I am about to install tongue and groove planks on a bedroom ceiling, when I realized that the ceiling is severely bowed in the center, it hangs down about 2 inches lower in the center. I went up in the attic to investigate, and I discovered that there’s actually two layers of drywall on the ceiling. The top layer is not sagging at all, and is secured to the joists, but the bottom layer has a gap of about 2 inches in the center.
How can I fix this? I don’t feel like I should just plank over top of the sagging ceiling without fixing it. Would you remove the bottom layer of drywall and then add the planks? I have tried to secure the second layer tighter with screws, but it is really difficult because it pops through the screws. Any ideas? Also have some concerns about safety, I don’t want the ceiling falling on anybody.
New info for anybody wondering: the top layer of drywall is installed upside-down (the finish side toward the attic) and I cut a hole and there is no popcorn ceiling or mold visible. It appears that this was done when the house was built and is likely in the whole house (built 1979).
We tried to raise the ceiling with 2x4 support and screw every 3-5”, but drywal drops and pulls right through the screws as soon as we remove support.
Decided to rip down the bottom layer of drywall and discovered there were NO fasteners used. It was held up by the can lights and sides of the room as the glue had failed. Idk what builders were thinking.