A light shelf is a horizontal shelf-like light reflector, which can be mounted inside or outside of a window. It helps reflect daylight into areas that are farther away from a window, and also helps to make this daylight less direct and more diffuse. Although mostly used for commercial buildings, light shelves could potentially be suitable for homes, especially for large spaces like family rooms. Light shelves are placed at least seven feet above the ground. This is to prevent having light reflected right into your eyes, and to make sure you don’t bump your head. Light shelves can be used with regular windows, but are also useful below skylights and clerestories. By diffusing the light they reflect, light shelves help to reduce glare. Although the shelves are normally a metal material like aluminum, the rougher and less mirror-like the surface of the shelf, the more diffuse and pleasant the light becomes. Experimentation with other light shelf material has included frosted glass, which helps bounce the light while allowing some light through it.
If made from metal, light shelves are thermal conductors, and could possibly aid in transferring heat and cold through windows into your home. This is a problem for our climate where most of the year’s weather is extremely hot. But with more experimentation and innovative thinking, light shelves may become a great feature for bringing in daylight into your home.