Duct Insulation 2

[canadeng]

New to HVAC field and I am wondering if anyone knows where you can get some general information on the type insulation to use on ductwork, i.e. when to use accoustic insulation, flexible versus rigid insulation, insulation on outdoor ductwork versus indoor ductwork, etc.
The master spec. that we use has some contradicting information on the type of insulation to use and where it is to be used. Any information would be helpful.
Thanks.

 

[Drazen]

There is no simple rule of thumb, there are many conditions to take care of - fire safety requests, temperature regime (heating/cooling), installation place (indoor/outdoor); acoustics is related to acoustics calculation etc.

if you state what exactly looks contradictory to you, some specific answer might be possible.

 

[MechEngNCPE]

Typically I use f'glass wrap foil-faced insulation on concealed ductwork inside the building. In mechanical rooms and wherever exposed I use board insulation. Outside I use board insulation with aluminum jacket

 

[willard3]

Find anb Engineer where you work to help you with this. It is not a simple problem with a simple answer.

 

[walkes]

ASHRAE 90.1 and the Model National Energy Code for Buildings (Canada) give guidelines on thicknesses. TIAC (Thermal Insulation Association of Canada) has a guidebook available online that may be handy.

http://www.tiac.ca/en/specifications/download.shtml

 

[canadeng]

willard3, I agree with you , however its frustrating when you get 3 completely different answers from 3 different senior engineers.

 

[IRstuff]

"get 3 completely different answers from 3 different senior engineers"

Then, perhaps, it's a don't care, assuming these guys don't ignore negative feedback

TTFN
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