How Do You Install Crown Molding on a Horizontal Ceiling?

Crown Molding made easy. We have taken all of the guess work out of cutting crown molding. Chapter 4 in our new 2nd edition book deals with installing crown molding on a horizontal ceiling.

In today's modern construction, corners are often built at unusual angles. For example, if you measure a corner angle of 146° and were using crown molding with a spring angle of 38°, you would just simply look up the miter and blade tilt in Chapter 4 or the crown molding table, page 124 thru 141. You would set your compound miter saw for a miter of 10.7° and a blade tilt of 13.3° and cut a perfect compound miter joint.

What you will find in other books are instructions that say "for those corners that are not 90° just adjust your saw until you get the corners to fit". Here is where everyone loses it. You have created a huge pile of firewood from your expensive crown molding and now have an ulcer and give up.

Let's start by explaining just the basic compound miter cuts to install crown molding for a horizontal ceiling.

Standard Corner Turns

This is the most common type of crown moulding cut. The crown runs along the wall and ceiling and will make a horizontal turn of some angle in a corner and continue on along the ceiling. The ceiling is horizontal but the corners are almost never exactly 90°.

Standard Corner Turns consist of two types, Inside Corners & Outside Corners. (These are cut somewhat different, as we will demonstrate.)

Inside Corners - Corners that measure between 0° to 180°.
Outside Corners - Corners that measure between 180° to 360°.

Crown Molding Inside Corner Turns

Left-hand Side Piece of Crown Moulding


Right-hand Side Piece of Crown Moulding