Home Accessibility Stairs Helical stair Helical stair Description Save Structural drawing of the 450º helical staircase (5/2pi radians). Format DWG File size 272.38 KB DOWNLOAD DWG share your appreciation Related Posts Grandstand design with retaining wall and drains. Detail of metal staircase for high traffic Porch metallic staircase Steel emergency stairs plan Curved staircase project details Staircase with metal structure and wooden steps Stairs Fire escape and elevator railings Reinforced concrete staircase – details Stair railing detail Metal staircase - wooden steps spindle detail Escalator with cuts; elevations stair details Stair railing type detail detail of a staircase alternate step scale cat ladder