At SSE, we design hundreds of steel stairs each year for a wide range of projects. Steel stair design is one of our specialties and we work closely with miscellaneous steel fabricators to deliver stairs that meet both code and constructability requirements. Whether the need is for code-required egress, a striking architectural centerpiece, or heavy-duty industrial access, stairs demand careful detailing to ensure safety, compliance, and long-term performance.
In this guide, we cover the different types of steel stairs, critical design considerations, common code requirements, and industry references that can help structural engineers produce efficient, code-compliant designs.
Egress stairs are the most common type of steel stairs in buildings. These are typically switchback stairs located within shaft walls. The surrounding structure may be concrete shear walls or CMU masonry shear walls, with the stairs attached using embedded plates or post-installed anchors. In shafts framed with wood or light-gauge steel, it is common to use HSS steel posts within the walls to support the stair, or to use steel hangers to support the landing. These hangers are generally rods, angles, or HSS sections depending on the design and load requirements.
- Framing: Typically C or MC channels for stringers
- Treads and Landings: Commonly concrete on metal pans
- Landing Framing: Often light-gauge pans or form deck
Monumental stairs are architectural showpieces that often feature Architecturally Exposed Structural Steel (AESS) and high-end finishes.
- Framing: HSS stringers are common, as are built-up plate sections or channels, selected based on the architect’s aesthetic goals
- Railing: Decorative railings, glass, or cable systems are typical
- Special Note: When brittle materials such as glass, terrazzo, or tile are used, deflection control is critical to prevent cracking or damage. Vibration performance should also be evaluated to ensure comfort and durability in high-traffic areas.
These stairs function as their own structural system and are frequently located outdoors.
- Loading: Designed for building loads plus environmental loads such as seismic and snow
- Material Choice: Wide-flange columns and framing are preferred to simplify bolting and reduce the need for welding galvanized steel
- Treads and Landings: Commonly use grating or checker plate for drainage and durability
Used in manufacturing or industrial facilities, these stairs are generally not for public use.
- Design Codes: Often designed per OSHA guidelines instead of IBC requirements
- Materials: Grating for exterior stairs and checker plate for interior installations
- Focus: Durability, slip resistance, and function over aesthetics
The stair system must work seamlessly with the overall building structure. Verify that the supporting structure can carry both gravity loads (dead and live) and lateral loads (wind and seismic).
In seismic design categories C or D, ensure stairs remain stable under seismic loads and avoid unintentional bracing effects that could introduce unwanted axial loads into the building frame.
Steel stairs must be designed to safely carry a variety of loads as defined in ASCE 7:
- Dead Load: The self-weight of stair components, including stringers, treads, landings, railings, and any concrete fill
- Live Load: Typically 100 pounds per square foot for stairways, plus a concentrated load of 300 pounds applied at any point on the treads
- Wind Load: Required for exterior stairs and calculated based on the structure’s exposure category, height, and location
- Seismic Load: Applicable in seismic regions and based on the stair’s mass and connection to the building structure
- Snow Load: Applies to exterior stairs located in snow-prone regions, calculated according to local snow load values and ASCE 7 provisions
These loads ensure that stairs perform safely during normal use, emergency egress, and extreme environmental conditions.
- IBC defines rise, run, tread width, headroom clearance, maximum height between landings, and tread consistency
- Tread Width: Minimum clear width between stringers is strictly regulated
- Landing Requirements: Intermediate landings are required after a set number of risers to prevent excessive climbs without rest
- OSHA provides stair geometry requirements for industrial or manufacturing stairs that do not have public access, covering rise, run, tread surface, and handrail placement for workplace safety
- AISC Design Guide 34: Steel-Framed Stairway Design – Comprehensive guidance on steel stair design, including structural considerations, detailing practices, and code compliance.
- NOMMA (National Ornamental & Miscellaneous Metals Association) – Industry association providing best practices, resources, and technical support for ornamental and miscellaneous steel fabricators.
Steel stair engineering blends code compliance, structural performance, and practical constructability. From functional egress stairs designed for safe and efficient building circulation to monumental stairs that serve as a focal point in public spaces, each stair type comes with unique requirements for framing, materials, and connections. If you are a miscellaneous steel fabricator or structural engineer working on a stair project, our team has the experience and resources to deliver solutions that perform in the field and meet project schedules.
