Crown Molding

[George Bokros]

I am back to installing crown in another room. I had some installed by a professional carpenter in my two story foyer because I do not do extension ladders unless absolutely necessary, emergency.

He used backer in some spots and not others. I asked why and he said he uses it only where necessary. This is only 3 3/4" wide crown. I not it is recommended to use backer for the wider sizes, 5" or larger. I would not tell me how he determines where it was necessary, can anyone chime and shed some light on this? I have never used backer on any of the crown I have installed but I have never installed larger then 3 3/4" either.

Thanks

George

[Peter Quinn]

When you are on the walls running parallel with the ceiling joists there may not be much to which you can nail the top of the crown. Depends on how the house was framed and blocked, but there may be just enough framing to screw the sheet rock, not enough to toe nail back into even on a 3 3/4" wide crown. You could do a little exploration with a long finish nail or screw in a blind place to see if there is anything to hit. The blocking can be screwed to the studs or top plates, the crown can be nailed into that. On walls running perpendicular to the ceiling joists I'd usually just find the joists and nail to those, but you might also need blocking in the corners if a little extra reenforcement is required. A few times a straight edge has revealed a less than perfect spot in the ceiling where I felt a few extra nails would be required to pull the crown tight to the sheet rock, and that spot was between two joists, maybe one of the joists was a bit bowed causing a slight valley between it and the next? So a block set back a 1/4" angled the same as the back of the crown can help to "pull in" a molding in a less than perfect situation.

[Dennis McDonaugh]

Ditto what Peter said. I built our house and added 2X4s perpendicular to the ceiling joists on the sides of the room so I could nail the crown to it. Without them you will need a backer to secure the crown to the ceiling. My wife helped support one end of the crown as I fastened one corner and worked my way back toward her. When I got to the corner the crown wouldn't match up right with the other wall. I finally figured out she wasn't holding it at the right spring angle and it was cocked just a little, but by the time you nailed 15 feet it was off quite a bit. We fixed it by making a 1 foot long piece that she could line up the corner with. It went great after that.