Question on drywall patch in the ceiling

Question

I have a ceiling vent where the drywall is cut a bit larger than the actual vent. I was looking for some advice on the repair.

The duct is mounted to a stud along the top (a piece of the stud is visible in the top right). Should I cut a slightly larger square (around the vent cover) and add a piece of backing on the bottom side so I have something to screw the patch into on the top/bottom? Or should I cut a larger section of drywall out so I can catch the stud on the bottom. The vent cover itself is about 8 inches.

Answer 1

The best way to make the repair will be to cut a square hole that will catch half of a joist on the top and bottom. Trying to make it work with just one joist isn't a good option for a repair like this that needs to help support a vent.

Carefully cut the vent square in the patch and float the seams as usual to make a finished patch.

Answer 2

I'll assume your joists are 16" oc and the vent is 12". I'll assume this is 5/8" or CD 1/2" drywall for rigidity.

I'll also assume that the vent housing (metal box) is attached both to the joist and likely on the back to some blocking that spans to the other joist making it rigid.

If the box is wobbly then I'd add some more support.

Given the above I'd cut back 4.5" of drywall from the bottom gap to the next center joist. I'd make a U shaped patch and add nailing edges between the joists (can be 1x4). Make the legs of the U patch something reasonable like 4".