Install Crown Molding: Cathedral / Vaulted Ceiling .

Take a close look at the above picture of a typical cathedral ceiling. Details are on page 42 in our new 2nd edition book.

Joint "A" is a standard inside corner. The horizontal turn crown slope angle for joint "A" is 52 deg. (Joint "A" is a horizontal turn of the crown molding)

Measure the angle between the adjacent walls in the corner with your True Angle Tool and, using the Crown Molding & Trim book, Compound Miter Chart, Crown Molding Table or the Excel Program, look up the miter and blade tilt to cut the crown molding. Use your crown molding templates to make sure you have set up you saw correctly.

This is the left-hand piece, inside corner, horizontal turn that will go in the corner at joint "A".

For and inside corner horizontal turn you will always be able to see the saw cut and the pointed end will always be at the bottom of the crown molding.

Cut the mating right-hand piece using the same saw settings. This is the crown moulding that goes from joint "A" to "B".

Now this is where it gets a little tricky.

Joint "B" is an outside corner, vertical turn. (The crown turns up and continues on to joint "C".)

Read more here:
Install Crown Molding: Cathedral / Vaulted Ceiling .