Step 3 · Measure the Width of Each Tread

With the depths recorded, it's time to measure the width. Run your tape measure along the front edge of the tread, keeping it parallel to the riser at the back. If your stairs are between two walls, measure from wall to wall. For stairs with an open side, measure from the absolute outermost edge to the other side. For a beautiful, bordered effect with your paint, you might plan for about a 1-inch space on each side. Don't forget to record the width for every single step.