It’s okay for the balusters to be spaced closer than 4 inches but not further apart. When determining baluster placement, don’t forget to consid- er the shape of your newel posts. For example, the trim around the bottoms of our newel posts made them 1-1/2-in. wider than the tops of the posts—so we took measure- ments between the tops. If you for- get this discrepancy, then a balus-
ter spaced 4 inches away from the bottom of the newel might be spaced 4-3/4-in. away from the top of a newel, which would be a code violation. On the post-to-post staircase shown, the total run of the balustrade is the horizontal dis- tance between the two opposing newel faces. We used the calcula- tions above to determine the prop- er center-to-center baluster spac- ing for the total run, then marked these locations on the stair treads. We then turned our attention to the handrail, with plans to return to the balusters later.
RAIL INSTALLATION To determine the miter angles of the handrail, we placed a scrap 1x2 board atop the stair treads and clamped it alongside the newel posts, marking the inter- secting angle with a pencil. The board was cut along the miters to serve as a template for the rail. We placed the 1x2 flush between the newels at the rail-connection points to double-check the fit of
Determine the center-to-center baluster spacing and mark their positions on the stair treads. Illustration © L.J. Smith Stairs Inc.