Exterior Duct Insulation Code Question.
Posted: Thu Jul 13, 2017 10:48 am
Code Reference
IMC 2012
IBC 2012
Code Edition
2012
Code Section
IMC Section 604, IBC 2603
Questions
Roofing, Siding, Wall insulation, even many interiors per the IBC allow a CLASS A Flame and Smoke Developed index of 25/450.
My question is, is there a flame and smoke developed index that applies strictly to outdoor hvac ductwork. In the IMC 2012 there is a section relating to duct insulation, however i feel it applies to indoor duct as the flame and smoke index are 25/50 which is a plenum rating.
If i have an outdoor ductwork system that is covered with insulation, not lined, and then a cladding as a weather barrier is applied. what are the flame and smoke developed index requirements for this insulation application / design? And also what are the flame and smoke developed index requirements of the outdoor weather barrier "cladding". I feel like it should follow everything else that is on the roof / siding / roof insulation / etc. and the Class A should be fine flame spread <25, smoke <450. I just cant seem to find a section that related to outdoor products specifically and why the Class A wouldn't qualify as it is outdoor with everything else that is Class A. Any help is much appreciated. Thank you.
IMC 2012
IBC 2012
Code Edition
2012
Code Section
IMC Section 604, IBC 2603
Questions
Roofing, Siding, Wall insulation, even many interiors per the IBC allow a CLASS A Flame and Smoke Developed index of 25/450.
My question is, is there a flame and smoke developed index that applies strictly to outdoor hvac ductwork. In the IMC 2012 there is a section relating to duct insulation, however i feel it applies to indoor duct as the flame and smoke index are 25/50 which is a plenum rating.
If i have an outdoor ductwork system that is covered with insulation, not lined, and then a cladding as a weather barrier is applied. what are the flame and smoke developed index requirements for this insulation application / design? And also what are the flame and smoke developed index requirements of the outdoor weather barrier "cladding". I feel like it should follow everything else that is on the roof / siding / roof insulation / etc. and the Class A should be fine flame spread <25, smoke <450. I just cant seem to find a section that related to outdoor products specifically and why the Class A wouldn't qualify as it is outdoor with everything else that is Class A. Any help is much appreciated. Thank you.