I just did exactly that although I was lucky bc furring strips were already in place from acoustical tile ceiling.

Be sure furring strips attach to joists (w screws long enough to go thru plaster & lath). Check with level to make sure you ceiling is reasonably level and flat, If not shim the furing stirps to get them level so ceiling is a flat plane otherwise you might have trouble getting the beadboard in place.

You'll need more strips than just along the perimeter-- Id go every foot or so. Attach beadboard perpendicular to the furring strips. If you just have strips around perimeter and nail the beadboard at the ends it will sag over time.

I'm about to do the same in our kitchen...don't feel like dealing with all the mini hairline cracks in the ceiling...plus, there's texture & old adhesive (yes, on the ceiling)....

The ceiling isn't level...it's lowest point is somewhere in the middle with a 1/2" slope(+\-) going to the east & to the west....any advice?

This is a 1900 vernacular....I thought the beadboard would be both charming & appropriate....I intend on using the t&g style beadboard....

Depending on the plaster substrate (wood or metal lath) nailing could separate the plaster from the lath.

I would not recommend putting wood paneling on a bathroom ceiling even if it is painted with several coats of vapor barrier paint and well ventilated. Why not use drywall or better yet veneer plaster on blueboard (if it is available in your area)?

As you state it's "teeny" it also has an open porch above it, so it needs to be insulated. My idea is to bite the bullet and pull down the plaster, then insulate the exterior roof space and don't forget to add a vapor barrier, and then you can put up anything you wish. Plaster that has been compromised by water is going to continue to slough off particles of various sizes, which will just collect above the beadboard and perhaps filter through the T&G joints as a fine dust forever. So do the plastic vapor barrier at the very least.
Casey

This is an old thread that BMace has used to post a new question. But maybe the answers still apply.

Karin L