Cutting Mitered Joints for Trim Molding

Trim molding is an essential part of interior design, since it can hide rough edges and corners of walls and floors. In order for these to be formed and connected together at the corners, they have to be mitered at 45-degree angles for them to match smoothly and cleanly. This gives off a better interior design and makes your molding attachment look neat.


  • Miter Saw
  • Trim Molding
  • Pencil
  • Fine Sandpaper

Step 1: Measuring the Molding Length

Place the molding against the wall into the corner, in a position where you want it to be installed later. On the end that is by the corner of the wall, mark the top portion of the molding about 1/2 inch from the corner. This will be the point of the first 45-degree miter cut.

Step 2: Cutting the Molding

Set the miter saw to cut at a 45-degree angle. Place the trim on the mark in such a way that it is positioned the same as it will be when placed on the wall. Position the blade a couple of inches above the molding, turn it on and start to cut by pushing it down gently, but firmly.

Step 3: Measuring and Cutting the other Molding

Do the same steps with the next trim that is to be attached to the first set of molding that you just cut. It is the same process, but the cut angle will be in the opposite direction.

Step 4: Aligning the Molding

Align the boards together and test fit them into the corner to see if they are a perfect fit. If there are some gaps, use sandpaper to smooth out the edges, until the trim molding fit perfectly together.