How do I Install Crown Molding?

Crown molding adds character, style, and a finished appearance to any room. The most common placement is at the seam where wall meets ceiling, and options in design range from the extraordinarily ornate to draw the eye and deliver an aesthetic punch, to a simple cut and line that completes a room, but does so in a clean, subtle, simple manner. There are several things to consider before beginning to install crown molding. First, the visual goal should be determined. This is a factor in selecting the appropriate materials to install crown molding for your specific project. There are several general types of crown molding to select from.

Plaster

This is the material to work with for the grandest, high style projects. Elaborate designs are made by pouring plaster into a mold, and this material does not shrink or warp. On the down side, plaster is heavy, it can crack, and the cost is prohibitive because most plaster molding is a custom purchase. This is not the product for the novice who wants to install crown molding as a DIY project.

Solid Wood

To install crown molding made of solid wood is another visually appealing choice. It can be stained and is offered in both ornate and simple designs. The drawbacks are shrinking and swelling with the weather, and it’s difficult to cut.

Medium Density Fiber Board (MDF)

MDF is friend to the DIY installer who wants the look of real wood. It’s lightweight, comes in many design options, and it is a low cost alternative to solid wood. Though still difficult to cut and most suitable for trim that will be painted, there is an option to purchase MDF with a veneer that allows staining.

Polyurethane

Anyone who wishes to install crown molding can work with Polyurethane. It’s light, inexpensive, repels insects, and comes in elaborate designs similar to plaster. Unfortunately, it is only suitable for paint, not stain, and it dents easily.

Once style and materials are selected, the next step is to measure. Add 10 percent to the linear footage to allow for mistakes. Apply any paint or stain to be added, then decide which way is up. Look for a “wave” on one side of the molding. This is called the cyma recta, from the Greek words for "wave" and "upright.” This is the side that should abut the ceiling.

Now it’s time to cut. The easiest way to cut crown molding is to use a miter saw. The back of the molding has two flat spots where the molding will rest against the ceiling and the wall. Put the molding in the miter box with the flat that will touch the ceiling on the bottom and the other flat against the side wall. This mimics the molding’s position on the wall and ceiling.

Now, cut 45 degrees for 90 degree corners or adjust it to fit as needed. Locate the ceiling joists and wall studs, then screw a 2 inch x 2 inch (5 cm x 5 cm) length of wood to the joists, creating an area to nail the crown molding. Finally, use 6D and 8D finishing nails to secure the molding. It is relatively easy to install crown molding, and the visual impact gives a lot of bang for the buck.