SynC · SynC Standards

Firestopping

Rev3
IssuedJun 8, 2026

Revision history

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1 Scope

NOTE This standard governs the materials, configuration, installation, identification, and inspection of through-penetration firestop systems and fire-resistive joint systems in fire-resistance-rated and smoke-resistant assemblies. (1.1)
NOTE Firestopping restores the fire-resistance and smoke-resistance performance of a rated assembly wherever that assembly is interrupted by a penetration or a movement joint. (1.2)
1.3 Every opening in a rated wall or floor for a pipe, conduit, cable, duct, sleeve, or service penetration, and every linear gap between rated assemblies or between a rated assembly and an adjacent construction, shall be closed with a tested and listed system that has been evaluated to the same hourly rating as the assembly it interrupts.
NOTE Firestopping is a system of components — a tested combination of base assembly construction, penetrating item characteristics, annular space geometry, packing materials, and sealing materials — evaluated together in accordance with UL 1479 (for through-penetrations) or UL 2079 (for joints) and listed by a qualified testing agency. (1.4)
NOTE A change to any component of the listed system can invalidate the rating. (1.5)
1.6 Substitution of products, dimensions, or installation details outside the limits of the listed system shall not be permitted without a written engineering judgment from the firestop manufacturer's qualified engineer or a registered design professional.
1.7 The Contractor shall execute firestopping as a coordinated trade with the responsibilities of all penetrating trades (mechanical, electrical, plumbing, communications, and life safety) clearly defined.
1.8 Penetrating trades shall coordinate the sizing of openings and the locations of penetrations with the firestop scope.
1.9 Penetrating trades shall not enlarge, reposition, or alter penetrations after firestopping is installed without re-firestopping the modified opening.
1.10 Coordinate this scope with Gypsum Board Assemblies for the assemblies into which firestopping is installed, with Doors Frames And Hardware for openings filled by rated door assemblies, with Fireproofing for structural fire protection that is a separate scope from firestopping, with Raceways And Conduit for electrical penetrations, with Hvac Ductwork for mechanical penetrations and damper sleeves, and with Sanitary Waste And Vent Piping and Domestic Water Piping for plumbing penetrations.

2 Referenced Standards

2.1 All materials, systems, and installation shall comply with the latest edition adopted by the Authority Having Jurisdiction for each of the following standards.
2.2 Where the contract documents or a referenced standard impose a more stringent requirement than the minimum of any other standard, the more stringent requirement governs unless the Architect of Record directs otherwise in writing.

2.3 Referenced Standards Table

Standard Title
UL 1479 Fire Tests of Through-Penetration Firestops
UL 2079 Tests for Fire Resistance of Building Joint Systems
ASTM E814 Standard Test Method for Fire Tests of Penetration Firestop Systems
ASTM E1966 Standard Test Method for Fire-Resistive Joint Systems
ASTM E84 Standard Test Method for Surface Burning Characteristics of Building Materials
ASTM E119 Standard Test Methods for Fire Tests of Building Construction and Materials
ASTM E2174 Standard Practice for On-Site Inspection of Installed Penetration Firestops
ASTM E2393 Standard Practice for On-Site Inspection of Installed Fire Resistive Joint Systems and Perimeter Fire Barriers
ASTM E2307 Standard Test Method for Determining Fire Resistance of Perimeter Fire Barriers Using Intermediate-Scale, Multi-story Test Apparatus
IBC International Building Code, Chapter 7 — Fire and Smoke Protection Features
IFC International Fire Code (current edition adopted by jurisdiction)
NFPA 101 Life Safety Code
NFPA 5000 Building Construction and Safety Code
FM 4990 Approval Standard for Firestop Contractors
FM 4991 Approval Standard for Firestop Contractors (Installer Certification)
UL Fire Resistance Directory UL Listed Through-Penetration and Joint Firestop Systems
IFC Manual International Firestop Council, Manual of Practice for Firestopping
NOTE UL 1479 and ASTM E814 are technically equivalent test methods for through-penetration firestops; products evaluated under either standard are accepted by the International Building Code. (2.4)
NOTE UL 2079 and ASTM E1966 are the equivalent test methods for fire-resistive joint systems. (2.5)
NOTE The International Firestop Council publishes industry guidance on the design, installation, and inspection of firestop systems and is referenced for best-practice procedures not codified in the test standards. (2.6)

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following for the Architect's review prior to procurement and installation:
  • Product data for each firestop product proposed, including manufacturer's published installation instructions, applicable UL system numbers, F and T ratings, smoke L rating where applicable, and ASTM E84 flame-spread and smoke-developed indices
  • Listed system schedule cross-referencing every penetration type and joint condition shown on the drawings to a specific UL or equivalent tested system number, including the test agency, system number, F rating, T rating, L rating, and joint movement class as applicable
  • Engineering judgments (EJs) for any field condition not addressed by a published listed system, prepared and signed by a qualified engineer employed or contracted by the firestop manufacturer or by a registered design professional, with the basis of the judgment clearly stated and the referenced tested systems identified
  • Installer qualification documentation including FM 4991 approval, UL Qualified Firestop Contractor Program enrollment, or manufacturer training certifications for the specific products proposed
  • Sample of the firestop identification label proposed for installed systems
  • Coordination drawings identifying the location and type of every through-penetration and joint firestop system, organized by floor, room, and assembly type
Action Submittals Requiredcheckbox
Product data — each firestop product
Listed system schedule (penetrations and joints)
Engineering judgments for non-listed conditions
Installer qualification documentation
Sample identification label
Coordination drawings
3.1.2 Installation of any firestop system shall not begin until the corresponding submittals have been reviewed and returned.

3.2 Closeout Submittals

3.2.1 The Contractor shall provide the following at project closeout:
  • As-installed firestop system schedule with each system identified by location, system number, and date installed
  • Photographic record of representative installations of each system type prior to concealment
  • Field inspection reports per ASTM E2174 for through-penetrations and ASTM E2393 for joints, where inspection was performed
  • Warranty documentation for all firestop products carrying a manufacturer warranty
  • Manufacturer's maintenance instructions covering repair, modification, and re-firestopping of existing systems
Closeout Submittals Requiredcheckbox
As-installed firestop system schedule
Photographic record of representative installations
Field inspection reports (ASTM E2174 / E2393)
Warranty documentation
Manufacturer maintenance instructions

4 Quality Assurance

4.1 Installer Qualifications

Installer Qualification Requiredradio
FM 4991 approved firestop contractor
UL Qualified Firestop Contractor Program enrolled
Manufacturer certified installer (each product line)
Any of the above acceptable
4.1.1 Firestop installation shall be performed by a contractor qualified in firestop work and trained on the specific products proposed.
4.1.2 The Contractor shall hold one or more of the following qualifications: FM 4991-approved firestop contractor; UL Qualified Firestop Contractor under the UL Qualified Firestop Contractor Program; or manufacturer-certified installer for each product line installed, with current training certificates available on site.
4.1.3 Firestop work shall not be assigned to general labor, to penetrating trades performing incidental closure of their own openings, or to contractors without the qualification required for the work.

4.2 Single-Source Responsibility

Single-Source Manufacturer Requiredradio
Yes — all firestop products from one manufacturer
Multiple manufacturers permitted with compatibility documentation
4.2.1 To the maximum extent practical, all firestop products on the project shall be obtained from a single manufacturer with a complete product line covering through-penetrations, joints, and special conditions.
NOTE Single-source responsibility reduces the risk that adjacent firestop systems are installed with incompatible chemistries — for example, a silicone sealant in one system and an acrylic sealant in an adjacent system, where the cure of one product is inhibited by contact with the uncured material of the other. (4.2.2)
4.2.3 Where products from more than one manufacturer are unavoidable, the Contractor shall provide written confirmation from each manufacturer that the products are compatible at the conditions in which they will adjoin.

4.3 Pre-Installation Conference

4.3.1 Before firestop installation begins, the Contractor shall hold a pre-installation conference with the Owner's representative, the Architect, the firestop subcontractor, the penetrating trade subcontractors, and the special inspector (where one is engaged).
4.3.2 The conference shall review the firestop submittal schedule, the listed system numbers, engineering judgments, sequencing constraints, the identification labeling protocol, and the field inspection procedures.
4.3.3 Coordination between firestop and penetrating trades shall be resolved at or before this conference, not in the field after openings are made.

4.4 Field Mock-Up

Mock-Up Requiredradio
Yes — one of each major penetration and joint type
No
4.4.1 Where the contract documents require a mock-up, the Contractor shall install one representative through-penetration system for each major penetrant category (metallic piping, non-metallic piping, electrical cable, conduit, cable tray) and one representative joint system for each joint condition (head-of-wall, wall-to-wall, floor-to-floor) at locations directed by the Architect.
4.4.2 The mock-ups shall remain in place for review before production installation proceeds and shall demonstrate the materials, packing depth, annular space treatment, sealant thickness, surface tooling, and identification label exactly as the production work will be executed.

4.5 Field Inspection by Special Inspector

NOTE The International Building Code requires special inspection of through-penetration firestop systems and fire-resistive joint systems in high-rise buildings and in buildings of certain occupancy classifications. (4.5.1)
Third-Party Special Inspection Requiredradio
Yes — per ASTM E2174 (penetrations) and ASTM E2393 (joints)
No — not required by code or contract
4.5.2 Where special inspection is required by code or by the contract documents, the special inspector shall inspect installations in accordance with ASTM E2174 (through-penetrations) and ASTM E2393 (joints).
NOTE Both standards prescribe a destructive sampling rate (typically a percentage of installations or a minimum number per floor) and a visual inspection of all accessible installations. (4.5.3)
4.5.4 Inspections shall be conducted before the firestop system is concealed by finishes or by subsequent construction.

5 Environmental and Service Conditions

5.1 Substrate and Ambient Conditions During Installation

Minimum Ambient Temperature During Installationrange
°F
4050
Default: 40 °F
5.1.1 Firestop products shall be installed only when ambient and substrate temperatures, humidity, and substrate moisture content fall within the ranges published by the manufacturer for the specific product.
NOTE Most water-based firestop sealants require ambient and substrate temperatures above 40 °F (4 °C) during installation and through the initial cure period; setting-type mortars and intumescent compounds may have wider operating ranges. (5.1.2)
5.1.3 The Contractor shall verify the published limits for each product and shall provide temporary heat, dehumidification, or ventilation as necessary to maintain acceptable conditions.
5.1.4 Substrates shall be clean, dry, frost-free, and free of oil, grease, form-release agents, loose material, dust, and any contaminant that would impair adhesion.
5.1.5 Concrete substrates shall be cured per the concrete manufacturer's instructions before sealant application.
NOTE Uncured concrete continues to release moisture and alkali that can prevent sealant adhesion or accelerate sealant degradation. (5.1.6)

5.2 Protection of Installed Firestopping

5.2.1 Installed firestop systems shall be protected from physical damage, water intrusion, and contamination until the building is enclosed and substantially complete.
NOTE Sealant joints subjected to physical disturbance during cure can develop bond-line failures that are not visible from the surface but that compromise the rated performance. (5.2.2)
5.2.3 Damaged or disturbed firestop systems shall be cut out and replaced with new material to the full system depth.

5.3 Service Temperature and Movement

5.3.1 Firestop systems shall be selected for the service environment to which they will be exposed.
5.3.2 Exterior-rated systems shall be provided for any firestop installed at the building envelope or at locations subject to exterior exposure during or after construction.
5.3.3 High-temperature service applications — boiler rooms, kitchen exhaust shafts, and similar locations with sustained elevated service temperatures — shall use firestop systems specifically tested at the service temperature in addition to fire exposure.
5.3.4 Joints subject to seismic or thermal movement shall be filled with systems tested at the design movement class.

6 Ratings and Performance

6.1 F Rating

NOTE The F rating is the fire-resistance rating of the through-penetration firestop system, measured as the duration in hours during which the system prevents flame passage and resists hose-stream impact at the conclusion of the fire test under UL 1479 or ASTM E814. (6.1.1)
Required F Ratingselect
1 hour
1.5 hours
2 hours
3 hours
4 hours
Per drawings
6.1.2 The F rating of the installed system shall equal or exceed the fire-resistance rating of the assembly being penetrated.
NOTE A two-hour rated wall requires a minimum two-hour F-rated through-penetration system at every penetration. (6.1.3)

6.2 T Rating

NOTE The T rating measures the duration during which the temperature rise on the unexposed side of the firestop system — including the temperature of any penetrating items at a defined distance from the unexposed face of the assembly — remains below 325 °F (163 °C) above ambient. (6.2.1)
Required T Ratingselect
Not required (wall penetration, no combustibles within 1 in of unexposed side)
Equal to F rating (floor penetration, IBC requirement)
1 hour
2 hours
3 hours
Per drawings
NOTE The T rating is a measure of thermal transmission through the penetrant itself, not only through the firestop materials. (6.2.2)
6.2.3 The T rating is required by the International Building Code wherever the penetration is located in a fire-rated floor or floor-ceiling assembly, where combustibles on the floor above could be ignited by heat conducted through the penetrant, and at any penetration where combustible materials are within 1 inch of the unexposed side.
6.2.4 A T rating equal to the assembly rating is required at floor penetrations; in walls, a zero T rating is typically acceptable where no combustibles are adjacent.
NOTE Metallic pipes and conduits readily conduct heat and therefore reduce the T rating of a firestop system below its F rating. (6.2.5)
NOTE Achieving a high T rating around metallic penetrants generally requires either a thicker firestop system, additional insulation wrap, or selection of a different listed system with the required T rating. (6.2.6)

6.3 L Rating (Air and Smoke Leakage)

NOTE The L rating quantifies the air leakage through the through-penetration firestop system at ambient temperature and at 400 °F (204 °C), expressed in cubic feet per minute per square foot of opening area at a pressure differential of 0.30 inch water column. (6.3.1)
L Rating Required (Smoke Barrier)radio
Yes — maximum 5.0 CFM/sq ft at ambient and 400 °F
Yes — project-specific limit per drawings
No — not in smoke barrier
Per drawings
6.3.2 The L rating is required by the International Building Code at penetrations of smoke barriers and smoke partitions, including the smoke-resistant construction enclosing corridors, exit access stairs, and smoke compartment boundaries in healthcare and other occupancies where smoke containment is a life safety objective.
6.3.3 The maximum permitted L rating depends on the application: 5.0 CFM/sq ft at both ambient and 400 °F for most smoke-barrier applications under the IBC.

6.4 W Rating (Water Resistance)

NOTE The W rating indicates that the through-penetration firestop system has been tested and listed to resist water leakage at a defined hydrostatic pressure for a defined duration prior to fire testing. (6.4.1)
W Rating Requiredradio
Yes — required at all floor penetrations
Yes — required at floor penetrations in wet areas only
No
Per drawings
6.4.2 A W rating is required at horizontal penetrations through floors in spaces where standing water from fire department hose streams, fire sprinkler discharge, plumbing leaks, or wet construction (such as floors above swimming pools, mechanical penthouses, or kitchens) could pond above the penetration and migrate to the floor below.

6.5 Joint Movement Class

Joint Movement Classselect
Class I — less than 5% joint movement
Class II — 5% to 12.5% joint movement
Class III — greater than 12.5% joint movement
Not applicable — penetration, not joint
Per drawings
Joint Movement Cycles Tested (UL 2079)select
500 cycles (standard)
Per listed system requirements
6.5.1 Fire-resistive joint systems shall be tested at the maximum percentage of joint movement that the system will experience in service.
NOTE UL 2079 cycles the joint test specimen at the rated movement class — typically expressed as a percentage of the joint width, such as Class I (movement less than 5%), Class II (movement 5% to 12.5%), or Class III (movement greater than 12.5%) — for a defined number of cycles prior to fire exposure. (6.5.2)
NOTE A joint system installed in a joint whose actual movement exceeds the tested class will fail to maintain its rating after building cycling. (6.5.3)
NOTE Head-of-wall joints where the wall meets a fixed deck typically have minimal movement and qualify under Class I. (6.5.4)
6.5.5 Head-of-wall joints with deflection heads at the top of the wall shall accommodate the structural live-load deflection and may require Class II or Class III systems depending on the deck depth and span.
NOTE Building expansion joints, seismic joints, and the curtain-wall-to-floor "perimeter fire barrier" gap typically require the highest movement class. (6.5.6)

7 Through-Penetration Firestop Systems

7.1 General Through-Penetration Requirements

Assembly Type (Penetration Location)radio
Fire-resistance-rated gypsum wall
Fire-resistance-rated concrete or masonry wall
Fire-resistance-rated concrete floor
Fire-resistance-rated composite metal deck floor
Smoke barrier (rated or non-rated)
Per drawings
7.1.1 Every penetration of a fire-resistance-rated wall, floor, floor-ceiling assembly, or roof-ceiling assembly by a pipe, conduit, cable, sleeve, duct, or other service item shall be sealed with a tested and listed through-penetration firestop system meeting the F rating and, where required, the T, L, and W ratings of the assembly.
7.1.2 The selected system shall be listed by an approved testing agency (UL, FM, Intertek, or another nationally recognized testing laboratory) and shall match the field condition within the parameters defined in the system listing: the assembly type and rating, the penetrant material and size, the maximum and minimum annular space, the maximum penetrant projection from the assembly, and any insulation or covering on the penetrant.

7.2 Penetrant Types

NOTE The selection of a firestop system is driven primarily by the type and size of the penetrating item. (7.2.1)
NOTE Each major category of penetrant has distinct fire behavior and therefore requires a system designed for that behavior. (7.2.2)
Penetrant Typeradio
Metallic pipe (steel, copper, cast iron, ductile iron)
Non-metallic pipe (PVC, CPVC, ABS, PEX)
Electrical conduit (EMT, IMC, rigid steel)
Insulated metallic pipe
Single or grouped electrical cables
Cable tray or ladder
Bus duct
HVAC duct (with damper or sleeve)
Sleeve only (no penetrant)
Blank opening (future use)
Mixed penetrants (multiple types in single opening)
Per drawings
NOTE Metallic pipe and conduit conduct heat readily and produce no combustion gases of their own, but they do transmit heat to the unexposed side and to insulation or combustibles in contact with them. (7.2.3)
NOTE Non-metallic pipes — PVC, CPVC, ABS — soften, char, and burn in fire; non-metallic pipe firestop systems rely on intumescent collars, wrap strips, or putty pads that expand under heat to crush the softened pipe and close off the opening. (7.2.4)
7.2.5 Insulated metallic pipes combine the heat transfer of metal with the potential for the insulation to combust, melt, or fall away, and shall use systems tested with the specific insulation type and thickness in place.
7.2.6 Systems for cables shall limit the total cross-sectional area of cable to a defined percentage of the opening and require packing materials between cables.

7.3 Annular Space

NOTE The annular space is the gap between the penetrant and the edge of the opening through the assembly, and is one of the most important variables in the selection of a listed system. (7.3.1)
Minimum Annular Space (Listed System Range)range
in
02
Maximum Annular Space (Listed System Range)range
in
0.256
Default: 2 in
NOTE Listed systems define a minimum and a maximum annular space; an installed condition outside that range, even by a small margin, does not comply with the listing. (7.3.2)
7.3.3 The Contractor shall verify the annular space at every penetration before installing firestop materials.
7.3.4 Where field conditions produce annular spaces outside the listed range, an alternative listed system shall be selected or an engineering judgment shall be obtained.
7.3.5 The point-contact condition — a penetrant touching the edge of the opening with zero annular space at one or more locations — is permitted only when the listed system specifically allows point-contact.
7.3.6 The Contractor shall not assume that a penetrant centered in an opening can be allowed to drift to point-contact at one side.

7.4 Sleeves

NOTE Sleeves are used at floor penetrations to provide a finished edge to the opening, to support the penetrant during construction, and to allow the firestop material to be installed flush with the floor surface. (7.4.1)
Sleeve Used at Floor Penetrationradio
Yes — steel sleeve cast in slab
Yes — steel sleeve grouted in core-drilled opening
No — core-drilled opening without sleeve
Per drawings
Sleeve Height Above Finished Floorrange
in
04
Default: 2 in
7.4.2 Sleeves shall be steel, galvanized or paint-coated, set in the floor before concrete placement, or core-drilled and grouted in place after placement.
7.4.3 The sleeve shall be a part of the listed firestop system; sleeves of dimensions or materials outside the listed system invalidate the rating.
7.4.4 Sleeves shall extend a minimum height above the finished floor as required by the listed system (typically 1 to 4 inches for floor penetrations) and shall extend through the full thickness of the floor.
7.4.5 The space between the sleeve and the surrounding concrete shall be sealed with concrete during placement or with non-shrink grout in core-drilled conditions.

8 Firestop Materials

8.1 Material Types

NOTE Firestop materials fall into several categories defined by their composition and fire-response mechanism. (8.1.1)
NOTE The selection among them is determined by the listed system, not by the Contractor's preference. (8.1.2)
Sealant Material Typeradio
Intumescent sealant
Elastomeric (non-intumescent) sealant
Endothermic sealant
Intumescent latex
Silicone sealant
Acrylic latex sealant
Per listed system
NOTE Intumescent products expand when heated, typically beginning at 250 °F to 350 °F (121 °C to 177 °C), forming a char that crushes softening penetrants and seals the opening. (8.1.3)
8.1.4 Intumescent sealants shall be used at penetrations by non-metallic pipes (PVC, CPVC, ABS) because the pipe softens and the intumescent must expand to close the void left by the pipe.
NOTE Endothermic products contain chemically bound water that is released as a heat-absorbing reaction at elevated temperatures, reducing temperature transmission and protecting the surrounding system. (8.1.5)
NOTE Elastomeric sealants — silicone and modified silicone — provide elastic joint movement capacity and are commonly used at joint systems and at penetrations not requiring intumescent response. (8.1.6)

8.2 Mortars and Mineral Wool

Primary Firestop Methodradio
Sealant only (small annular spaces)
Mineral wool packing with sealant cap
Cementitious mortar
Intumescent collar (around non-metallic pipe)
Intumescent wrap strip (around non-metallic pipe)
Composite firestop sheet (for cable trays and bus duct)
Firestop pillows (for cable trays and modifiable openings)
Putty pad (for electrical boxes)
Per drawings
NOTE Cementitious firestop mortars are mixed and applied as a wet pour or trowelable mass into large openings — typically over 6 inches in least dimension — and cure to a hard fire-resistive plug. (8.2.1)
8.2.2 Mortars are economical for large openings and openings with multiple penetrants but cannot accommodate joint movement and shall not be used at joints or at penetrations of joints subject to building movement.
8.2.3 Mineral wool is used as a packing material to support sealant or to act as a primary fire barrier in some listed systems; the mineral wool density and packing depth shall match the listed system precisely, because compressed or loose-packed mineral wool will not provide the tested performance.

8.3 Collars, Wrap Strips, and Sleeves for Non-Metallic Pipe

8.3.1 Non-metallic pipe penetrations require an intumescent device that activates when the pipe begins to soften and burn.
NOTE An external collar is a steel band lined with intumescent material and clamped around the pipe at the exterior face of the assembly; as the pipe softens, the intumescent expands inward through the opening, crushing the pipe and closing the void. (8.3.2)
8.3.3 Wrap strips are intumescent strips installed inside the opening, in direct contact with the pipe, and require an outer cap of sealant or a closure detail to retain the wrap strip in the opening.
8.3.4 The choice between collar and wrap strip is governed by the listed system for the specific pipe material, pipe size, assembly type, and rating.

8.4 Cable Penetration Systems

Modifiability of Firestop Systemradio
Permanent (sealant, mortar) — re-firestop required for any modification
Re-enterable (pillows, modular blocks) — designed for cable adds and changes
Per drawings
8.4.1 Single cables, grouped cables, cable bundles, and cable trays each require distinct firestop systems.
NOTE The percentage fill of the opening by cables and the cable jacket type both determine which listed system applies. (8.4.2)
NOTE Composite firestop sheets — laminated mineral wool with intumescent or elastomeric coating — are commonly used over openings with cable trays passing through, because the sheets can be cut to fit around the tray and the cables and replaced when the cable configuration is modified. (8.4.3)
8.4.4 Firestop pillows are bagged intumescent or composite material that can be hand-packed into an opening and removed for modifications, and shall be installed only in listed pillow systems with the specified pillow density, packing pattern, and retention.

8.5 Electrical Box Putty Pads

Putty Pads Required at Rated-Wall Electrical Boxesradio
Yes — at all boxes in rated walls
Yes — where required by IBC 714 (oversized or opposed boxes)
No — boxes do not require protection per IBC limits
Per drawings
NOTE Putty pads are intumescent or elastomeric pads applied to the exterior of electrical outlet boxes installed in fire-resistance-rated walls. (8.5.1)
NOTE Putty pads restore the fire and sound rating that is compromised by the cavity created by the box, and they prevent fire propagation from one box to the back-to-back box in an adjacent stud bay. (8.5.2)
8.5.3 Where electrical boxes are installed in fire-rated walls and meet the criteria of IBC 714 (membrane penetrations exceeding 16 square inches in aggregate per 100 square feet of wall area, or directly opposed boxes in the same stud bay), boxes shall be protected with listed putty pads or installed in a listed enclosure.
NOTE Putty pads also serve the acoustic function described in Gypsum Board Assemblies for back-to-back box conditions. (8.5.4)

9 Joint Firestop Systems

9.1 Head-of-Wall Joints

NOTE The head-of-wall joint is the linear gap between the top of a rated wall and the underside of the floor or roof deck above. (9.1.1)
Head-of-Wall Joint Width (Nominal)range
in
0.54
Default: 1 in
Head-of-Wall Deflection Capacity Requiredrange
in
0.252
Default: 0.75 in
9.1.2 Where the wall is built with a deflection head to accommodate structural movement, the joint shall accommodate the design deflection while maintaining the fire rating and, in the case of smoke barriers, the smoke seal.
9.1.3 Head-of-wall systems are tested under UL 2079 / ASTM E1966 at a defined joint width and movement class; the installed condition shall be within the tested width and movement range.
9.1.4 The joint shall be filled per the listed system, which typically includes a backer of mineral wool or backer rod compressed to a defined density, an intumescent or elastomeric sealant cap on the fire-exposed side, and, in two-sided installations, a similar cap on the opposite side.
9.1.5 The Contractor shall not substitute conventional joint sealants or expanding foams for the listed firestop sealant.
NOTE Expanding polyurethane foam in particular is not a firestop material and has no fire rating regardless of any "fire-resistant" or "fire-block" labeling on the package unless the specific product carries a UL 2079 listing. (9.1.6)

9.2 Bottom-of-Wall Joints

9.2.1 Bottom-of-wall joints — the gap between the bottom track of a rated wall and the floor slab — are also subject to UL 2079 testing in some configurations and shall be sealed with a listed system.
9.2.2 In most rated wall constructions the bottom track is set in continuous contact with the floor and a bead of listed sealant is applied along both sides of the track, but where a bottom-of-wall gap is required by the wall design (for example, to accommodate slab movement at a slab-on-grade joint), a tested joint system shall be provided.

9.3 Wall-to-Wall Joints (Building Expansion Joints)

9.3.1 Linear joints between adjacent wall constructions — typically at building expansion joints or at seismic joints — shall use fire-resistive joint systems that accommodate the design movement and maintain the fire rating.
9.3.2 These systems typically use multiple layers of mineral wool with intumescent or elastomeric sealants, and the listed movement class shall match or exceed the calculated joint movement.

9.4 Floor-to-Floor Joints (Perimeter Fire Barriers)

NOTE The gap between the edge of a fire-resistance-rated floor and an exterior curtain wall is the "perimeter fire barrier" or "safing slot" condition. (9.4.1)
Perimeter Fire Barrier System (Curtain Wall Edge)radio
Required — tested per ASTM E2307 and UL 2079
Not applicable — no curtain wall edge condition
Per drawings
9.4.2 The perimeter fire barrier shall be filled with a tested system that prevents fire and smoke from spreading vertically through the gap from one floor to the next.
NOTE Perimeter fire barriers are tested under ASTM E2307 (intermediate-scale multi-story test) in addition to UL 2079. (9.4.3)
NOTE The system typically consists of mineral wool of a defined thickness and density compressed into the slot, with intumescent sealant caps on the top and underside as required. (9.4.4)

9.5 Floor-to-Wall Joints

9.5.1 The joint between the edge of a rated floor and an adjacent rated or non-rated wall is also subject to joint firestop requirements where the joint represents an interruption of a fire-rated or smoke-rated barrier.
NOTE Tested floor-to-wall joint systems are available for common conditions. (9.5.2)

10 Identification of Installed Firestop Systems

10.1 Labeling Requirements

Identification Label Typeradio
Pre-printed adhesive label from firestop manufacturer
Stenciled identification on adjacent surface
Engraved metal tag
Per drawings
Information Required on Labelcheckbox
Installer name or company
Date of installation
Listed system number (UL or equivalent)
F rating
T rating
L rating (where applicable)
Manufacturer name
Product designation
10.1.1 Every installed firestop system shall be identified with a permanent label affixed to or immediately adjacent to the installation.
10.1.2 The label shall be visible after the system is installed and shall identify the system to inspectors, future trades, and building owners.
10.1.3 The label shall include, at minimum: the manufacturer's name, the date of installation, the installer's name or company, the listed system identification (UL or other agency system number), the F rating and T rating, and the L rating where applicable.
10.1.4 Labels may be pre-printed adhesive labels supplied by the firestop manufacturer or installer-applied stencils on the adjacent surface.
10.1.5 The labeling material shall be durable and resistant to the environment in which it is installed; labels in mechanical rooms, parking garages, and other harsh environments shall be metal or otherwise environmentally rated.

10.2 Concealed Installations

10.2.1 Firestop systems installed in concealed locations — above hard ceilings, within shaft walls accessed only by removable panels, within plenums — shall be identified with a label that remains accessible from the nearest access point.
10.2.2 Where access to the installation is by ladder or by removal of a ceiling panel, the label shall be located so that an inspector working from that access point can read it without disturbing finishes.

11 Field Inspection

11.1 Inspection by ASTM E2174 and ASTM E2393

11.1.1 Where third-party special inspection is required, inspection of through-penetrations shall be conducted in accordance with ASTM E2174 and inspection of joints in accordance with ASTM E2393.
NOTE Both standards require visual inspection of installed work prior to concealment and a percentage of destructive sampling that opens up installed systems to verify packing depth, material composition, and continuity. (11.1.2)
11.1.3 The inspector shall document each inspection with the location, date, system number, observation, and any deficiencies, and shall reinstate the destructively inspected systems to match the original installation.
11.1.4 The Contractor shall coordinate with the special inspector to schedule inspections before any installation is concealed by finishes, fireproofing, or adjacent construction.
11.1.5 Concealed installations shall not be uncovered for retroactive inspection; the inspector's access to the work is the Contractor's responsibility, not the inspector's.

11.2 Inspection Sampling Rates

ASTM E2174 Inspection Programradio
Program A — 2% destructive sample, minimum 1 per floor per system type
Program B — 10% destructive sample, maximum 50 per floor
Not required (no special inspection)
NOTE ASTM E2174 prescribes destructive inspection of either 2% of each penetration system type with a minimum of one per floor per system type, or 10% of penetrations with a maximum of 50 per floor, depending on the program selected. (11.2.1)
NOTE ASTM E2393 prescribes inspection rates for joints that vary by the joint length and the project. (11.2.2)
11.2.3 The Contractor shall confirm the rate adopted by the special inspector and account for it in the schedule and in the work, including the additional installation labor required to reinstate destructively sampled systems.

11.3 Visual Inspection of All Accessible Installations

11.3.1 In addition to destructive sampling, all accessible installations shall be visually inspected for correct labeling, correct location, complete sealant coverage, presence of voids or unfilled gaps, and consistency with the listed system.
11.3.2 Visual deficiencies shall be repaired before the work is concealed.

12 Installation

12.1 Coordination With Penetrating Trades

12.1.1 The Contractor shall coordinate the work of the firestop subcontractor with the work of all penetrating trades.
12.1.2 Openings shall be sized and located by the penetrating trade in conformance with the listed system requirements.
12.1.3 Where a penetrating trade modifies an existing penetration — adds a cable to a cable bundle, replaces a pipe with a different material or size, adds insulation — the firestop subcontractor shall be notified and shall re-firestop the modified opening to a listed system that matches the new condition.
12.1.4 Modifications shall not be made by penetrating trades cutting through or otherwise disturbing existing firestop installations without re-firestop being performed.

12.2 Sequence of Installation

NOTE Firestop installation generally proceeds in the following sequence at each location: (12.2.1)
  • First, the opening is inspected to confirm that it conforms to the dimensions, annular space, and substrate conditions required by the selected listed system
  • Second, packing materials — mineral wool of the specified density, forming rod, or other backers — are installed to the depth and density required
  • Third, intumescent collars, wrap strips, or other devices for non-metallic penetrants are positioned per the listed system
  • Fourth, sealant or sealant equivalent is applied over the packing or wrap, tooled to the surface profile required, and finished
  • Fifth, the identification label is applied
  • Sixth, the installation is documented in the as-installed system schedule

12.3 Mineral Wool Packing

Mineral Wool Densityselect
4.0 pcf
6.0 pcf
8.0 pcf
Per listed system
Per drawings
12.3.1 Mineral wool used as packing shall be of the density (typically 4.0 to 8.0 pounds per cubic foot for firestop applications), thickness, and orientation specified by the listed system.
12.3.2 Mineral wool shall be cut to fit the opening with light interference, packed to the listed depth, and compressed to the listed density.
NOTE Loose-packed or over-compressed wool will not perform as tested. (12.3.3)
12.3.4 The Contractor shall verify the wool density by the manufacturer's published unit weight, not by visual estimation.

12.4 Sealant Application

12.4.1 Sealant shall be applied with a caulking gun or pump fitted with a nozzle sized for the joint width, in a single continuous bead without skips, in conformance with the listed system depth and surface profile.
12.4.2 The sealant shall be tooled to a concave or flush surface depending on the system requirement, with full bond to both substrates and to any packing material below.
12.4.3 Where two-sided sealant is required, the second side shall be applied after the packing has been installed from the first side; sealant applied through the packing from one side does not match a two-sided tested system.
12.4.4 Sealant beads shall not be applied over uncured or partially cured surfaces of incompatible sealant.
NOTE Silicone sealants typically cannot bond to acrylic or polyurethane sealants, and acrylic sealants will not cure properly in contact with uncured silicone. (12.4.5)
12.4.6 Where a substrate has been previously sealed and the new firestop work must adjoin or overlap the prior work, the prior sealant shall be identified and the new sealant shall be confirmed compatible by the manufacturer.

12.5 Concrete and Masonry Substrates

12.5.1 Firestop sealant applied to concrete or masonry substrates shall be applied to clean, dry, sound substrates with the surface laitance, dust, and loose material removed by mechanical cleaning or wire brushing.
NOTE Sealants applied to concrete substrates that are still curing may not bond and may be displaced by the moisture and alkali release from the concrete. (12.5.2)
12.5.3 Where a primer is specified by the listed system, it shall be applied and allowed to dry before sealant application.

12.6 Gypsum Board Substrates

12.6.1 Firestop sealant applied to gypsum board substrates shall be applied to the paper face of the gypsum board with a continuous bead in full contact with the paper.
12.6.2 The paper face shall be intact; torn, abraded, or damaged paper does not provide a competent bonding surface.
12.6.3 Cuts in the gypsum board at penetrations shall be made cleanly so that the firestop material has continuous contact with sound board edges.
12.6.4 Jagged or oversized cuts shall be repaired with gypsum board, joint compound, or with additional firestop material as the listed system permits.

13 Re-Firestopping and Modifications

13.1 Modifications to Existing Firestop Systems

13.1.1 Future modifications to existing firestop systems — adding a new cable to a cable tray penetration, adding a new pipe to a penetration cluster, replacing a damaged penetrant — shall be performed by re-firestopping the modified opening to a listed system that matches the new condition.
13.1.2 The original installation shall be cut back as required by the new listed system, the modification shall be made, and the firestop shall be reinstated.
13.1.3 The Contractor shall provide the Owner with manufacturer's instructions for modification of each system type installed.
13.1.4 The Contractor shall include in the closeout submittals a maintenance instruction document that identifies, for each system installed on the project, the procedures for adding penetrants, removing penetrants, and patching damage.
NOTE This documentation supports the building owner's ongoing maintenance obligations under the International Fire Code. (13.1.5)

13.2 Damage During Subsequent Construction

13.2.1 Firestop systems damaged by subsequent construction — gouged by trades pulling cable, cut through by a contractor making a new penetration without coordination, or otherwise disturbed — shall be repaired to the original listed system by a qualified firestop installer.
13.2.2 The Contractor responsible for the damage shall coordinate the repair and bear the cost; repairs shall not be made by untrained labor or by the trade that caused the damage unless they are qualified per the installer-qualification requirements of this standard.

14 Delivery, Storage, and Handling

14.1 Delivery

14.1.1 Firestop products shall be delivered to the project in the manufacturer's original packaging with all labels, lot numbers, and manufacturing dates visible.
14.1.2 Products with expired shelf life as marked by the manufacturer shall not be installed.
14.1.3 The Contractor shall maintain a delivery log showing the lot number and date of every product container received.

14.2 Storage

14.2.1 Firestop materials shall be stored in their original packaging in a clean, dry, temperature-controlled environment per the manufacturer's published requirements.
14.2.2 Most water-based products are damaged by freezing and shall be protected from freezing throughout transport, storage, and the early cure period after installation.
14.2.3 Solvent-based and silicone-based products generally tolerate freezing but shall not be installed below the manufacturer's minimum application temperature.

14.3 Handling

14.3.1 Containers of firestop sealant, mortar, and intumescent products shall be handled to prevent damage to the packaging and contamination of the contents.
14.3.2 Partially used containers shall be tightly resealed for storage.
14.3.3 Mortar and water-activated products that have begun to set shall not be re-tempered with water.

15 Warranty

15.1 Manufacturer's Warranty

15.1.1 Firestop products shall be warranted by the manufacturer against defects in materials and against failure to perform as tested for the period stated in the manufacturer's published warranty, which is typically a minimum of one year and may extend to the design life of the building for certain products.
15.1.2 The warranty shall remain in effect provided the products are installed in conformance with the listed system, are not subjected to conditions beyond their tested range, and are not modified by others.

15.2 Installer's Warranty

Installation Warranty Periodselect
1 year from substantial completion
2 years from substantial completion
15.2.1 The Contractor shall warrant the firestop installation against defects in workmanship for the project warranty period.
NOTE Workmanship defects include, but are not limited to, deviation from the listed system; insufficient sealant depth, density, or coverage; missing or incorrect packing; missing identification labels; and installation conditions outside the listed system parameters. (15.2.2)
15.2.3 The Contractor shall correct workmanship defects at no cost to the Owner during the warranty period and shall coordinate any necessary product replacement with the firestop manufacturer.

15.3 Conditions Voiding Warranty

15.3.1 Both the manufacturer's and the installer's warranty are voided by subsequent modifications made by others without re-firestop installation, by exposure to conditions beyond the tested range (chemical contamination, sustained temperature outside the service range, water exposure beyond the tested W rating), and by damage caused by other trades.
15.3.2 The Contractor shall document any conditions observed during installation that may affect the performance or durability of installed firestop systems and shall bring them to the Architect's attention before completing the work.

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