Usually a ceiling is just a nice covering of the bottom of the next floor up. A drop ceiling, however, is lower than the bottom of the upper floor.
There are different reasons for making a drop ceiling. Some home improvement people put a drop ceiling in the basement so it's below the pipes, ducts, etc. Other home improvement people may have a 10' ceiling in an old house and want to drop it down. It's very common in a bathroom to put in a drop ceiling if the house is built with a 10' ceiling.
To drop the height of a ceiling down, follow this home improvement procedure. Nail 2x4's as a ribbon around the perimeter walls, nailed into the studs. The bottom of the 2x4's—plus any drywall or other home improvement finishing material—would be the new height of your ceiling.
Go to the longer dimension wall, the wall along the length of the room, and layout on the ribbon on each long wall, 2x4's spaced apart by 16 inches on center (O.C.), so the 2x4's span across the width of the room. You can use joist hangers here but only nail them on one side for now. Don't install the 2x4's yet. Just mark on the ribbon where they will go.
Make up a double 2x4 beam ('strongback') the length of the long wall. Stagger the joints—if any—and place this strongback above and resting on the 2x4 ribbon so the strongback runs down the center of the length of the room. This strongback will go across the row of 2x4's in the center of their span.
The strongback should be on edge and supported from the original ceiling by the same wire that is designed to support a tee bar drop ceiling—a #9 wire. Use eye screws on the top ceiling, securely fastened to the ceiling joists. Wrap the bottom of the wire around the strongback and twist it back around the vertical section of wire. Place these wires no more than 5 feet apart. So for a 13' span, for example, have 2 wires supporting the strongback, evenly spaced from the walls.
Now, install the 2x4's going from the ribbon on one side wall to the ribbon on the opposite wall. Place one end in the joist hanger, then lift the other end up and place it against the ribbon on the opposite wall, not resting on top of it. Toe nail these 2x4's into the ribbon, then place and nail the joist hanger around it. After all the cross members are nailed in place with their joist hangers in position, install the common hurricane tie to the junction between the joists and the strongback. Alternate this tie from side to side on the strongback to the joist. This tie is illustrated here: (see it on Amazon.com)
Dave(Ask Dave) (About Dave)
Hi, I'm Dave Osborne. With over 50 years experience as a journeyman carpenter, foreman and contractor in heavy construction I enjoyed working with apprentices and sharing the tricks of the trade that others shared with me. Now I get emails from Members all over the world and we include many of my answers in our Free Monthly Newsletters. Some of my answers include drawings and instructions specific to a project, but may also answer your questions. I use correct construction terminology, so you can confidently inform your building supply dealers or contractors exactly what you need.
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