How to Install Decorative Columns
They may look load-bearing, but decorative columns are actually an easy way to add class and style to your home.
If you want to add a distinctive and timeless touch of class to your home, consider adding columns. After making the initial commitment, there are many more decisions to come. First, you need to select appropriate locations — where the columns actually appear to be performing a supporting role, even if they are purely decorative. Second, choose the material of the column. You'll find stain- and paint-grade hollow-wood columns as well as synthetic materials, such as the fiberglass version shown here. Third, select a style that's appropriate for your home. Although it's tempting to select the most ornate version, a bit of restraint goes a long way.
When you order your columns, you'll probably have to purchase a stock size slightly longer than the finished size. Also check on the availability of factory-split columns, such as a quarter column, half (shown in this installation), or three-quarter. The manufacturer also may be able to supply other designs that would suit your needs.
Shopping for Columns
When you shop for columns, you may discover that the shaft does not have a consistent diameter along its entire length. For example, the columns in this installation were made with a straight section along the bottom one-third of the length and a taper along the upper portion. This is why columns are sold in a variety of lengths and why you must trim them from the bottom only, never removing more than one-third of the total length.
You may also discover columns that have slightly bulging sides. The ancient Greeks discovered that perfectly straight columns didn't look right — the sides seemed to curve inward. That's why Greek architects introduced the concept of entasis, which is a slight convex curve along the column's shaft. This swelling overcomes the illusion of concavity and makes the eye see the column as straight.
Installing Full-Round Columns
If columns support a structural load, you'll need to cut them to exact length, and in remodeling, that usually means that you have to jack up the structure, insert the columns, then lower the structure onto the top of the columns. A square cut at both the top and bottom of the column is important in order to have an even distribution of the load through the shaft's section.
Your local building codes may prescribe that exterior structural columns also be able to resist uplift — the roof-raising force that can occur during hurricanes or tornadoes. If you plan to cut into a structural column or attach another load to it, you'll need to consult the column's manufacturer and possibly seek the services of a structural engineer as well.
With either decorative or structural full-round columns, you need to remember to slip the plinth and capital collars onto the shaft before sliding the shaft into position.
Step 1: Measure Area
Measure the height of the installation site so you can place the order for the columns. Also ensure that the site is large enough to accommodate the width and depth of the capital and the plinth.
Step 2: Cut Column
Subtract 1/4 inch from the measured height, then mark a cut line near the base of the column. Triple-check the measurement, then cut the column to length with a handsaw. The edges of a fiberglass column, like the example shown, can be sharp, so dull them with a few passes of a rasp.
Step 3: Measure Base
Mark the side-to-side centerline on the surface where you'll set the base of the column. Make certain that the platform is sturdy enough to support the column's weight. Just as important, this base surface must have a substantial appearance because those viewing it will assume that this column plays a role in supporting your house.
Step 4: Mark Vertical Centerline
Transfer the horizontal centerline into a vertical centerline for the column. Extend this line all the way to the top of the installation. Extend the centerline onto the ceiling, then mark about 2 inches toward the center of the room.
Step 5: Make and Install Backerboard
Measure the inside diameter at the top of the column, then rip a piece of 3/4-inch-thick lumber into a backerboard that will fit inside the column for the top one-third of its height. If the column tapers, ignore it and simply get a decent fit at the top. Mark the centerline at the top end of the board, check its edge for plumb, and fasten it to the wall with nails or screws.
Step 6: Drill Pilot Holes
Drill countersunk screw shank clearance holes through the edges of the column for screws that you'll drive into the backerboard. The capital will cover the topmost screws. Space additional screws no farther than 12 inches apart until you reach the bottom of the backerboard.
Step 7: Screw Clearance Holes
Mark a centerline at the top and bottom of the column's face. Drill angled countersunk screw shank clearance holes at the centerline near the column's top and bottom ends.
Step 8: Place Column
If you're working with a tall column, recruit a helper for the next steps. Hoist the column into position, then drive tapered shims under the end on each side until the top of the column touches the ceiling. Make certain that the column's centerline matches the horizontal one on the support surface.
Step 9: Drive Screws
Drive a screw to secure the bottom of the column. Stop the screw as soon as it touches the column so you don't strip the hole or misalign the column. Drive a screw at the top centerline of the column and along both edges into the backerboard.
Step 10: Attach Base
Drill countersunk screw shank holes through the plinth (base), then drive screws to secure it to the mounting surface. Again, stop driving as soon as the screw makes solid contact with the material.
Step 11: Attach Top
Drill countersunk screw shank holes through the capital (top), then drive screws to secure it to the ceiling.
Step 12: Caulk and Finish
Apply caulk along all the seams. Then you're ready to apply the finish.
Faux finishes — paint finishes that mimic materials such as marble — were once the exclusive domain of talented artisans. But the popularity of these surface treatments has inspired paint manufacturers to craft carefully blended colors and specialized tools to make these decorative looks more accessible to do-it-yourselfers.
Although convenience packaging doesn't completely remove the need for painting skill, you can inexpensively try your hand at creating a marble or granite finish. Craft stores and paint dealers usually sell materials along with decorative-painting books with step-by-step instructions.
Granite is one of the easier stones to fake. It generally has a regular appearance throughout the entire piece. Instead of relying on your memory or imagination when it comes to the stone's appearance, purchase a piece of granite tile for reference. A tile dealer will likely have several samples from which you can choose. As you study the sample, notice that the stone has a dominant tone but also a wide range of tones in other colors.
Marble requires more artistic skill to convincingly mimic. Again, purchase a tile or two for reference, and aim for boldness instead of fussy detail.
If you ultimately discover that you're not a faux finisher, you can hide the evidence under a coat of primer and paint. After all, the purest marble is snowy white.