A flat seat plate under the rear end of a stair tread with a wedge gusset beneath it, resting on a stringer or spine.
Category: Stairs › Staircases › Stair Flights
By Huu Khanh Nguyen · Updated November 14, 2026
| Name | Default | Unit |
|---|---|---|
| Riser height | 175 | mm |
| Going, nosing to nosing (y) | 250 | mm |
| Nosing overhang of the tread beyond the riser line (y), 0 = a triangular gusset | 25 | mm |
| Length of the seat along the run (y), from the plate front to its rear edge | 88.9 | mm |
| Seat plate width across the flight (x) | 370.078 | mm |
| Gusset width across the flight (x) | 152.4 | mm |