Flush-mount lights are mounted directly against the ceiling, so that light spreads out in a downward cone. The light fixture’s upper edges meet up with the ceiling, which is why they are described as flush. With a semiflush mount light fixture, the light is generally 1 to 3 inches below ceiling level with only a limited portion of the edge level or even with the ceiling.
A common semiflush-mount fixture style has one or more stems holding a glass panel or half-globe a few inches below the ceiling. The light bulbs rest above the panel or inside the half-globe a short distance away from the ceiling. This fixture type is not quite flush because its edges do not rest evenly with the ceiling, but not dropped far below the ceiling level, so it is semiflush.
Semiflush-mount lights give more indirect light than a comparable wattage flush-mount fixture. Indirect light is light reflected from another surface before reaching you or the objects in the room. Light that shines up toward the ceiling from semiflush-mount fixtures give a room a brighter feel, thanks to this indirect lighting, particularly if the ceiling is white or light-colored so it reflects more of the light back into the room.
Semiflush fixtures are best for general lighting in rooms, such as kitchens, living rooms and dens. They are used in bathrooms as supplemental lighting, but do not provide the best light for personal grooming due to the light’s angle. For bathroom mirror areas, supplement a semiflush fixture with vanity lights, which usually hang from the wall above the mirror. Semiflush fixtures provide adequate general lighting for bedrooms, but supplementing them with bedside desk lamps or other less general lighting creates a more relaxing atmosphere.