IMC 2024 — Mechanical Ventilation Rates

Updated Mar 25, 2026

Outdoor air rates per ASHRAE 62.1, exhaust requirements, duct construction standards.

Office 5 CFM/person + 0.06/sf. Retail 7.5 + 0.12. Classroom 10 + 0.12. DCV for >500sf/>25 occupants. Kitchen exhaust 100 CFM, bathroom 50 CFM. Parking 0.75 CFM/sf. Ducts per SMACNA.

TAGS

IMC ventilation exhaust ASHRAE-62

DETAILS

code year

2024

code system

IMC

code section

IMC 2024

SOURCES

🔗https://codes.iccsafe.org/content/IMC2021P1

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