Panelboard Installation on Stairs

Measuring

• Obtaining correct measurements is essential for successful installation of panelboard in a stairwell. Measuring the length of the stairwell, as well as the distance between the ceiling and each stair tread, helps you determine how many panels you need to complete this project. You also need to measure the rise and run of each individual step--that is, the depth of each stair tread and the distance between the top of each tread and the next step. Avoid assuming that all steps have the same measurements, particularly if you are installing panelboard in an older home. If the ceiling above the stairs slopes, draw a horizontal line 6 inches out from the ceiling, then place the bottom of a protractor along the ceiling to determine the angle of the slope. Also, measure the locations of the bolts that hold the rail to the wall, as well as the diameter of the bolt shafts.

Locating Studs

• Before cutting panelboard for the stairwell, you need to determine the location of the studs behind the walls on both sides of the stairwell. The panels should be nailed to the studs to prevent them from coming loose. An electronic stud finder can help you quickly and easily locate the studs. Turn the stud finder on, and make a mark near the ceiling and the stairs at each location where the stud finder beeps. Snap a chalk line between each set of marks.

Marking and Cutting

• Lay out enough sections of 4-by-8-foot panelboard, with the long ends adjacent, to cover the length of the stairwell. Mark the slope of the ceiling on the panelboards, and use the measurements you obtained earlier to draw an outline of the stair profile. Mark the stud locations with a chalk line. Cut out the ceiling slope and the stair profile with a jigsaw. Number the back of each panel so you can keep them in order during installation. Repeat this process for the panels that will cover the other stairwell wall. Mark the locations of the bolt holes on the set of panels that will cover the wall supporting the handrail.

Installation

• Remove the handrail by loosening the bolts with a ratchet. Remove any molding with a pry bar. Install the first panel by driving 3-inch nails through the stud lines at 4-inch intervals. Continue this process until you have covered both sides of the stairwell. Attach the handrail by tightening the bolts through the panelboard with a ratchet. Replace the molding with 3-inch nails.