Any disadvantages of Preinsulated AC ducts Vs. GI ducts

[fcu45]

Hi
In my current project, our firm approved Preinsulated AC duct while in the specification it should have been GI duct, the client engineer claims that the Preinsulated duct is not durable (Doesn't last long) and it is cheaper and questioning its efficiency.

So can I get your opinions about that issue?
Thanks

 

[Drazen]

"pre-insulated" can mean lot of things, apparently related to what is insulation material, how it is fabricated.

any kind of generalization is completely unprofessional.

contractor should provide submittal documents and professional engineer knowledgeable in it should approve or disapprove it.

any other way is punishable be law in most of countries i worked in. there are many issues - fire resistance characteristic, possible toxicity, range of application as regards to internal space conditions, life expectancy.

insulation specs likely exists in original project design documents and should be carefully compared to pre-insulated ducts specs. thermal resistance has to be recalculated as well.

you can save lot of money with right decision, sometimes, but you need to know exactly what are you doing.

 

[fcu45]

Hi Drazen thanks for the reply and sorry for shortage of info

The exact name and specification is not with me right now as I left the site I will check it tomorrow, but it is similar to these boards (Approx. 1 inch thick with pinky colour foam)

http://hhbwcl2012.en.made-in-china....ina-Pre-Insulated-Air-Duct-Panel-HHDUCT-.html

http://hhbwcl2012.en.made-in-china.com/product/boVxfeIPXvYK/China-Pur-Air-Duct-Panel.html

Can above info solve the generalization issue?