Straight-run stairs. Single flight, simplest geometry, fastest install.
When the floor-to-floor height fits a single flight and there's room at the bottom for the run, a straight-run stair is the fastest answer — fewest pieces, simplest installation, lowest cost. Most of our mezzanine-access work and grade-level equipment exits use this configuration.
Where it fits
The default when geometry allows.
A straight-run is the right choice when (a) you have the linear floor space at the base for the run, (b) the rise is under ~16 risers — about 9 ft floor-to-floor — so a code-required intermediate landing isn't triggered, and (c) the egress path is satisfied by a single flight. Below those constraints, look at switchback; above them, you may need an exterior fire-escape stair.
Common applications
- Mezzanine access — single flight from grade to a single-tier platform. See mezzanine access stairs.
- Equipment platforms — service access to a low-traffic platform.
- Loading dock service stairs — short flights to dock height.
- Floor-to-grade exits — single-flight egress within OBC §3.4 constraints.
When a straight-run doesn't fit
- Rise > 16 risers (~9 ft) — code requires an intermediate landing; a switchback is more space-efficient.
- Limited horizontal run space — a 12 ft rise with a 7:11 tread ratio needs ~17 ft of horizontal room. Often switchback is shorter.
- Multi-level access — multiple destinations need separate flights or a switchback.
Typical parameters
- Rise range2 ft – 9 ft (single flight)
- Run lengthtypically 1.4× rise (per OBC tread/riser ratio)
- Width900 mm – 1100 mm typical (egress: occupant-load driven)
- Treadgrip-strut / bar-grate / checker-plate
- Guard height42" (OBC §3.3.1.18)
- Live load4.8 kPa + 1.3 kN concentrated
- Finishshop primer / galvanized / powder-coat
- Lead time3 – 5 weeks from sign-off
Related
- All steel stairs & industrial stair systems
- Switchback stairs — when rise exceeds single-flight
- Mezzanine access stairs — most common straight-run use case