How To Properly Cut Crown Mouldings

Curious about crown moulding cuts? 

Ready to give your walls a serious upgrade?

When cutting crown moulding, there are four types of cuts you need to know for different situations. Read below on how to properly cut crown mouldings during your next project.  

Overall Good Things To Know About Cutting Crown Mouldings

Outside Corner

1. Left Side: Ensure the mitre saw is left at 45 degrees. Save the right end of the cut.
   1. For the left side of an outside corner, swing the blade to the left and keep the right end of the cut.
2. Right Side: Ensure the mitre saw is right at 45 degrees. Save the left end of the cut.
   1. For the right side of an outside mitre saw, swing the blade to the right and keep the left.

Inside Corner

1. Left Side: Ensure the mitre is right at 45 degrees. Save the right end of the cut.
   1. For an inside corner on the left side of a wall, pivot the mitre saw blade 45 degrees to the right and save the right end of the cut.
2. Right Side: Ensure mitre is left at 45 degrees. Save the left end of the cut.
   1. For an inside corner on the right side, pivot the blade 45 degrees to the left and save the left end of the cut.

Be sure to place it in the mitre box at the same angle that it will be placed on the wall. Ensure that the painted side is facing up and with the ceiling edge at the bottom of the mitre box.

A power mitre saw is the best way to cut crown moulding once you measure the angles. The saw can be adjusted to cut at any angle – set it to 45 degrees for one side of a standard 90-degree corner. The saw can be set to 45 degrees to the left or 45 degrees to the right.

How To Square Cut Crown Moulding

Square cuts are the simplest and are used to create an end joint, where the cut end of the moulding fits flush in a corner. 

Follow the steps below to cut the types of moulding that rest against a wall. 

1. Start by measuring the distance from the corner on the first wall. 
2. With the mitre saw set to 0 degrees, make a straight cut to create the end joint where the end of the moulding will be flush against the wall in the corner.
3. This simple cut is to be used in between crown moulding corner blocks, as described below.

​​How To Use Scarf Joints For Crown Moulding 

Scarf joints are used to connect two pieces of crown moulding when the wall is longer than a single piece of the trim. Two pieces are cut at opposing 45-degree angles and overlap to create a splice. 

1. Change the mitre saw so that it is 45 degrees to the left.
2. Before cutting the first piece, ensure that it is upside down with the scrap end to the right.
3. Brace the flat top of the moulding on the base of the saw and the flat bottom of the moulding against the saw’s fence.
4.  Cut near the end of the moulding.
5. To complete the splice, turn the blade 45 degrees to the right and place the second section of moulding upside down on the saw with the scrap to the left.

How To Cut Outside Corners of Mouldings

Crown moulding outside corners, or outside mitres, are cuts used when a room includes more than just four corners. Bay windows, a chimney or an entryway can prevent your crown moulding from creating a simple square or rectangle along the ceiling.

To properly cut the outside corners follow these steps:

1. Measure from the outside edge of the corner, back along the wall to the end. Tag the measurement on a piece of trim moulding with a pencil.
2. Place trim moulding on a mitre saw in the position it will go when added to the ceiling. 
   1. Put the first end of the moulding under the blade.
3. Turn the blade to 45 degrees outward. Make sure it’s pointing away from the section of the trim you measured. 
   1. Cut the trim.
4. Measure from the same outside corner, on the joining wall.
   1. Repeat the process, marking and cutting the trim with an outward 45-degree angle.
5. Hold the two pieces of trim in place on the wall – the outside mitre cuts should end against each other at the outside corner. 
6. Secure the trim in place with finishing nails every foot or so along the top and bottom edges of both pieces.

How To Cut Inside Corners (with a Coped Joint)

Wall corners are rarely a perfect 90 degrees and gaps in the wood joints can be unsightly and don’t create a finished look.

The easier method of cutting crown moulding to get a tight seam for an inside corner is with a coped joint. 

This technique of how to cut crown moulding inside corners requires an inexpensive hand saw called a coping saw to remove the extra material.

The blade is thin and can easily follow curves and some angles as you undercut the moulding’s profile. Take your time. You can pare away more if you find that you need to.

How To Install Crown Moulding Corner Blocks

These pre-cut decorative blocks can be used where the ceiling meets a wall corner.

To install:

1. Nail two blocks in opposite corners of a wall, then measure the distance between them. 
2. Measure and cut crown moulding with a straight cut to fit in between the blocks.

Conclusion

Have questions regarding how to properly cut mouldings or would like to speak to one of our contractors?

Feel free to visit our flagship store and see how we can help you finish your project. We are also available to chat to address your questions as you are cutting the mouldings.