Question by Bradley Foster posted 02 Sep 2005
| Warehouse Area Plenum|
|I am in a situation where when I quoted a project the warehouse area did not have any HVAC which would not require Plenum cable. The company has decided to install several roof top AC units where air return is pulled in from the warehouse ceiling. It is about 100,000 sq feet. Does this create a "Plenum Rated" warehouse?|
Answer by Joseph Golan posted 03 Sep 2005
Typically a warehouse does not have a drop ceiling which would create a "return air plenum" space.
If this area does NOT have a ceiling and they are just pulling the air from from the top of the warehouse then I do not believe that this would be considered a plenum.
If there is a drop ceiling in the warehouse and the space above the ceiling is being used as a return plenum then I would consider this to require plenum rated cable and from your story you would be entitled to an extra.
As always, the final say on the code is from the AHJ (Authority Having Jurisdiction), if you still have a doubt, I would put a call into the code official or inspector.
Joseph Golan, RCDD
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