IBC 717.5
Dampers in walls rated only for structure (IBC 717.5)
Some walls are fire-resistance rated only because the construction type requires it, for example bearing walls. If the wall has no other role, Section 717.5 does not list it, so it needs no damper. The penetration still has to keep the wall’s rating.
What counts as a wall rated only for structure: A rated wall that is not a fire wall, fire barrier, shaft, fire partition, smoke barrier or exterior wall, for example a bearing wall rated only because of the construction type.
Rules last reviewed October 12, 2026. How the rules are checked
Check your case in the tool (2024 IBC)Start the tool with the 2021 IBC · Start the tool with the 2018 IBC
When each damper is required
Every result the tool can give for a duct carrying heating, cooling or ventilation air, or an air transfer opening, through this assembly. Labels show where a result applies only to ducts, only to air transfer openings, or only in some editions.
Also required
- Clothes dryer exhaust ducts through the wall must be galvanized steel or aluminum of the IMC 603.4 thickness, the wall must keep its rating, and the duct may not have fire or combination dampers (IMC 504.2).
- Firestop the penetration so the wall keeps its rating (through-penetration protection). IBC 717.1.2, IBC 714.3 to 714.4.3
- Flexible ducts and flexible air connectors may not pass through any fire-resistance-rated assembly, and flexible air connectors may not go through any wall, floor or ceiling at all. (ducts only) IBC 717.7
Common situations by edition
| Situation | 2024 IBC | 2021 IBC | 2018 IBC |
|---|---|---|---|
| Duct through a bearing wall rated only because of the construction type | No damper required | No damper required | No damper required |
| Air transfer opening through the same wall | No damper required | No damper required | No damper required |
| Clothes dryer exhaust through the same wall | No damper required | No damper required | No damper required |
Select a result to open it in the tool with every answer filled in, including the conditions not listed here.
Exceptions and conditions the tool checks
The tool asks no further questions for a duct through this assembly.
Questions
Does a rated bearing wall need a fire damper?
No, as long as the wall has no other role.
No damper requiredAll three editions
Dampers are required only in the assemblies listed in IBC 717.5 and 717.6. A wall rated only for structural reasons (construction type) is not a fire barrier or fire partition, so it does not need dampers. Confirm with the life safety plan that the wall has no other role. IBC 717.5
Also: Firestop the penetration so the wall keeps its rating (through-penetration protection). IBC 717.1.2, IBC 714.3 to 714.4.3
How do I know the wall has no other role?
Check the life safety plan. If the wall is also a fire barrier, fire partition, smoke barrier, shaft enclosure or rated exterior wall, the rules for that assembly apply.