Fitting Trim to a Badly Plastered Ceiling

Tips and tricks for a funky ceiling trim job. March 25, 2008

Share some wisdom... I am soon to be installing a 6+" crown molding in a large room where the 9' high ceiling (which was feframed/blueboard/plaster a couple years ago) has a really poor plaster job with lumps and bumps, and nothing is straight, flat, or level. The wall framing/plaster is equally dynamic! I have 10' and 12' pieces, the longest wall is 20', and the quartersawn molding is thick, heavy, bulletproof, and inflexible, having been milled from 5/4". I've installed plenty of crown, but this is intimidating. Any tricks?

Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor L:
If this works into the look that you are trying to achieve, you can do it. Wrap the room with flat stock on the walls and ceiling (where the crown is going) and have a thumbnail or a cove on the edge. Use shimming to keep everything as flat as you can. It will be more costly in materials (and labor), and the client should pay if they expect a decent job with a lousy base.

From contributor J:
As I was reading your post, I was thinking the same thing as contributor L. Assure the homeowner it is the best way to go. When it's all done, I'm sure the homeowner will like the 2 or 3 piece crown. Depending on how bad the walls and ceilings are, you or a painter could tint some caulking (I know, it's a bad word) to match the finish of the crown and that should make minor irregularities disappear.

From contributor T:
Do a little mockup of what contributor L is saying and also hold a piece of the crown up against the ceiling where the bump is biggest. An informed homeowner can be your friend then.

I have a taper/spackler buddy who is great with a wide knife who smoothed out the bumps in my own 1927 plastered house before I installed my crown. Find one by you?

As contributor J says, caulk. We call it Prairie Caulk - for them wide open spaces.

From contributor V:
I really prefer the idea of having the plaster repaired. It's especially easy if you put up a ledger piece first, because the plasterer can just bring plaster up to it, then you can add a small detail piece.