs) but definitely are worth considering are clerestory windows and sawtooth roofs.

Both of these allow light to come from or just under the ceiling. These do not add additional views, but lighten the ceiling and interior of buildings in significant, energy-saving ways.

Sawtooth Roofs

The Sawtooth Building in Berkeley, California is one example, but there were many built with this design, as passive lighting was the only option until electric lighting became possible.

> Before electric light substituted for daylight in the late 19th century, consideration of good daylight strategies was essential. The sawtooth roof, with its glass panels facing away from the equator, blocks the light and heat of direct sun exposure and provides uniform, natural light over a large area. It was particularly useful in design factories and manufacturing buildings. > > Sawtooth structures show apertures with vertical or angled glazing installed in a sloped roof plane. Sawtooths are most effective when used in series of three, and were historically used in industrial and manufacturing buildings as the primary light source.1

Clerestory Windows

While as above, Sawtooth roofs are sometimes called clerestory windows, the term is much broader and encompasses a wide variety of windows which are above eye level.

Clerestory windows can even be open-air and use reflective exerior walls.


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