By Huu Khanh Nguyen · Updated October 29, 2026 · stair, curved-flight
A flight of stairs that turns on an arc, built of solid precast blocks cut to the radius, each step one block laid on a prepared bed with no stringer.
| Name | Default | Unit |
|---|---|---|
| Number of risers in the flight (the flight has risers - 1 blocks, the upper level is the landing) | 21 | |
| Riser height | 150 | mm |
| Radius of the inner edge of the flight in plan (the well) | 1000 | mm |
| Radial width of the flight, the block length | 1000 | mm |
| Total turn of the flight in plan | 180 | ° |
| Direction of climb seen from above | left | |
| Underlap, the rear part of a block that lies under the next block, measured on the middle radius | 70 | mm |
| Bed joint between a block and the block below it (z): block height = rise - joint | 10 | mm |
| Finish | white | |
| Plan angle of one step | angle / (risers - 1) | ° |