Molding Guide

Installation Instructions

Above all Measure Twice and Cut Once

Doing moulding instllation is as easy as  1, 2, and 3.

  1. Starting With The Right Tools.
  2. Since one only needs a few tools to install your wood moulding, one should invest in quality tools. This will make your project easier and the finished product will look more professional.  Following is a description of the required tools as a minimum:

    Miter Box Back Saw Coping Saw
    Hammer Finishing Nails Nail Set
    Wood Putty Tape Measure Sandpaper

    There are many other tools that may accomplish the task.

    It may be easier to paint the moulding prior to installation. After installation one may simply touch up the required areas.

  3. Knowing How Much Moulding One May Need
  4. When you have decided on a project, you will need to measure the length of each wall, component or item that requires moulding to purchase the correct amount. Add one (1) foot to each measurement for potential errors and cuts.

    By using a graph sketch the required moulding areas. Record the areas in systematic way.

    Item Length Add Total
    Area 1 5 1 6
    Area 2 6 1 7
    Area 3 15 1 16
    Area 4 12 1 13
        Total 42 Feet


    Outside Corners, Door and Window Casing – When measuring for moulding around these areas that may require mitering on the ends, add the width of the moulding to each piece for each miter.
    Example, the top casing for the door requires twice the width because each end is mitered. If the door casing requirement is 36 1/2 inches and the casing width is 3”, then you would need 42 ½” (36 ½ + 3 + 3) plus the foot. That would be 43 ½” or round up to 44”


  5. Knowing the Right Cutting and Installation Methods

Mitering – Mitering is the basic operation in which an angle is cut across the moulding using a miter box and back saw. A back saw is used because it has a very narrow kerf and the back of the saw has been stiffened for stability during the cut. Inside and outside corners, and moulding around windows and doors are usually cut at a 45-degree angle. Make sure you know what side of the line to place the cut. The saw kerf on the incorrect side will result in an improper fit.

Coping – This technique is used when butting one moulding against the profile of another.
First, set the moulding in the miter box as it is to be installed on the wall – upright against the back plate of the miter box. Cut the end of the moulding at the 45-degree angle. The cut then exposes the profile on the end.
Second, with the coping saw, follow the profile and cut at a 90-degree angle to the face of the moulding. This results in a duplication of the profile that will fit over the face of the adjoining moulding in the corner. This method is only valid if the moulding is to be installed flat against the wall or component.

45-degree cut

    45 degree cut


Crown moulding that is installed at an angle away from the top of cabinets or between the wall and ceiling require a compound cut at the corners. This technique is much more difficult and requires practice and no doubt errors.  Practice on some scrap wood first to understand the requirements.  Using MDF crown moulding as practice is a low cost method for refining your skills.  Real wood crown moulding is very expensive.

Splicing – In order to install moulding over large spans, you may have to splice two lengths of moulding together.  The moulding is spliced with a vertical 45-degree or an angle 45-degree seam. If the seam is a vertical 45-degree seam – place the two pieces of moulding in the miter box together and cut both angles at one time. Do not cut at a 90-degree angle, this is a butt joint and is one of the weakest joints.

If you are to use the angle 45-degree method, then your miter box needs a cutting slot that extends from the top to the bottom, either to the left or right, at a 45-degree angle. Again place both pieces in up against the back plate and then cut.

Gluing the joint together will strengthen the joint.

Installation – If you are installing a hardwood moulding, you may have to drill the nail hole first. The wood may split due to the nail or the nail will bend when attempting to drive it in the wood. Prior to nailing place a piece of masking tape over the spot that you plan on placing the nail. This tip will all you to then set the nail, apply putty to fill the hole and then paint the putty spot. When the paint is dry remove the tape and it is a go.