Duplex Flight

By Huu Khanh Nguyen · Updated October 29, 2026 · stair, stadler, duplex, sawtooth, flat-string

A straight stair flight with a sawtooth steel string on the wall side and a flat steel string closing the room side.

Parameters

Name	Default	Unit
Number of risers (the flight has risers - 1 treads)	14
Riser height	190	mm
Going, nosing to nosing	230	mm
Overall width across the strings	1000	mm
Nosing overhang of the treads beyond the riser line (y)	25	mm
Tread thickness (z)	40	mm
Riser boards	true
Riser board thickness	19	mm
String thickness across the width (x)	44	mm
Throat: string material under the inside corner of each cut, across the pitch	127	mm
Flat string thickness	10	mm
Flat string depth	230	mm
Finish of strings and risers	white
Width	width	mm
Height	risers * rise	mm