Fire can cause severe structural damage if the building is not properly designed to meet safety standards. Fire resistance standards in steel building design exist to protect occupants, safeguard property, and ensure compliance with codes.
In this blog, we’ll explore the key fire resistance standards you need to know, why they matter, and how they are applied in real steel building projects.
Are Steel Building Designs Prone to Fire?
Steel is non-combustible, meaning it does not catch fire. However, when exposed to extremely high heat, it begins to lose strength and stiffness. At around 1,100°F (593°C), steel can lose about half of its load-bearing capacity, and at 2,000°F (1,093°C), it may fail completely.
This makes fire resistance planning essential. Without protective measures, a steel building could collapse quickly. Standards exist to delay this outcome, giving occupants more time to escape and firefighters time to act.
Fire Resistance Standards in Steel Building Design
Here are some of the most important fire-resistant standards that must be observed during steel building design.
1. Standard Fire Ratings: How Steel Elements Are Tested
Fire resistance is measured by fire ratings, which indicate how long a material or assembly can withstand fire exposure while maintaining structural integrity. Ratings are typically expressed in hours, such as 1-hour, 2-hour, or 3-hour fire resistance.
Testing involves placing structural elements (like steel beams or columns) in a furnace to simulate fire conditions. The element is monitored for structural failure, temperature rise, and integrity. The results determine whether it meets the required fire resistance rating set by codes.
2. The Role of Building Codes
Fire resistance standards are not optional; they are required by codes for steel building design. The most commonly followed guidelines in the U.S. are provided by:
• International Building Code (IBC): Sets minimum fire resistance ratings for different building types, occupancies, and heights.
• National Fire Protection Association (NFPA): Publishes standards like NFPA 5000, which cover fire protection in construction.
• ASTM Standards (American Society for Testing and Materials): Define test methods for fire resistance of materials and assemblies.
By following these codes, steel buildings can ensure compliance and avoid legal or safety issues.
3. Fire Resistance of Structural Steel Members
Each part of a steel building design has different fire resistance requirements depending on its role in supporting the structure:
• Columns: Carry vertical loads and are critical for stability. They usually need the highest fire resistance rating.
• Beams: Support floors and roofs; their fire protection ensures structural continuity.
• Floor Systems: Tested as assemblies, since they combine steel decking, concrete, and insulation.
Standards ensure these members can perform long enough during a fire to prevent sudden collapse.
4. Fire Resistance Standards for Walls and Partitions
It’s not just the steel frame that matters; walls, partitions, and enclosures also need fire ratings. Fire-rated assemblies prevent flames and smoke from spreading between different parts of the steel building design. Standards often require:
• Fire-rated exterior walls to stop fire from spreading to nearby buildings.
• Fire-rated interior partitions to protect escape routes and critical areas.
• Fire-resistant floor and ceiling assemblies to block vertical fire spread.
By combining steel protection with rated partitions, a building achieves full fire safety.
5. Fire Resistance Standards for Roofing Systems
Steel roofing systems also need to be tested for fire resistance. Roof assemblies may be exposed to external fires, such as wildfires, or internal fires pushing heat upward. Standards like UL 790 set performance criteria for fire exposure on roof coverings.
A roof with proper ratings ensures fire does not penetrate or spread rapidly across the structure.
6. Passive vs. Active Fire Protection in Steel Buildings
Fire safety in steel building design is often a mix of passive and active systems:
• Passive Fire Protection (PFP): Built-in measures like fireproof coatings, rated walls, and protected structural members. They work automatically without activation.
• Active Fire Protection (AFP): Systems like sprinklers, alarms, and extinguishers that require detection or human action.
Standards ensure both are included, since they work best together. For example, coatings slow down structural damage while sprinklers control fire growth.
7. International Fire Resistance Standards
Fire resistance standards vary by region, but the goal is always the same: safety. Some widely recognized ones include:
• ISO 834 (International): Standard fire curve for testing resistance of building materials worldwide.
• BS 476 (UK): Provides fire test methods for structural steel and assemblies.
• EN 13501 (Europe): Classification of fire performance in construction products.
Global steel projects must comply with the appropriate local standards, or multiple ones if designed for international use.
8. Protective Methods to Improve Fire Resistance
Since bare steel building design alone cannot resist fire for long, additional protective methods are used. Common solutions include:
• Spray-Applied Fire-Resistive Materials (SFRM): A cost-effective spray coating that insulates steel from high heat
• Intumescent Coatings: Special paints that expand when exposed to heat, forming a protective char layer.
• Concrete Encasing: Surrounding steel with concrete to slow down heat penetration.
• Board Systems: Using fire-rated boards to cover steel sections.
The choice depends on the building type, budget, and appearance requirements.
Why Fire Resistance Standards Protect More Than Just the Building
Fire resistance is not only about protecting the steel building design; it’s also about saving lives and reducing losses. Meeting standards helps:
• Protect Occupants: Fire-rated designs give people more time to evacuate safely.
• Support Firefighters: Stronger structures reduce collapse risk during firefighting operations.
• Lower Insurance Costs: Buildings with high fire resistance often qualify for reduced insurance premiums.
• Preserve Investment: Delaying collapse helps minimize property damage and business interruptions.
These benefits make fire resistance an essential part of steel building design.
Wrap Up
Fire resistance standards are a critical part of steel building design. They ensure that steel structures can stand strong under high heat, protecting both people and property. By following codes and using protective methods, builders can extend the fire resistance of steel members and assemblies.
These standards create a comprehensive safety net, and Seven Peaks Steel strictly adheres to them. We believe fire resistance in steel building design is not just about meeting regulations, it’s about safeguarding lives, assets, and long-term investments. Schedule your appointment today!