| Top Landings for Spiral Stairs
Spiral stairs usually cannot be placed under a floor edge due to headroom restrictions as you pass under the edge when you go down the stair.
As an example, imagine looking down from above on a spiral that is sitting next to the edge of a top floor. Its outline would be a circle next to a line that represented the top floor (Figure 1).
* National building codes allow spiral tread rises up to 9-1/2" to maximize headroom clearance.
Figure 3 shows the spiral set out from the floor edge with the top landing installed. The landing acts as a bridge from the floor to the top spiral tread. The landing allows you to go down further before you pass under its edge, increasing your headroom.
Another important function of the landing is that it anchors the top of the spiral to the top floor system. The landing deck (walking surface) acts to stiffen the spiral top against sideways movement.
Each Precision Pine interior spiral kit includes the top landing as well as horizontal handrails required to guard the open sides of the landing.
© Precision Pine 2006
Precision Pine, Inc.,
7322 Hodges Ferry Road,