Plumbing in Return Air Ducts

[Gregg Harris]

So then IRC. The PVC pipe can remain. The wires need to be removed and are too close to the edge!

The reason for prohibiting the wiring from being in the plenum run parallel with the duct is the same reason that the pvc piping should not be allowed, it does not meet the ASTME 84 criteria 50 flame spread 25 smoke. The wiring when run the short span of the floor joist is considered to be a minimal amount of PVC exposure to fire where as the pvc piping if it had been conceived to be installed in a paned plenum would not be allowed. The volume of exsposed pvc of the piping is going to be a huge percentage above the wiring.

There needs to be a code change to prevent the piping to match the ASTME 84 standard that applies to material inside of the plenum/duct.

 

[RJJ]

I agree Greg! In this case the IMC would allow based on exception listed above.