Fireproofing structural steel is important to ensure regulatory compliance, safety and structural integrity in the event of fire.
Steel is strong and durable but when it is exposed to high temperature, it loses its load-bearing capacity. To prevent structural failure various fireproofing methods are used to protect the steel components.
Before exploring the different types of fireproofing for steel, let us know why steel structure fireproofing is important.
Importance of Fireproofing steel structure
Steel is strong, versatile and cost-effective and is widely used in construction. However, when exposed to high temperatures, steel loses the majority of its strength and its load-bearing capacity. This makes fireproofing steel structures an important step in any steel-based construction project.
The fireproofing methods aim to insulate the steel structures; slow down heat transfer and prevent early failure during fire incidents. Steel structure fireproofing is important in high-rise buildings, industrial plants, warehouses and public infrastructures.
Fireproofing steel structure helps-
- Extend the time of Evacuation: Fireproofing gives the building’s occupants more time to escape during the sudden fire breakout.
- Maintain structural integrity: The firebreak out can weaken steel and fireproofing prevents the building from collapsing due to weakened steel.
- Safety Norms: By fireproofing the structural steel, one will ensure all the safety norms are maintained, and ensure compliance with local fire codes and building standards.
What are the various types of fireproofing steel structures?
- Vermiculite Coating: Vermiculite Coating is a type of cementitious fireproofing used to protect steel structures from fire. Vermiculite Coating is made from a lightweight mix of vermiculite, Portland Cement and other fire-resistant materials. It is applied as a spray-on layer. The coating when exposed to heat expands, creating an insulating barrier that slows down heat transfer to the steel. The vermiculite coating provides fire resistance for up to four hours, making it ideal for commercial buildings, industrial plants and high-rise structures. The coating is cost-effective, durable, and high-temperature resistant. This coating requires proper application and maintenance to prevent cracking and degradation with time.
- Intumescent Coatings: This coating is a thin film that expands to fifty times its original thickness when exposed to high temperatures. During a fire, the intumescent coating creates an insulating layer of char that protects the steel. The Intumescent Coating is applied like a paint-like coating and thus provides aesthetic appeal. The coating is lightweight and does not add any load to the structure. This coating is common in commercial and industrial buildings. They are apt for steel structures where appearance is important like restaurants or hotels. They are also used in bridges, stadiums, airports and high-rise buildings.
- Cementitious Fireproofing: Cementitious Fireproofing involves applying a layer of cement-based material to the steel surface, forming a fire-resistant and thick barrier. This type of coating is cost-effective when compared to intumescent coatings and provides fire resistance for up to four hours. The coating is used in refineries, industries and power plants. It is apt for hidden steel structures where aesthetics is unimportant or not a priority.
- Board Fireproofing: They are fire-resistant claddings installed around steel elements. Fire-resistant calcium silicate, gypsum or mineral-based boards are installed around steel members to provide insulation and prevent heat transfer. The board fireproofing provides a clean and fine finish. It offers excellent thermal insulation and can provide fire resistance for up to three to four hours. The board fireproofing is commonly used in office buildings, health care facilities and educational institutions. They are also used in projects where aesthetics matter.
- Spray-Applied Fire Resistive Materials: It is a lightweight, spray-applied mix of cement, gypsum, and mineral fibres that adheres to steel, providing insulation against fire. The spray applied fire can achieve fire resistance for up to four hours. It can also be quickly applied over large areas. This coating is effective for complicated steel structures. It is used in parking garages, warehouses and commercial structures. The spray-applied fire-resistive material is apt for hard-to-reach steel members.
- Fireproof Encasement: This is a concrete encasement involving surrounding steel structures with reinforced concrete or masonry. The encasement creates a thick fireproof barrier. The fireproof encasement provides excellent fire resistance for up to four or more than four hours. It offers an added structural strength. The fireproof encasement is durable and impact-resistant. It is used in power plants, industrial plants and tunnels. It is commonly used in critical infrastructure where fire safety is important.
How to choose fireproofing for the structural steel?
- Understand the Fire Codes: It is important to follow the local building codes and NFPA norms of fireproofing.
- Fire Risk Assessment: When choosing the fireproofing for structural steel, consider the fire exposure, load-bearing needs and structure type.
- Proper Application: It is important to ensure the proper- application of the fireproof coating. Incorrect application minimizes fireproofing effectiveness. It is advisable to work with a certified professional for installations.
- Regular Inspections: Fireproofing materials degrade over time. It is important to conduct routine maintenance to ensure their effectiveness. If required it is advisable to do the reapplication of fireproof coating.
- Aesthetic Needs: If the aesthetics of the building are important or for exposed steel, consider intumescent coating or fireproof boards.
- Protection from Moisture: It is important to protect the cementitious coatings and spray-applied materials from moisture. Professional service providers will advise with proper techniques to protect the coatings from moisture.
Fireproofing is an important safety measure for steel structures, protecting them from heat-induced failure and ensuring compliance with fire safety norms. By selecting the right fireproofing method, one can enhance building safety, protecting lives and extending structural durability in the event of fire.
FAQs
- What is a fireproofing steel structure?
Fireproofing steel structure is the application of protective materials to steel elements to delay heat transfer, prevent collapse during fire and maintain structural integrity. - What are the various methods of fireproofing steel structures?
The various methods of fireproofing steel structures include intumescent coatings, cementitious fireproofing, spray-applied fire resistive materials, concrete encasement, vermiculite coating and fireproof board encasement. - What is vermiculite coating?
Vermiculite Coating is a cementitious fireproofing material made from cement and vermiculite, providing thermal insulation and up to four hours of fire resistance for steel structures.