Roller/benders in the steel industry (those who specialize in curving steel) often work with miscellaneous and ornamental fabricators providing them with helical stair stringers to create circular stairs. Most often these circular staircases are rather large, suitable for a ballroom or spacious, multi-story atrium. Indeed they are called “monumental stairs.”
The most common circular stairs, however, are much smaller and compact, easier to fabricate and assemble and less expensive. This kind of helical stair is commonly referred to as a “spiral staircase” due to the stair’s design: the geometry of the staircase is much more spiral in nature than other types due to the stair’s steeper pitch and a much tighter design radius. In most all instances spiral staircases are left exposed, meaning that their structural components are not hidden within a wall or buried behind sheetrock or wallboard, leaving the stair’s structural elegance visible for all to see.
Spiral staircases will usually be seen in residential applications, spanning from a basement to a main floor or from a main floor to a loft. In outdoor applications they are commonly seen in elevated decks extending from the side of a house. They are usually much more compact in size, with their outside stringer around a 5’-0” radius more or less, making them perfect for areas with limited space.
Due to the simplicity of their design, all that is needed are a few dimensions. Spiral staircases can usually be purchased in kit form from your local staircase fabricator who, in turn, might contact a roller/bender for special applications.
Many spiral staircases are all very similar in design and are primarily centered and assembled around a central pipe rising from floor to floor, acting as the inside stringer. The stair’s treads are attached directly to the center pipe in such a fashion that allows the treads to shape the staircase in a helical/spiral fashion. The helically curved parts that make up a spiral staircase are the outside stringer and the stair’s individual railing components. Spiral Staircases are very elegant and have the ability to modernize your space; transforming a limited area into the focal point of a room.