What works good for painted crown moulding?

[Brett Nelson]

so here's my long winded rant about current building practices, not aimed entirely at you but your post is the one that got my brain smoking. it's not your fault, after all, you've been duped by shady builders like everyone else.

no offense to you or your sister but seams in the middle of walls and edge butted moldings are not 'high end'. so that isn't the only ride she was taken for . there are alot of modern building practices sold as 'high end' that are absolutely, positively, not. nor is MDF a solution to poor practices and design.

caps or bases that are to join on edge should be in opposing rabbets not butted edge to edge. the cap or base should be toenailed to the rabbet on the piece it is joined to, that way the path of least resistance is into the joint, not away from it. caulk cannot fix this, caulk used for such a thing is a patchwork solution to poor design and fit designed to work until the check clears and not much longer. the only proper use of caulk is to seal edge to wall, and only that because walls aren't plastered anymore like they used to be.

in addition to all of the above, no single run should be longer than the boards you can source. if there's a 35 foot run of wall without a break in the molding it's a badly designed room. that space should be divided by a door, a bay window, a cabinet, something. 'open floor plan' is another modern scam to eliminate doors and moldings and thus build things cheaper. and finger jointed moldings aren't a solution to that. you can't join boards of the same thickness end to end on an unstable substrate and have them stay that way over time, no matter how you cut the ends. if this was possible no one would buy lumber in longer than truck-bed lengths.

also, 15 gauge finish nails are not sufficient to hold such large moldings if the walls aren't perfectly flat. the solution is to use larger, rougher nails or trim screws, and more of them. the conversation would go like... trim 'carpenter': but i can't use my nailgun and can't trim this house in 3 days. i know, i'll give them a long list of excuses about how you "can't do this" and "can't do that" and so forth and so on. your response would be: i get it, you don't like the fact that you can't use your nailgun and you won't be out of here in a week. get over it, or go bid on another job.

there are thousands of examples of centuries+ old buildings in which the moldings are just as snug as they were when they were originally hung and finished. and the people that trimmed those buildings didn't have MDF or caulk, and didn't have nailguns to shoot a room full of moldings onto the wall with in 10 minutes.

they did have..

1) properly designed multi-part moldings that were fit to pull together, rather than pull apart.

2) fasteners sufficient to hold said moldings in place, not a caulk gun full of liquid nails.

3) the time to not just cut/shoot/paint but to back prime/seal every piece before it was hung, thus keeping it more stable through the seasons.

emulating cheap building practices because cheap builders do it isn't a solution to said cheap building practices. demanding better of people and materials is the solution.

but that will cost more!

yes it will cost more. but it will actually be 'high end', not just low end with fatter particle board.



i can't wait either, but i bet i'm going to have to.

that said, vinyl is not a solution either. vinyl expands and contracts with temperature changes more than wood does with moisture changes. the only person that vinyl benefits is the builder, one less contractor (no paint).

I understand your rant, and agree with most of it. But I take exception to certain points.

One is to point out that I live in UT. -30*F in the winter and 105*F... we usually sit at about 15% RH until a storm system moves in at which point we hit 100%RH for a week or two at a time.

Needless to say that wood doesn't perform well here. The finely crafted older building are subject to the same cracking and gaps that the newer buildings are. The modern solution to that problem is more paint and caulk.

When I stated that my sisters seams have all cracked out, I was not referring to scarf joints. I was referring to seem where the crown meets the wall and the ceiling. Plaster or not, these will crack out. I agree with your point about modern building not assembling profiles correctly. One reason they didn't see the separation of the moulding from the wall is because they weren't that excited about 8" wide coves. Unless you mill that trim from heart wood, there is no way that it is going to be stable. That is why I assembled my crown the way that I did. It is historically correct, but they did it that way because it was both functional and more dimensionally stable. I made a conscious decision to use MDF in certain areas, because I was willing to make the compromise. I don't consider my home high-end, but rather a well built middle class home.

I guess my point is that different environments demand different practices. Not an excuse for poor building practices, but rather a suggestion that modern materials and building practices are not always inferior, but are sometimes born out of necessity. Glues and fasteners have only gotten better in time. Unfortunately, that has spurred builders to use less of them.