TinnerFlow™3rd YearSpecialty DuctRED · Stop / Verify
Per the International Mechanical Code (IMC Section 506), a standard, uninsulated Type 1 commercial kitchen grease duct must maintain a strict minimum of 18 inches of clearance to any combustible materials (like wood framing or drywall).
Per the International Mechanical Code (IMC Section 506), a standard, uninsulated Type 1 commercial kitchen grease duct must maintain a strict minimum of 18 inches of clearance to any combustible materials (like wood framing or drywall).
The Fix: This clearance can only be reduced if you wrap the duct in an ICC-ES listed field-applied multi-layer fire barrier blanket system (like 3M Fire Barrier or FireMaster wrap).
Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.