/ Field knowledge · IMC 311
The vents and the RTUs have to share a roof on purpose.
IMC 311: approved smoke and heat vents are required in the roofs of one-story buildings where the International Fire Code requires them. The IMC does not create the full trigger — it points to the IFC for when and how.
Educational 2024 IMC 311. Confirm adopted fire code. This is not a vent-area design. Mechanical may not own the vents, but RTUs, curbs, intakes, exhaust, PV, and roof access can block them.
- Overlay the roof mechanical plan with the architectural/fire-code vent layout.
- Verify clearances, access, curbs, intakes/exhaust, structural openings, and smoke-control notes.
- Escalate warehouse, storage, high-piled storage, manufacturing, and one-story buildings where the fire-code package may require vents outside the mechanical designer’s normal scope.
Source: DCT 311 · 512: IBC 909 smoke control is a different system · discharge: 501.3.
What to send
Roof plan, occupancy/storage description, and whether a fire-code package already locates vents.
If the RTUs and the vents share a roof
Send the roof plan. Masterbuild will say whether this is a 311 overlay problem or an IFC trigger nobody put on the mechanical set.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
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