Center Balusters Per Tread
By far, this is the questions that is most often asked. “What is a center baluster?” Balusters are the steel spindles/pickets that are on your stair. Simply put, balusters are the bars that go straight up and down on your spiral stair.
With an emphasis on “center”, Center Balusters are extra steel spindles/pickets. Your center balusters are what you see in the middle of the treads and they connect the tread to your handrail.
When we say “center balusters” the emphasis is on center as the basic build provides a baluster connected to the front of the tread as well as the back of the tread.
By adding center balusters, you can decrease the gap between your balusters for additional measure of safety.
Code compliant stairs would be a 5’ diameter stair with 2 center balusters. This will establish the balusters with a 4” on center spacing so that a 4” sphere cannot pass through the balusters.