Mercury lamps are less efficient than metal halide lamps and are almost as poor for color as high-pressure sodium. These three HID lamps warm up a few minutes before reaching full intensity and require special ballasts. Solar-powered landscape and walk lighting requires no wiring for power and installs easily. Floodlights mounted high on buildings provide wider light distribution. Poorly aimed floodlights aimed at windows can disturb residents, neighbors, and others in or near the space.
Covered porches are typical of locations providing enough shelter for damp-location luminaires.
Controls Controls provide lighting flexibility and reduce energy costs. Switches Children or people in wheel chairs can more easily reach switches installed less than 4 feet from the floor. Switches installed under 4 feet are also under the drywall seam. Room entrances make convenient locations for switches. If a luminaire cannot be seen from a switch location, such as an exterior light or basement light controlled from the top of an enclosed stair, a switch with a small indicator light warns that the light has been left on.