High-rise buildings often experience significant dynamic displacement under extreme conditions such as earthquakes. Curtain wall systems, in particular, are more susceptible to gap failures due to their structural flexibility. A firestop system must not only ensure fire resistance but also accommodate multi-directional movement to maintain continuous fire separation. However, the current Taiwan CNS standards primarily address firestopping for penetrations like pipes and cables, lacking specific testing regulations for curtain wall gaps. This presents a significant safety risk.

As an internationally recognized inspection standard for firestop systems, ASTM E2393 establishes clear guidelines for firestopping in high-rise building curtain wall gaps. Below is an overview of the key requirements of this standard:

ASTM E2393 Inspection Standards

Scope of Inspection

This standard applies to all types of firestop systems and perimeter joint protection in buildings, including joints between fire-resistant structural components and between fire-rated floors and non-fire-rated walls.

Documentation Requirements

Inspectors must receive complete documentation at least ten working days before the inspection, including project specifications, contract drawings, approved designs, engineering judgments, manufacturer instructions, and applicable building codes.

Material Verification

• Inspectors must verify that firestop materials have been tested in accordance with ASTM E1966 or UL 2079 and comply with relevant standards.
• All materials must bear quality assurance labels from recognized certification bodies.

Construction Quality

• Firestop materials must be uniformly applied and securely bonded to the structural components.
• Inspectors should observe the installation process, document substrate and material measurements, or conduct destructive testing to verify compliance.

Dynamic Adaptability

• Firestop systems must maintain their sealing effectiveness under multi-directional displacement, such as those caused by earthquakes.
• Materials should have excellent flexibility, elongation, and fire resistance. Sufficient expansion space should be reserved at curtain wall joints to prevent cracks or detachment during seismic movement.

Fire Resistance Integrity

• Firestop materials must maintain their designed fire resistance rating even after structural vibrations.

Inspection Procedures

Inspection Frequency

The frequency of inspections depends on the method and project scope. It may include random inspections during installation or post-installation sampling.

Random Sampling During Installation

• Inspectors must randomly check at least 5% of firestop joint systems during the installation process.

Post-Installation Sampling

• A minimum of one sample per 500 linear feet of each joint system type must be inspected after installation.
• Destructive or disassembly verification methods should be used for validation.

Non-Compliance Handling

• If 10% or more of the inspected firestop systems fail to meet standards, the inspection should be halted. The installation team must correct or replace non-compliant systems before re-inspection.

Defect Documentation

• All identified defects must be recorded in inspection reports and reported to the contractor for corrective action.
• Repaired systems must undergo re-inspection within two days.

Final Report

• Upon completion of installation and inspection, the inspector must submit a final report detailing project information, inspector and installer credentials, and a summary of inspection results.

Design and Construction Recommendations

Based on the above requirements:

• Firestop materials should have excellent flexibility, elongation, and fire resistance.
• Sufficient expansion space should be reserved at curtain wall joints to prevent cracks or detachment during earthquakes.
• During construction, strict adherence to ASTM E2393 and other international standards is essential.
• Random inspections should be conducted to ensure firestop system effectiveness under extreme conditions.

Professional Inspection Services

As an IAS/iLac internationally accredited firestop inspection agency, Liansuo Construction Technology provides professional inspection services following ISO 17020 standardized procedures. We conduct comprehensive evaluations of firestop systems for curtain wall gaps in high-rise buildings and issue internationally certified third-party inspection reports based on ASTM E2393. Our reports offer technical guidance and rectification recommendations, effectively enhancing fire safety standards.

Conclusion

Firestop design for curtain wall gaps in high-rise buildings is a critical aspect of seismic and fire protection. Quality control must be maintained throughout material selection, structural design, construction, and on-site inspection. Liansuo Construction Technology, with its international certifications and extensive experience, is committed to bridging the gaps in Taiwan’s standards, reinforcing high-rise building seismic and fire protection, and safeguarding lives and property.