How to Measure the Length of Crown Molding

By Michael Logan

Crown molding installs on top of cabinets and also transitions the joint between walls and ceilings with an interesting architectural feature. Products are available in various profiles and widths from 2 inches to 6 inches or more, but profiles and widths won't affect measurements. Accurate measuring for any molding installation is essential -- cut a piece too short and it is only suitable for short runs or scrap. Making crown molding measurements is similar to measuring other moldings, but a few techniques can simplify measuring and cutting.

List of Items Needed

  • Tape measure
  • 4-foot level
  • Miter saw

    Cabinet Top

  1. Hook the tape measure on one side of the cabinet at the top and pull it out along the front face of the cabinet to the other side. Read the measurement on the tape measure at the point where the cabinet face ends.

  2. Measure along the cabinet side from the back of the cabinet to the front along the top edge. Make a third measurement on the opposite side. Most cabinets are very square, but even small differences will show up in the final result.

  3. Add 1/16 inch to the measurements. You can shave small amounts off the length of the crown to make adjustments as necessary. A tight fit is preferable to a loose fit.

    Walls and Ceilings

  1. Measure along the wall close to the ceiling beginning at an inside corner. Make a mark at 10 inches.

  2. Measure from the opposite corner to the mark made in the previous step. Add 10 inches to the measurement, then add 1/16 of an inch to the total length. Measuring to the mark eliminates errors made by bending the tape measure in the corner.

  3. Place the level horizontal on the wall and against the ceiling at an outside corner. Draw a light pencil line along the level to extend the line of the wall on the ceiling. Measure from the inside corner to the line for an accurate measurement. Repeat for the other side of the outside corner.

    Measuring Marking and Cutting

  1. Plan the crown molding installation to work around the room in a clockwise direction, measuring, cutting and installing each piece in order. This helps prevent errors and eliminates complicated measurements and planning for pieces with two coped ends.

  2. Cut the molding at one end before measuring and marking the molding to the next cut. Complete cope cuts on the molding before measuring and marking for the cut on the opposite end.

  3. Hook the tape measure on the cut end of the crown molding on the bottom edge and pull it out along the molding. If the end of the molding was cut on an angle for an outside corner, have a helper hold the end of the tape measure in place.

  4. Transfer measurements to the molding and mark them on the wall edge. Place the crown on the miter saw with the wall edge against the fence and the ceiling edge against the table. Align the side of the blade on the waste side of the cut mark to make the cut.

Tips and Warnings

  • Cutting the molding slightly longer than necessary serves two purposes. It makes for tighter-fitting joints that won't open up and you can always cut more off if you need to, but you can't add more on if the piece turns out too short.
  • On long runs over 8 feet, a piece cut slightly longer than necessary might bow out a little from the wall. Align the ends, nail them in place and then nail the center in. The end joints will tighten and never open up.
  • Handheld rotary tools with cutting wheels and sanding drum bits make coping miters easier.
  • Wear safety glasses while cutting and installing crown molding.

© Demand Media 2011