Crown Molding Installation Question

[Pat Moy]

I am trying to install crown molding onto a ceiling that's not level. The ceiling has a gradual slope towards one direction. I want to do a two-piece crown, where an inverted baseboard is nailed flat onto the wall, and the crown molding itself nailed onto that and the ceiling. If I level the inverted baseboard and flush the top of the crown molding against the ceiling, then the reveal between the bottom of the crown molding and bottom of the inverted baseboard would be uneven. If I level both the crown molding and inverted baseboard, then I would have a big gap between the ceiling and top of the crown molding on one side. The gap is too big to be filled by calk, or eliminated by scribing the crown molding.

Does anyone know what the standard technique for handling this situation? Thanks in advance for anyone's help.

[Karl Brogger]

Use a piece of the crown you will use to set the height of the 1 stage. Check ahead for oddities in the ceiling. You'll just end up following the slope of the ceiling. You can also just use a spacer to set where the base moulding will land relative to the ceiling.

[Leo Graywacz]

You have a few choices. You could shim out the ceiling and re rock it and then put up your crown. You could put a box that went from the ceiling to the wall, slightly deeper than the crown comes out from the wall, scribe it to the ceiling so that it levels out. Or just do it the simple way and follow the ceiling, scribing slightly where necessary and filling in gaps with caulk [if paint grade molding].

[Pat Moy]

Just want to make sure I've understood the replies correctly. Sounds like the easiest thing to do is to follow the ceiling with my two pieces. Basically, using this approach, neither the inverted baseboard nor the crown molding will be installed level. Is this correct?

[Kelly C. Hanna]

That's what I do when I install crown in oild houses...just follow the ceiling.

[Andrew Minear]

In my experience, the correct way to handle this is to skim the ceiling with drywall compound. Bring it out a couple of feet and feather the edge. Check it with a straight edge. The variance should not be too visible after painting and you have an even surface for your crown. Good luck.

[Todd Crawford]

That is going to be a lot of mud if the difference is so much that he can't scribe or caulk. I would follow the ceiling.

[Karl Brogger]

How out of level are we talking here? How much fall, in how many feet?

How tall is the ceiling? Doesn't matter for putting up the crown, but the higher the ceiling the less noticable.

[Mike Hess]

I would generally just follow the ceiling. I'd consider using a skim coat to lower localized high points that would result in gaps, but if it's an even slope, I'd just follow right along.

The eye will never be able to tell that it's slightly out of level (most surfaces in an old house are somewhat out of level/plumb/square/straight), but you'll see it instantly if there's a gap, or if the reveal on the baseboard is different from one end to the other.

[Pat Moy]

Answering Karl's question: the ceiling is around 9' high; fall is around 1" over a 7' length.

This is actually the crown molding that goes on top of a built-in floor-to-ceiling bookcase. The top of the bookcase measures around 4" from the high point of the ceiling. This gap needs to be covered with the crown molding. The bookcase is level, which is why I'm concern about reveals if I follow the ceiling with the crown molding.

[Karl Brogger]

Best way to handle that is to cheat the base that you're using a bit and split the difference. 1" over 84" isn't too bad, but not that great either. If the base has plenty of flat area to it, hold it down as far as possible too. The difference won't be as noticable that way.

[Pat Moy]

Thanks Karl. I think that's what I'll do.