IBC Openings and Penetrations
Summary
Openings, penetrations, and joints in rated walls and floors must be protected so the assembly keeps its rating: fire doors and fire windows cover openings, firestop systems cover pipes, cables, and ducts that pass through, and joint systems cover gaps at movement joints and at the building edge. Each protection is a listed, labeled system with its own rating and test method, so the rating on the wall sets what the door, firestop, or joint must be.
Cols
Scope
- Cites the 2024 IBC, Sections 714, 715, and 716. Always verify the adopted code edition and local amendments for the project jurisdiction
- Fire dampers and smoke dampers in ducts and air transfer openings are in Section 717 and the mechanical code, and are not covered here
- Installation and maintenance of fire doors follow NFPA 80, which Section 716 references
- The wall or floor being penetrated is rated under the fire-resistance-rated construction provisions
Terminology
- Opening protective: fire door, fire window, or shutter assembly that closes an opening in a rated wall
- Fire protection rating: hours an opening protective resists a fire test; separate from the wall's fire-resistance rating
- Through penetration: an item such as a pipe, cable, or duct passing completely through a rated assembly
- Membrane penetration: an item that breaks only one face of a rated assembly, such as an electrical box
- Firestop system: tested, listed combination of penetrating item, assembly, and sealing materials
- F rating: hours a firestop system resists flame passage
- T rating: hours a firestop system keeps the temperature rise on the unexposed side under the limit
- L rating: air leakage of a firestop system at smoke barriers
- Fire-resistant joint system: tested system closing a gap at a movement joint, head-of-wall, or floor edge
- Perimeter fire containment: system closing the gap between a floor and an exterior curtain wall
- Positive pressure test: fire door test run with the furnace held at positive pressure over most of the door height (NFPA 252 or UL 10C)
- Smoke and draft control door: fire door tested to UL 1784 that carries an S label
Requirements
Fire doors
- IBC 2024, Section 716.1: openings are protected as required and installed per NFPA 80
- IBC 2024, Table 716.1(2): minimum fire door rating by wall rating
| Wall or barrier type | Wall rating (hours) | Fire door rating (hours) |
|---|---|---|
| Fire walls and fire barriers over 1 hour | 4 | 3 |
| Fire walls and fire barriers over 1 hour | 3 | 3, or two 1-1/2 hour doors on opposite sides |
| Fire walls and fire barriers over 1 hour | 2 | 1-1/2 |
| Fire walls and fire barriers over 1 hour | 1-1/2 | 1-1/2 |
| Fire barriers, shafts and exit enclosures | 1 | 1 |
| Other fire barriers | 1 | 3/4 |
| Fire partitions, corridor walls | 1 | 1/3 (20 minutes) |
| Fire partitions, corridor walls | 1/2 | 1/3 (20 minutes) |
| Other fire partitions | 1 | 3/4 |
| Other fire partitions | 1/2 | 1/3 |
- IBC 2024, Section 716.2.1.1: side-hinged swinging doors are tested to NFPA 252 or UL 10C positive pressure
- IBC 2024, Section 716.2.1.2: sliding and rolling steel doors and shutters are tested to NFPA 252 or UL 10B, with the neutral pressure plane near atmospheric at the top of the door
- IBC 2024, Section 716.2.2.3: doors in stairways, ramps, and exit passageways limit temperature rise on the unexposed side to 450 degrees F (250 degrees C) above ambient at the end of 30 minutes; not required in buildings sprinklered throughout (Section 903.3.1.1 or 903.3.1.2)
- IBC 2024, Section 716.2.2.3.1: fire-protection-rated glazing in doors is limited to 100 sq in.; fire-resistance-rated glazing over 100 sq in. is permitted
- IBC 2024, Section 716.2.2.1: 20-minute doors in corridors and smoke barriers are tested to NFPA 252 or UL 10C without the hose stream test
- IBC 2024, Section 716.2.2.1.1: smoke and draft control doors limit air leakage to 3.0 cfm per sq ft of door opening at 0.10 in. of water, with no louvers
- IBC 2024, Section 716.2.9.3: smoke and draft control doors to UL 1784 carry an S on the label
- IBC 2024, Section 716.2.6.1: fire doors latch and are self- or automatic-closing, with listed exceptions
- IBC 2024, Section 716.2.6.2: single side-hinged doors and both leaves of pairs have an active latch bolt
- IBC 2024, Section 716.2.6.6: a hold-open device closes the door on smoke detector actuation or power loss, with no more than a 10-second delay
Fire windows and glazing
- IBC 2024, Section 716.3: fire windows are tested to NFPA 257 or UL 9 positive pressure
- IBC 2024, Table 716.1(3): 3/4-hour windows in 1-hour atrium, incidental-use, and mixed-occupancy separations, 1-hour fire partitions, and 1-hour smoke barriers; 1-1/2-hour windows in exterior walls rated over 1 hour; not permitted in fire walls and fire barriers rated over 1 hour, or in 1-hour fire barriers, except fire-resistance-rated glazing
- IBC 2024, Section 716.3.2.1.2: fire-protection-rated windows total no more than 25 percent of the common wall area with any room
- IBC 2024, Section 716.2.5.1.2: fire-protection-rated glazing is generally prohibited in fire walls and fire barriers rated over 1 hour; exceptions are horizontal exit vision panels and 1-1/2-hour fire barrier doors, each limited to 100 sq in.
Through penetrations
- IBC 2024, Section 714.4.1.2: in rated walls, the firestop system is tested to ASTM E814 or UL 1479 at a minimum positive pressure differential of 0.01 in. of water, with an F rating not less than the wall's rating
- IBC 2024, Section 714.4.1, exception: steel, ferrous, or copper pipe, tube, or conduit of 6 in. nominal diameter or less through a concrete or masonry wall with an opening of 144 sq in. or less may be sealed with concrete, grout, or mortar
- IBC 2024, Section 714.5.1.2: in horizontal assemblies, the system is tested to ASTM E814 or UL 1479 with an F rating and a T rating each at least 1 hour and at least the rating of the floor
- IBC 2024, Section 714.5.1.2, exceptions: a T rating is not required for penetrations within a wall cavity, certain floor drains, certain 4 in. conduits into switchgear, and steel, ferrous, or copper items up to 6 in. nominal diameter through a single concrete floor
- IBC 2024, Section 714.5.4: smoke barrier penetrations are tested to UL 1479 for air leakage with an L rating at 0.30 in. of water, not over 5.0 cfm per sq ft of opening per system, or 50 cfm per 100 sq ft of wall or floor area
- IBC 2024, Section 714.4.3: a noncombustible item may not connect to a combustible item beyond the firestopping unless the rating is shown to be maintained
Membrane penetrations
- IBC 2024, Section 714.4.2: steel electrical boxes up to 16 sq in. are permitted in walls rated up to 2 hours with limits: 100 sq in. aggregate opening per 100 sq ft of wall area, annular space of 1/8 in. or less, and boxes on opposite sides separated by 24 in. horizontally, or by the cavity depth if the cavity holds cellulose, rockwool, or slag mineral wool insulation
- IBC 2024, Section 714.4.2, exception: non-electrical boxes need an approved membrane firestop system with F and T ratings at least equal to the wall's rating
- IBC 2024, Section 714.5.2: steel electrical boxes up to 16 sq in. are permitted in ceiling membranes of 2-hour assemblies or less, with 100 sq in. aggregate per 100 sq ft of ceiling area and an annular space of 1/8 in. or less
Nonrated assemblies
- IBC 2024, Section 714.6.1: noncombustible penetrating items connecting not more than five stories, with the annular space filled to resist flame and products of combustion
- IBC 2024, Section 714.6.2: penetrating items connecting not more than two stories, with the annular space filled with an approved material
Joints and perimeters
- IBC 2024, Section 715: joints in and between rated assemblies are closed with fire-resistant joint systems tested to ASTM E1966 or UL 2079; head-of-wall and bottom-of-wall joints use the same tests
- IBC 2024, Section 715.4: perimeter fire containment at the floor and exterior wall intersection is tested to ASTM E2307
Worked examples
Door ratings through a floor plate
| Location | Wall type and rating | Door rating |
|---|---|---|
| Corridor wall to office suite | Fire partition, 1 hour | 20 minutes |
| Interior exit stair | Fire barrier, 1 hour | 1 hour |
| Elevator hoistway enclosure | Fire barrier, 2 hours | 1-1/2 hours |
| Fire wall dividing two buildings | Fire wall, 3 hours | 3 hours |
In a building sprinklered throughout, the stair door does not need the 450 degrees F temperature rise limit.
Pipe through a rated floor
A 4 in. plastic drain pipe passes through a 2-hour concrete floor.
| Step | Check | Result |
|---|---|---|
| Penetration type | Through penetration of a horizontal assembly | Section 714.5.1.2 |
| F rating | At least 1 hour and at least the floor rating | 2 hours |
| T rating | At least 1 hour and at least the floor rating | 2 hours, unless an exception applies |
| Test | ASTM E814 or UL 1479 | Listed firestop system for plastic pipe in concrete |
Outlet boxes in a 1-hour partition
| Step | Check | Result |
|---|---|---|
| Box size | Steel, up to 16 sq in. | Allowed |
| Opposite sides | 24 in. horizontal separation | Offset the boxes by at least 24 in. |
| Aggregate | 100 sq in. per 100 sq ft of wall | A 10 ft by 10 ft wall can hold about six 16 sq in. boxes |
Coordination
- Door hardware: hinges, closers, latches, and panic hardware on fire doors must be listed for the door; electrified hardware needs fail-safe release on alarm
- Glazing: specify rated glass by listing; fire-protection-rated glass has area limits, and fire-resistance-rated glass is a wall-like product
- MEP: coordinate penetration schedules early; each pipe size, material, and assembly combination needs a listed firestop system
- Firestop contractor: one listed system per condition, with a drawing or schedule submitted for approval
- Special inspection: firestop and joint systems are inspected by an approved agency; leave the system visible until inspection
- Curtain wall: perimeter containment needs the floor edge detail drawn with the curtain wall system
Common issues
- Unrated hardware: an unlabeled hinge or latch voids the door label
- Louvers and undercuts: smoke and draft control doors and corridor doors may not carry louvers; check undercut limits in NFPA 80
- Gaps at door frames: the frame-to-wall anchorage and caulk must match the listed assembly
- Cable bundles added later: new cabling through an existing firestop requires re-sealing with a listed system
- Wrong wall rating used for the door: the door rating comes from the wall type and rating, not the occupancy
- T rating missed: floors need both F and T ratings unless an exception applies
- Joint systems omitted: head-of-wall and bottom-of-wall gaps in rated partitions are joints, not just caulk
Standards
- NFPA 80: installation and maintenance of fire doors and other opening protectives; referenced by Section 716.1
- NFPA 252 and UL 10C: positive pressure fire tests of door assemblies
- UL 10B: fire tests of door assemblies (neutral pressure)
- NFPA 257 and UL 9: fire tests of window and glass block assemblies
- UL 1784: air leakage tests of door assemblies, for smoke and draft control
- ASTM E814 and UL 1479: fire tests of penetration firestop systems
- ASTM E1966 and UL 2079: fire-resistive joint systems
- ASTM E2307: perimeter fire barrier systems
Sources
- GoCodebook: 2025 California Building Code, Section 714 penetrations (based on the 2024 IBC), https://gocodebook.com/library/us/ca/ca-building-code/chapter-7-fire-and-smoke-protection-features/section-714-penetrations
- GoCodebook: 2025 California Building Code, Section 716 opening protectives, https://gocodebook.com/library/us/ca/ca-building-code/chapter-7-fire-and-smoke-protection-features/section-716-opening-protectives
- UpCodes: 2024 IBC Chapter 7 (Department of Defense adoption), https://up.codes/viewer/department-of-defense/ibc-2024/chapter/7/fire-and-smoke-protection-features