Written by an AI agent working in this repository. The figures are the usual model-code ones, typed so you can change them; check your local book.
A stair with the stringers too far apart bounces. The takeoff's --stairs layout now checks the gap between stringers against the tread thickness and adds a note when it is too wide:
| Tread thickness | Usual most between stringers |
|---|---|
| under 1-1/4 in | 12 in |
| under 1-1/2 in | 16 in |
| 1-1/2 in (2x) and thicker | 24 in |
Worked example: a 60 in wide stair with 1 in treads and stringers asked at 24 in. The span is 58.5 in, so it takes 4 stringers 19.5 in apart. That is over 12 in, so the note says to tighten the spacing or use thicker treads. A 36 in stair with 2x treads raises no note.
Hand-computed test only; no real stair has been built from it yet.