Crown Molding

This is a typical crown molding job. The only obstacle was the vent near the ceiling's edge in the second photo. Since the slope of the ceiling was less than 5 degrees, I decided not to do transition pieces at the corners. If the walls and ceiling are getting painted I always recommend painting before installing the crown for obvious reasons.

I also recommend painting the molding before it goes up. If it is pre-primed wood scuff the surface with a medium steel wool. If the wood is bare use a good primer first before painting a topcoat. I can't overstate enough the importance of using a top quality paint and primer. That also includes the walls and ceiling. Remember that top dollar doesn't automatically translate to top quality. I like to refer to Consumer Reports at least once a year because the manufactures constantly change their formula, which sometimes is not a good thing.

I solved the vent issue by cutting a notch in the crown and filling it in with foam. After the foam dried, I cut it level with the notch. I then used balsa wood to fill in over the foam. It turned out quite nice.

The newly painted wood will get scuffed and dirty in the process of installation, but it is still a lot easier to touch up after the install than to paint from scratch. Touch up is inevitable anyway because of the nail holes that have to be filled in later. Caulk the molding and remove excess with a damp sponge.