Light shelves are an effective way to enhance the lighting from windows on the equator-facing side of a structure, this effect being obtained by placing a white or reflective metal light shelf outside the window. Usually the window will be protected from direct summer season sun by a projecting eave. The light shelf projects beyond the shadow created by the eave and reflects sunlight upward to illuminate the ceiling. This reflected light can contain little heat content and the reflective illumination from the ceiling will typically reduce deep shadows, reducing the need for general illumination.
In the cold winter, a natural light shelf is created when there is snow on the ground which makes it reflective. Low winter sun (see Sun path) reflects off the snow and increases solar gain through equator-facing glass by one-to-two thirds which brightly lights the ceiling of these rooms. Glare control (drapes) may be required.
Read more about this topic: Daylighting
Famous quotes containing the words light and/or shelves:
“Come, and trip it as ye go
On the light fantastic toe,
And in thy right hand lead with thee,
The mountain nymph, sweet Liberty;”
—John Milton (1608–1674)
“The bells discuss the hour’s gradations,
Dusty shelves hold prayers and proofs:
Above, Chaldean constellations
Sparkle over crowded roofs.”
—Philip Larkin (1922–1986)