Choosing the Material

Begin by deciding on the material that you will be using. You need to choose between a standard 4″ or larger crown moulding, between composite (often MDF) or solid wood, and you will need to determine the width of baseboards that you will use. Different types of moulding and baseboard will require different ways of cutting the material.

If you use 4″ crown moulding you can use a standard 10″ mitre saw. You’ll be able to stand the moulding on edge and cut the mitres without the need for a compound mitre saw. If you use a larger moulding you will need a sliding compound mitre saw, requiring you to use specific angles to cut and fit the material properly. Composite moulding is a bit easier to use, as you can use caulking and paint to hide gaps and other imperfections. With solid wood you have to be a bit more careful when cutting and installing.

Inside and Outside Corners

You will have both inside and outside corners on the walls of your rooms to contend with. Cutting the mitres for solid or composite moulding and baseboard on the outside corners is straightforward. However, for solid wood stock, you should cope the moulding on the inside corners. The reason for this is that not very many corners are a true 90º, making it difficult to ensure a perfect joint. Additionally, there is some likelihood that solid wood moulding will shrink in size over time. With composite moulding, you will be able to fill any imperfections, but with solid wood, you need a nice tight joint for that professional look.

Measuring and Cutting

As with any woodworking endeavour, you want to be accurate in all your cuts.
You have to measure from corner to corner of the room and around any sections of the wall that jut out (what are called ‘jogs’). After you get all the measurements, add them together and add 15% for waste. This will give you the amount of material you will need to purchase without having much of it left over. As an example, if you measure a total of 55′, add 15%, so you would need a total of 63′. When you cut the material, make sure you have a sharp blade on the saw. That will cut down on chip-outs which can ruin the looks of the finished product.

The Baseboards

For composite material, cut each miter for outside and inside corners at half of the degree of the corner. For example, if the corner is 90º your mitres will each be 45º. Before cutting your material be sure to check the angle for each corner.

For solid material, cut the outside corner as you would for composite material. For inside corners, square cut the first piece and butt it into the inside corner. Then cope the second piece to fit into the inside corner. Coping involves cutting the end of one piece to the same profile as the face of the other. An easy way to get the profile is to make a 45º cut on the end of the piece you will be coping, then use the cut as a guide. If you need to cope just a few inside corners, it’s easiest to do so by hand with a coping saw. However, if you have a lot of joints to cope, then you will want to consider a jig that simplifies the cutting of multiple coping joints, like the Coper (Canadian Woodworking, June/July ’04, Issue #30).

When you have to join shorter pieces use a ‘scarf joint’. To accomplish this you will make a 30º cut on each piece (opposite to each other) and lap them so they look like one piece. Glue the pieces together during installation.

Crown Moulding

Cutting mitres for the crown moulding takes careful measuring and patience. For 4″ moulding, stand the piece on edge to cut the compounded angle. The most important thing is to hold the moulding with the bevel against the fence of the saw. For cutting moulding wider than 4″ you will have to use a compound mitre saw. Refer to the accompanying graph to determine which bevel and mitre you need to use when cutting the moulding. You need to have the proper side of the moulding against the fence and know on which side of the blade the finished cut will be made.

For inside corners

Left side – Place the ceiling side of the moulding against the fence. The finished cut will be on the left side of the blade.

Right side – Place the wall side of the moulding against the fence. The finished cut will be on the left side of the blade.

For outside corners

Left side – Place the wall side of the moulding against the fence. The finished cut will be on the right side of the blade.

Right side – Place the ceiling side of the moulding against the fence. The finished cut will be on the right side of the blade.

When cutting composite material use the angles in the accompanying table. If you are using solid wood you should cope the material on the inside corner. To do this, square cut the end of one piece and butt it into the corner, then compound mitre the other piece and cope it (as you do with the baseboard) to fit into your corner.

Installation

When you attach your moulding and baseboard to the wall I suggest using an air compressor and nailer. This makes the final step easier, cleaner and faster. You can hand nail the material, but you should be extra careful not to miss with the hammer, in which case you will dent or damage the wood. When nailing the baseboard and crown moulding, you should try to nail it to the studs in the wall.

This will hold the material more securely. All corners and joints should be glued so they won’t come apart over time.

For composite moulding and baseboard you will need to fill the nail holes and corners with paintable filler. After the filler dries, sand it flush, and then paint it. Apply a paintable caulking where the material meets the wall so you won’t see the joint line.

For solid wood material use a matching coloured filler to fill the nail holes and any imperfections in the corners. Make sure you wipe the excess filler off before it dries. Where the material meets the wall, a paintable caulking can be used so you don’t see the joint line.