A troffer light is a drop ceiling light fixture placed in the grid opening of a T-bar structure. Drop ceilings are suspended mechanical ceilings installed under the original ceiling of a building. They provide a false or secondary ceiling that fulfills many functions difficult to achieve with an exposed ceiling solution or other types of ceiling construction. A typical drop ceiling system consists of a metal framework which runs in a grid pattern across the room. The metal framework is built with T-bar rails on which ceiling tiles rest to create a concealed space for hiding HVAC ducts, electrical conduit, plumbing lines, and the original ceiling. The T-bar grid is also used to accommodate lighting fixtures, fire detection devices, air grilles and diffusers, security cameras and sound systems.
Because of their clean aesthetics as well as their modular flexibility to integrate the functions of lighting, air distribution, acoustical control, thermal insulation and fire protection, suspended ceilings become a staple of modern construction and architecture in commercial and even residential applications. Grid ceiling systems are commonly found in offices, schools, libraries, retail spaces, hospitals, healthcare facilities, etc. This popularity is accompanied by the widespread use of troffer lights which are either laid into the metal grid from above the ceiling or clipped into position from below the ceiling. A drop ceiling provides a grid of square or rectangular openings, into which ceiling tiles and troffer lights are set to produce a finished ceiling for a space.