The window has been a source of particular concern to energy researchers because of its potential for large heat gains and losses. As a result, many designers have explored ways of controlling or managing energy-related characteristics of windows, while preserving their thermal, lighting and psychological benefits. Among the techniques suggested for improving window performance are the use of: (1) appropriate sizes for windows, (2) window coatings to absorb or reflect energy, and (3) shading devices, both internal and external.

In conjunction with a research program monitoring energy use at the National Bureau of Standards (NBS) in Gaithersburg, Maryland, a study of the use of internal shading devices was undertaken.

Although many suggestions for energy conservation in buildings require the occupant to participate actively in the process, little information is available on the degree or kind of participation currently practiced, even on a matter as simple as the use or management of shading devices at the window.