It is not difficult to install wainscoting on a staircase. Wainscoting is wood paneling with small vertical strips that are about 1½ inches wide. Wainscoting can be found under chair rails or on staircases. Follow the simple steps below to effectively install wainscoting on your staircase.
Measure the Angle of the Stairs
Use an angler to measure the angle of the stairs. Place one arm of the angle finder against the vertical rise of the stinger and the other arm on the stinger’s diagonal side going up. This is the angle need to cut the tops and bottoms of the stiles and the panel tops and bottoms.
Measuring and Cutting the Lower Rail
The lower rail is usually 8inches high, but a full height lower rail does not need to be installed diagonally up the stairs. Not only will it be too big, but it will protrude into the panel too much. That will make the stair panels look too small. The lower rail has to be cut down (maybe at least 4 to 5 inches in height; whichever one works best).
The lower rail and the vertical face of the stinger should butt up flush. From the stringer on the lower rail, measure back 4 inches horizontally and make a 45-degree cut. The cut should end halfway down on the lower rail.
Positioning Transition Stiles
Place the bottom transition next to the stile and the top transition above the stile. This accommodates the stringer without interfering with the panel or protruding into the panel. With this method, you do not need the L-shaped panels since they are harder to cut and harder to shape using a router. The small transition is on the top rail between your horizontal installation and the diagonal one.
The same rules will apply for the lower transition. The only difference is the top rail which is installed at the full height (this should not be cut down). The variable angle will be the same for the top and bottom of the install.
Fill in any seams, nail holes, and corners on the wainscoting using a spackling compound. After the spackling has dried, you can sand it down with fine-grit sandpaper. You can use caulk to fill any seams between the wall and the wainscoting. This also will give the wainscoting the ability to move while the wall and the home expands or contracts in various weather conditions.
Once you are done sanding and applying caulk, you can apply a finish coat of paint. Semi-gloss paint may be best as it is easiest to clean.