In the Acoustical Ceilings construction sequence, which step is performed last?

• A. Install wall angle around perimeter
• B. One quarter inch pencil rod to underside of deck
• C. Install acoustical tiles
• D. Secure 2 ft or 4 ft cross tees

Answer: (C)

In suspended acoustical ceilings, finishing the ceiling surface comes last. The grid must be in place before tiles are added, so they can be properly supported and aligned. First you set the boundary with the perimeter wall angle, which defines the edges and provides initial support. Then you suspend the grid from the deck using pencil rods (or other hangers) to establish height. After that, you assemble and secure the cross tees and main runners to form the complete grid. Only once this framework is complete do you install the acoustical tiles, which snap into the grid to create the finished ceiling surface.