lay-in ceiling panels

Unlike ceiling tiles that are glued or stapled to the ceiling, these panels are laid into a modular grid of metal bars, T-shaped in cross section. The grid is supported by wires suspended from the true ceiling and by having its perimeter fastened to the walls.

Panels are typically made of fireproofed fiber and resemble acoustical ceiling tile. However, embossed metal panels ("tin ceilings") are also available.

Panels in the same dimensions are made that contain lighting fixtures (especially fluorescents), loudspeakers, vents for heating and air conditioning ducts, and so on.

Nominal dimensions

1½ feet by 1½ feet
2 feet by 2 feet (cross grid bars are available that make it possible to lay 2' by 2' panels in a 2' by 4' grid)
2 feet by 4 feet (most common size)
4 feet by 4 feet
4 feet by 6 feet

Metric dimensions

500 millimeters by 1500 millimeters
600 mm by 600 mm
600 mm by 1200 mm
600 mm by 1500 mm

UL-94-HF-1