Running Crown on Cathedral Ceilings, continued

Using Transition Pieces

When two pieces of molding — like casing, chair rail, or baseboard — meet at different planes, a triangular transition piece often solves the problem. But that solution for vaulted ceilings never dawned on me until JLC Live presenter Mike Sloggatt suggested it about a year ago at a show. Opinions vary on this technique. Some people think that corner transitions don't look good because of the extra miter in the crown molding at every corner. But I like the technique: The additional lines emphasize the molding profiles, like running three-piece crown around bull-nosed corners or breaking crown around end blocks on a mantelpiece (Figure 4).

Figure 4.When working with a single size of crown, a pie-shaped transition piece, mitered so its bottom edge is level, can make a tight transition between the rake and the horizontal crown.

Before cutting cathedral-ceiling transitions, you first need an understanding of how to cut miters for a gable-end peak. When cutting crown molding in position for standard horizontal runs, the material is always placed in the saw upside down, with the base of the saw representing the ceiling plane. But when cutting gable-end crown, the crown sits in the saw the same way it sits on the wall, right side up.

Understanding that makes cutting the transition pieces much easier. These are basically triangles of molding, with both miters at the top of the transition coming to a sharp point. The miter on the edge that meets the horizontal run is a standard inside corner, which could also be coped. This piece must be placed upside down in the saw and cut at 45 degrees, with the long point against the fence (Figure 5).

Figure 5.When cutting the transition piece, the first cut, made on the edge that meets with the level run of crown molding, is made in upside-down position — a standard inside corner cut (left). The other edge, which mates with the rake crown, is cut right side up (below).

But the miter on the other edge of the pie-shaped transition piece, which meets the raked crown running up the gable, is cut right side up, with the short point against the fence. The angle of the miter is not 45 degrees; in this case, it's 78 degrees, which means you cut at 12 degrees on the miter saw.

Determining the miter angle isn't quite as easy as sticking an angle finder in the corner. In the case shown here, the angle of the wall-ceiling intersection is 114 degrees, but that's not the angle you need to cut. Figure 6, next page, shows a couple of ways to solve this.

Figure 6.To figure the miter angle for the bottom end of the rake molding, the author first measures the ceiling-wall angle (top), then uses basic geometry to solve for the cut angle.

Making the cuts. I cut transitions from short pieces of scrap material, and I make a lot more scraps doing it. But I never use a piece that's too short to hold comfortably — I like my fingers.

Using Pendants

If all those angles and miters are too confusing, pendants might be the right alternative (Figure 7). I like making pendants, and I like the way they look, especially in homes with abundant moldings. But many homeowners (and lots of other carpenters I've heard from) think they look cheesy. Still, I have yet to find a better way to handle an outside corner in a room with a cathedral ceiling.

Figure 7.Pendants can provide a point of termination for crown molding and eliminate the need to join a rake run with a horizontal run (top). The author makes pendants from scraps, mitering four pieces together using spring clamps, glue, and pin nails (bottom).

Pendants are easy to make, and they don't require a lot of molding. I typically make them from the pieces of waste that are left after installing crown in all the easy rooms. The first step is cutting the miters to exactly the same size. I've used a pencil mark on the base of my saw as a stop guide, but clamping a repetitive stop to the extension wing is a more reliable way to ensure that every piece is identical. After assembling the pendants, I make the base blocks 1/4 inch wider than the widest part of the pendant, which provides a perfect reveal line.

For small pendants, I rip down a block of 4x4 until the reveal is right, then cut the block to match the slope of the ceiling. For large crown molding, I make the block from pieces of 1-by with mitered corners.

Outside Corners

When it comes to outside corners that intersect a vaulted ceiling, I draw a blank and install a pendant (Figure 8).

Figure 8.Pendants provide a ready solution for outside corners that interrupt a cathedral ceiling.

The problem I've had is, with the top cut to fit the slope of the ceiling, the horizontal crown molding installs much higher than the raked crown molding. Joining the two in an outside-corner miter has stumped me. If anyone has a solution to this problem, I invite you to share it with me and other readers by writing to the magazine or posting a message on the Finish Carpentry Forum.