I'm looking to add a closet to a room in my house. I took down the walls (and have since had drywall put back up) so I know where the studs are in the walls, but I don't know where the ceiling joists are. I don't have access to them from above since there are hardwood floors upstairs.
I'm not sure how I should go about attaching the top plates for the closet. Can I just screw them into the lath? Will this crush the plaster and cause everything to come crashing down? Should I (and how would I?) remove the plaster above the closet so I can see the joists? What if the closet walls line up with the wall studs, but the ceiling joists don't?