Fire Sealant Applications Guide

Fire sealants are critical components in maintaining fire compartment integrity. Even the highest-rated fire walls are compromised if penetrations and joints are not properly sealed. This guide covers fire sealant types, applications, and installation best practices.

Understanding Fire Sealants

Fire sealants are designed to maintain fire resistance in joints, penetrations, and gaps:

• Intumescent: Expand when heated to seal gaps and penetrations
• Endothermic: Absorb heat and release water during combustion
• Fire Rated: Tested to specific time ratings (1, 2, 3, 4 hours)
• Smoke Seals: Prevent smoke passage at ambient temperatures

Types of Fire Sealant Products

Intumescent Sealants

The most common fire sealant type. When exposed to fire, intumescent materials expand to fill gaps and create an insulating char. Available in acrylic, silicone, and hybrid formulations. GUIBAO 995 sealant is a popular acrylic intumescent option.

Silicone Sealants

Flexible sealants suitable for expansion joints and moving applications. Silicone formulations offer excellent temperature resistance and remain flexible after curing. Typically used where movement accommodation is required.

Putty Pads and pillows

Pre-formed fire blocking products for cable and pipe penetrations. Putty pads wrap around electrical boxes; pillows compress into larger openings. Both provide quick installation for repetitive penetrations.

Common Applications

Penetration Sealing

Pipes, cables, and conduit passing through fire-rated walls require sealing:

• Plastic pipes (with intumescent collars or wrap)
• Metal pipes and conduit
• Electrical cables and cable trays
• HVAC ductwork (with fire dampers)

Joint Sealing

Construction joints in walls and floors:

• Floor-to-wall joints
• Wall-to-wall joints (head-of-wall)
• Expansion joints in concrete
• Precast panel joints

Door Frame Sealing

The gap between door frames and surrounding walls must be sealed:

• Frame-to-wall perimeter
• Under threshold gaps
• Hardware cutout sealing

Installation Guidelines

Proper installation is critical for fire sealant performance:

• Clean surfaces before application; remove dust, oil, and debris
• Ensure substrates are properly supported
• Apply sealant to proper depth per manufacturer specifications
• Use backer rod for joints deeper than specification allows
• Tool sealant for proper adhesion and appearance

Fire Rating Requirements

Sealant ratings must match or exceed the wall assembly rating:

• 2-hour walls: Minimum 2-hour sealant rating
• 3-hour walls: Minimum 3-hour sealant rating
• 4-hour walls: Minimum 4-hour sealant rating

Product Selection

Select sealants based on application requirements and pair with our fire doors for complete fire protection.

Select sealants based on application requirements:

• Substrate: Concrete, metal, wood, or plastic
• Movement: Static joint or dynamic expansion joint
• Exposure: Interior or exterior application
• Rating: Required fire resistance rating
• Certification: Third-party testing and listing

Maintenance and Inspection

Fire sealants require periodic inspection:

• Annual visual inspection of all sealed joints
• Check for cracks, delamination, or damage
• Verify sealant remains properly bonded
• Document inspection findings

Professional Installation

For critical applications, engage firestop specialists certified by recognized industry programs. Contact our team for recommendations on fire sealant products and qualified installers.

Browse our fire sealant products including intumescent sealants and penetration seals for comprehensive fire protection.