Fire damper
Closes automatically when heat melts a fusible link, keeping fire from spreading through ductwork in rated walls and floors.
IBC Section 717
Which damper does the code require?
Answer a few questions about the duct and the wall, floor or ceiling it passes through. You get the fire, smoke, corridor or ceiling radiation damper requirement with the code section behind it.
- 2018, 2021 and 2024 International Building Code
- Every exception checked, one damper type at a time
- Printable result with the code sections to cite
Damper types at a glance
Each damper type answers a different hazard. The tool tells you which one the code requires for your penetration.
Smoke damper
Closes on a signal from smoke detection to stop smoke moving through ducts, for example at smoke barriers and rated corridors.
Combination fire/smoke damper
One damper that does both jobs, used where an opening needs both fire and smoke protection, such as most shaft penetrations.
Ceiling radiation damper
Protects duct openings and diffusers in the ceiling of a rated floor/ceiling or roof/ceiling assembly from radiant heat.
Ratings, testing standards and installation basics for each damper type
How the check works
Describe the penetration
Pick the code edition, what passes through (a duct or an air transfer opening) and the assembly it crosses.
Answer only what matters
The tool asks only the questions that can change the answer for that assembly, including every exception in the code.
Get a cited result
See each damper type as required, not required or prohibited, with the reason, the code section and what to specify.
Questions
Which codes does the tool use?
The 2018, 2021 and 2024 International Building Code (Section 717 and the sections it references) and the matching International Mechanical Code sections for exhaust systems. You choose the edition at the start.
Does the result replace the design professional or building official?
No. The tool explains what the model code requires for the situation you describe. Local amendments, project-specific conditions and the authority having jurisdiction can change the answer.
Why can a result say dampers are prohibited?
The mechanical code forbids dampers in clothes dryer exhaust, commercial kitchen grease ducts and hazardous exhaust, because a closed damper would trap lint, grease or hazardous fumes. Those ducts are protected with shafts, enclosures or other methods instead.
What if the wall serves more than one purpose?
A wall can be a fire barrier and a horizontal exit, or a corridor wall and a smoke barrier. Run the tool once for each role and use the most restrictive result.
Is the tool free?
Yes. There is no account, no sign-up and nothing to install. Your answers stay in your browser.