Project Difficulty:
Moderate Estimated
Project Time: 4 hours or more
Tools and Materials:
Circular saw
Drill
Hammer
Caulking gun
Construction adhesive
Chalk-line box
Measuring tape
Safety goggles
Pencil
Floor jack (optional)
2x6 strongback
2x4 crossbracing
2x4 or 4x4 post for jacking the ceiling
2x10 or 2x12 scrap board
Wood screws or nails
There are several steps you can take to raise a sagging ceiling. However, if the sagging is widespread, you probably should have the framing inspected by a contractor, architect, or structural engineer.
The framing could be inadequate, as often is the case in newly finished attics where the old joists were not sized to bear the weight of furniture and people.
However, you can probably remove the sag from one or two joists by following the procedure below.
1.
Wedge a Wide Board against the Ceiling
Use a wide board to protect the ceiling by distributing the force of the post that was wedged or jacked from below to raise the sag. (Fig. 1)
2.
Mark the Center of the Sag
Go to the level above the sag (the attic in this example) and snap a chalk line across the joists down the center of the sagging area.
Use the chalk line as a guide for affixing the lower part of the strongback (in the next step). (Fig. 2)
3.
Cross the Sag with a 2x4
Position a 2x4 across the sagging joists at the chalk line.
Add a bead of construction adhesive at the laps; then screw the 2x4 to the joists. (Fig. 3)
4.
Add Construction Adhesive
To prepare the strongback connection, add more construction adhesive along the entire edge of the newly installed 2x4. (Fig. 4)
5.
Affix a Perpendicular 2x6
Set a 2x6 with a natural crown (upward bow) perpendicularly against the 2x4. Screw it obliquely through the 2x4 and into each joist. (Fig. 5)