Fire Stopping Services

Fire stopping systems are engineered passive fire protection assemblies that seal openings, penetrations, and joints in fire-rated walls, floors, and ceilings — restoring fire resistance and maintaining fire compartmentation to contain fire and smoke.

Fire stopping is the process of installing tested firestop materials at service penetrations and gaps in fire-rated construction — using sealants, collars, sleeves, boards, and intumescent products to achieve the required fire resistance rating.

Fire stopping maintains fire and smoke containment by closing pathways through fire-rated barriers. It prevents fire spread between compartments, protects escape routes, and ensures fire-rated assemblies perform as designed.

Firestop materials expand, char, or insulate when exposed to fire — sealing penetrations and joints. Intumescent firestop systems swell to fill voids; collars and sleeves crush plastic pipes; sealants and mortars form fire-resistant barriers at through penetrations.

Without fire stopping, every pipe, cable, and duct penetration becomes a breach in fire-rated construction. Proper firestop installation is essential for fire safety compliance, compartmentation systems integrity, and life safety in commercial and industrial buildings.

Fireproofing protects structural steel and large surfaces from heat exposure. Fire stopping seals specific openings — penetrations, joints, and gaps — in fire-rated walls and floors. Both are passive fire protection measures but address different parts of the building.

Passive fire protection is the broader category including fireproofing, fire-rated boards, barriers, and fire stopping. Fire stopping specifically refers to sealing penetrations and joints to maintain fire-rated assembly continuity.

Types include penetration firestop (pipes, cables, ducts), linear joint firestop (construction and expansion joints), head of wall firestop, perimeter and curtain wall firestop, and cavity barriers — each using certified firestop systems matched to the substrate and service.

Common firestop materials include firestop sealant, firestop foam, firestop mortar, firestop putty, firestop coating, firestop board, firestop wrap, firestop sleeve, firestop collar, and intumescent materials — selected per UL or ASTM listed system requirements.

Firestop sealant fills annular gaps around metal pipes, cables, and small penetrations in fire-rated walls and floors. It provides flexible, fire-resistant sealing where movement or vibration is expected at service penetrations.

Intumescent firestop systems expand significantly under heat to close voids around combustible pipes, cable bundles, and joints — providing fire resistance at penetrations where conventional sealants alone are insufficient.

A firestop collar is a metal band with intumescent liner fitted around plastic pipes where they pass through fire-rated floors or walls. In a fire, the liner expands to crush and seal the melting pipe, maintaining the fire-rated penetration.

A firestop sleeve is a factory-made or field-installed sleeve through a fire-rated barrier, packed with firestop material to allow services to pass while maintaining fire resistance. Pipe sleeve firestop systems are common in multi-penetration scenarios.

Pipe penetrations use tested systems — firestop sealant for metal pipes, firestop collars for plastic pipes, firestop mortar for large openings, or combination assemblies — sized to the annular space and fire resistance rating of the barrier.

Cable penetration firestop uses firestop putty, pillows, boards, or intumescent sealant around cable bundles and trays — maintaining fire-rated penetration integrity while allowing future cable additions where the system design permits.

Electrical firestop systems seal conduit, cable tray, and cable bundle penetrations using listed firestop materials — ensuring electrical conduit firestop and cable bundle firestop meet the fire resistance rating of the surrounding fire-rated wall or floor.

HVAC penetration firestop and duct penetration firestop use firestop boards, wraps, sealants, or damper-adjacent sealing at duct openings through fire-rated barriers — maintaining fire and smoke containment at mechanical service paths.

Gaps at construction joints, expansion joints, head of wall, and linear joints are sealed with firestop mortar, sealant, or board systems designed for joint movement — restoring fire-rated joints and perimeter firestop continuity.

Yes. Building fire codes and fire safety standards require fire stopping at penetrations and joints in fire-rated construction on virtually all commercial, industrial, and high-rise projects. Non-compliant firestop installation is a common inspection failure.

Key references include UL firestop systems listings, ASTM firestop systems test methods, NFPA requirements for fire-rated assemblies, and local building fire codes. OSISCO installs certified firestop systems with documented compliance records.

Firestop systems are tested in accredited laboratories — typically to ASTM E814/UL 1479 for penetrations and ASTM E1966/UL 2079 for joints — measuring fire resistance, hose stream, and where applicable, air leakage for smoke containment.

A fire resistance rating defines how long a wall, floor, joint, or penetration assembly resists fire exposure — commonly expressed in minutes (60, 90, 120, 180). Firestop must match or exceed the rating of the penetrated fire-rated assembly.

Compliance requires using a tested and listed system exactly as specified — correct material, annular space, backing, and installation method — plus firestop inspection, firestop documentation, and firestop testing records demonstrating the installed assembly matches the listing.