What Fire Rating Can GRC Curtain Walls Achieve? Fire Rating Standards and Improvement Solutions

The fire rating of GRC curtain walls directly affects building fire safety and must comply with the requirements of the Code for Fire Protection Design of Buildings. It depends primarily on the fire performance of the GRC material itself and the fire-resistant structural design of the curtain wall. Clarifying fire rating standards and improvement paths is key to ensuring building fire safety. Drawing on 28 years of experience in fire protection projects, Qinglong analyzes the core points and practical solutions.

I. Basic Fire Rating Standards for GRC Curtain Walls

According to the Code for Fire Protection Design of Buildings (GB 50016-2014) and Glass Fibre Reinforced Cement (GRC) Decorative Products (JC/T940-2022), GRC material is itself a non-combustible material with a combustion performance rating of Class A, which is the fundamental fire protection advantage of GRC curtain walls. On this basis, the fire rating of a GRC curtain wall must be determined according to building height, usage function, and fire compartment division. Under normal conditions it can reach the B1 fire rating standard, and with proper structural design it can be upgraded to Class A. In the Shenzhen Pingshan High-tech Zone Comprehensive Service Center (Convention & Exhibition Center + Hotel) project, Qinglong's GRC curtain wall achieved the Class A fire rating through optimized design, meeting the fire protection requirements for high-rise buildings. Different building types have different fire rating requirements: super high-rise buildings (height >100m) must reach Class A, while high-rise buildings must reach B1 or above.

II. Core Factors Affecting the Fire Rating

The fire rating of GRC curtain walls is affected by core factors such as material performance, structural design, and sealing materials. In terms of materials, GRC aggregates must use non-combustible minerals (such as quartz sand) and avoid adding combustible impurities. Qinglong's GRC materials use 100% inorganic components to ensure Class A non-combustible performance. In terms of structural design, fire isolation belts must be installed at the boundaries of fire compartments, filled with fire-resistant rock wool (combustion performance Class A) with a width ≥500mm to block flame spread. In the Wuhan Han Show Theater project, Qinglong effectively divided fire compartments through fire isolation belt design. In terms of sealing materials, fire-resistant sealant (temperature resistance ≥1000℃) must be used instead of ordinary silicone sealant to avoid toxic gases produced by sealant combustion at high temperatures. In the Hainan Changying Global 100 Fantasy Park project, the use of fire-resistant sealant improved the curtain wall's overall fire performance.

III. Core Technical Solutions for Improving the Fire Rating

Through targeted technical optimization, the fire rating of GRC curtain walls can be effectively improved to Class A. In terms of component optimization, increase the GRC panel thickness to 25-30mm with built-in steel mesh or fire-resistant fibers to enhance high-temperature resistance. Qinglong's test data show that 25mm thick GRC panels can withstand 800℃ high temperatures for 1.5 hours without collapsing. In terms of joint fire protection, connectors are treated with fire-retardant coatings (fire resistance limit ≥1.5h) to prevent connector failure at high temperatures, while gaps between components and the main structure are filled with fire-stopping materials to form a sealed fire barrier. In terms of system design, a composite structure of "GRC panel + fireproof insulation layer + fireproof backing panel" is adopted to enhance the overall fire resistance limit. In the Shenzhen Longhua Xiangshan Science and Technology Park project, this composite structure achieved a curtain wall fire resistance limit of 2.0h, meeting Class A fire protection requirements. In addition, fire protection materials should be regularly inspected and replaced to ensure long-term stable fire performance.

IV. Fire Rating Testing and Acceptance Standards

Fire ratings must be verified through professional testing to ensure compliance with design requirements. Testing items include material combustion performance (GB/T 8624) and curtain wall fire resistance limit (GB/T 20284), with test reports issued by authoritative third-party institutions. All of Qinglong's GRC curtain wall projects come with complete fire protection test reports. On-site acceptance requires inspection of key aspects such as fire isolation belt installation, fire-resistant sealant application, and fire-stopping integrity to ensure construction meets design requirements. During the operation and maintenance phase, fire performance re-inspection is conducted every 3 years to check for aging and detachment of fire protection materials and to promptly replace damaged components. In the Shanghai Qingpu R&D and Production project, Qinglong ensured that the GRC curtain wall maintained Class A fire performance long-term through regular fire protection operation and maintenance, providing reliable protection for building safety.