One technology doesn’t replace another; it complements. Books are no more threatened by Kindle than stairs by elevators.
– Stephen Fry
Stairs play a crucial role in architecture, offering vertical connectivity between floors in multi-story buildings while fulfilling a functional purpose. Stairs are a structure that allows movement between different levels by dividing the vertical distance into smaller, manageable steps.
Stairs encompass staircases, also called stairways, as well as escalators. Alternatives to traditional stairs include elevators (lifts), stair lifts, inclined moving walkways, ladders, and ramps.
This article aims to highlight key aspects of stair codes relevant to steel detailing.
1. INTRODUCTION
2. STAIR CODES AND THEIR IMPORTANCE
In the United States, stair detailing must adhere to various codes and standards to ensure safety, accessibility, and structural integrity. These regulations define essential aspects such as tread depth, riser height, handrails, and load-bearing requirements.
The International Code Council was established in 1994, with the goal of developing a single set of national model construction codes. It brought together three different organizations that had developed three separate sets of model codes throughout the U.S.: Building Officials and Code Administrators International, Inc. (BOCA), International Conference of Building Officials (ICBO) and Southern Building Code Congress International, Inc. (SBCCI).
The International Building Code (IBC) and International Residential Code (IRC) are model building codes developed by the International Code Council (ICC) that are adopted by many jurisdictions in the US to ensure public safety and welfare in the built environment. The IBC applies to most structures, while the IRC specifically addresses one- and two-family dwellings.
3. CODES AND STANDARDS USED IN STEEL DETAILING
The following codes are applied in stair detailing:
- IBC (International Building Code)
- IRC (International Residential Code)
- OSHA (Occupational Safety and Health Administration)
- ADA (Americans with Disabilities Act)
- PIP (Process Industry Practices)
1. IBC (International Building Code)
The IBC is a model building code that provides a comprehensive set of guidelines for the design, construction, and safety of buildings, with the goal of protecting public health, safety, and welfare.
Key IBC Requirements for Stairways:
- Width and Clearance: Defines minimum stairway width for safe passage.
- Tread and Riser Dimensions: Specifies uniform riser heights and tread depths for comfortable and secure movement.
- Handrails and Guardrails: Sets rules for placement, height, and design to enhance stability and prevent falls.
- Landing and Platforms: Regulates landing dimensions to provide resting points and safe transitions.
- Fire Safety and Egress: Ensures stairways support emergency evacuation routes with proper fire-resistant materials and signage.
- Accessibility Compliance: Aligns with ADA guidelines to accommodate users with mobility challenges.
2. IRC (International Residential Code)
The International Residential Code (IRC) sets safety and design standards for stairways in residential buildings, ensuring they meet structural, accessibility, and usability requirements. These guidelines help prevent accidents and improve comfort in homes.
Key IRC Stairway Regulations:
- Maximum Riser Height: Defines the height of each step to maintain consistency and ease of movement.
- Minimum Tread Depth: Ensures sufficient foot space for stability while ascending or descending.
- Handrail Requirements: Specifies height and graspability for added safety and support.
- Guardrail Standards: Prevents falls by establishing minimum railing height and spacing.
- Landing Dimensions: Regulates the size and placement of stair landings for safe transitions.
- Headroom Clearance: Ensures adequate overhead space to prevent obstructions.
These IRC rules play a crucial role in designing residential stairways that are both functional and compliant with safety standards.
3. OSHA (Occupational Safety and Health Administration)
The Occupational Safety and Health Administration (OSHA) is a U.S. government agency responsible for ensuring safe and healthy working conditions. Established in 1970 under the Occupational Safety and Health Act, OSHA sets regulations and conducts inspections to protect workers across various industries.
The Occupational Safety and Health Administration (OSHA) standard 1910.25 outlines safety requirements for stairways in workplaces to prevent accidents and ensure structural integrity. These regulations apply to various stair types, including standard, spiral, ship, and alternating tread stairs.
4. ADA (Americans with Disabilities Act)
The Americans with Disabilities Act (ADA) establishes accessibility standards for stairways to ensure safe and inclusive navigation for individuals with disabilities. These regulations apply to both interior and exterior stairs in public buildings and facilities.
Key ADA Stairway Requirements:
Uniform Step Dimensions: All steps must have consistent depth and height to prevent tripping hazards.
Step Height: Must be between 5 and 7 inches for accessibility.
Tread Depth: Minimum of 11 inches, measured from riser to riser, to provide secure footing.
Stair Width: Must be at least 36 inches to accommodate users safely.
Handrails: Required on both sides of stairways, positioned 34 to 38 inches above the stair nosing.
Nosings: Must not project more than 1.5 inches beyond the riser below to reduce tripping risks.
5. PIP (Process Industry Practices)
PIP Civil, Structural, and Architectural (CSA) Practices publishes essential CSA Engineering Design Practices, including specifications and fabrication/installation details.
This Practice provides fabrication and installation details for standard pipe railing for walking and working surfaces and for stair railing or handrail for egress. Although the details in this practice are intended to meet U.S. Occupational Safety and Health Administration (OSHA) requirements for process facilities, they may not meet the requirements of local or national building codes.
4. CONCLUSION
Building codes for stairs are established to enhance safety for all users, including children, the elderly, and individuals with disabilities.
They help minimize the risks of slips, trips, and falls while ensuring uniformity in design and construction for both contractors and homeowners.
The codes outlined above play a crucial role in stair design and construction, with periodic updates to accommodate evolving safety standards and requirements.
Reference:
- 2010 ADA standards for accessible design by department of justice (Americans with Disabilities Act 2010)
- AISC Design guide 34 – Steel framed stairway design by Adam D.Friedman S.E, P.E. (IBC and OSHA standards)
- ICC IBC (2012): International Building Code by International Code Consortium
- ICC IRC (2012): International Residential Code by International Code Consortium
- PIP STF05520 – STD – APR2002 – Details for Pipe Railing for Walking and Working Surfaces
- (OSHA) Standard Number 1910.25- Stairways -Walking-Working Surfaces
The miscellaneous information provided was highly beneficial.