Things You'll Need
16-gauge hanger wire
Installing a suspended ceiling involves connecting a grid at a specific level to support the tiles that make up the ceiling surface. The grid hangs from a higher ceiling or from beams crossing the room, with the assistance of carefully measured and placed hanger wire, and metal molding on the wall. Changing the levels in a suspended ceiling requires that you change the levels of the molding and the wire. It requires the complete disassembly of the ceiling, adjustment of wire length or replacement of the wires, and moving the molding. The project may take longer than the original installation, but when you're through, the ceiling will be at the height you want.
Determine the new height for your suspended ceiling. Check local building codes for minimum height restrictions before proceeding. Leave space above the grid for installing tiles -- 4 inches for tile alone, 6 inches for tiles with light fixtures.
Place a series of marks around the circumference of the room at the desired level. Use a carpenter's level to make sure that the marks are level.
Snap lines of chalk on the walls at the new level. Extend the chalk string between adjacent marks. Lift the string from the wall slightly and then let it go, snapping it against the wall and leaving a straight line of chalk.
Remove the tiles from the gridwork. Push the tile at the corner, tilt it at a diagonal angle to the grid hole and slip the tile through the grid. Place it to the side.
Disassemble the gridwork. Remove the T strips -- the small strips between the longer grid runners extending the length of the room -- by lifting them from the runners. Remove the runners by uncoiling the wire suspended from the ceiling that holds them in place. Then lift them from the wall-mounted metal molding running around the room. Set the gridwork aside.
Move the molding to the new ceiling level marked by the chalk. Remove the nails holding the molding in place, then move the molding to the new level. Nail the molding back in place, attaching it to wall studs using 6d nails. You can locate the wall studs using the stud finder.
Adjust the length of the hanger wire. Snip the wire with tin snips if moving the ceiling upward. Extend the wire, if possible, to lower the ceiling. Replace the wire if it isn't long enough. Remove the old wire from the ceiling joists. Tie new wire in its place in the existing wire hanger screws attached to the joists. Make the wire long enough to run past the level of the new gridwork by 6 inches.
Rebuild the grid. Attach the runners to the wires by bending the wires at grid level and running them through the holes on the runners. Mount the runners to the molding and replace the cross Ts to make the squares that hold the tile.
Replace the tile in the gridwork by slipping the tiles through the grid holes, then settling them into place. The edges of the tiles should contain grooves that run along the gridwork, holding them steady after you place them.