Plan multiple stories as one coordinated building

Planning workflow

1. Set floor-to-floor elevations and a consistent reference origin.
2. Reserve the complete stair volume, including landings and headroom context.
3. Align likely supports and wet rooms where practical.
4. Review upper-level openings, roof geometry, and vertical routes in section as well as plan.

Formula or decision logic

Total building height equals the sum of floor-to-floor heights plus roof geometry above the top level. Stair planning begins with rise count = total rise / target riser height, rounded to a whole number; actual riser height = total rise / chosen rise count. That arithmetic is a planning check only and must be validated against locally adopted requirements.

Worked planning example

With a 9 ft floor-to-floor rise and an initial 7.25 in target riser, 108 / 7.25 = 14.9, suggesting 15 risers. The resulting riser is 7.2 in. The plan must still reserve the full run, landings, width, guards, and headroom, and a local professional must confirm the adopted code and structure.

Limitations and review boundary

• Plan overlays do not calculate loads or member sizes.
• Stair requirements vary by use and adopted code.
• Mechanical and plumbing routes need trade coordination, not just aligned symbols.

Continue in design planning