[hbuilder]

Is it code compliant to run romexes (NM-B) across a cavity between two studs (2x6) which is to be used for cold air return?
I might have to run 8 romexes through that space!

Alternative is to run the cold air return in another cavity parallel to a copper gas line.

Any advice would be appreciated.

Thank you!

[acetc]

They will need to be in conduit to be run in the return air.

[mydogs]

Section 300.22 B of the National Electrical Code 2005 states that only wiring of type MI or MC shall be permitted in ducts or plenums specifically designed for environmental air. This limits the use of materials that would contribute to smoke and combustion in case of fire.
Romex would not be permitted by the code whether enclosed or not.

[hbuilder]

Would romex through conduit have the same effect as MI or MC?

Another option I am thinking of is to use 1/2" OSB board to build a box to isolate wires to one half depth of the 2x6 and use the other half of 2" (or so) as the cold air cavity.

[mydogs]

It says that you can use rigid metal conduit, or electrical metallic tubing, ck with Lowe's or a hardware or eledtrical supply store, the way I read it is that the wires must be enclosed in a metal conduit that has no "non-mettalic" covering on it. Romex could be used in this application.
An electrical supply store would be the best place to purchase metal conduit, rigid or flexible, and could also advise you as to exactly what the electrical code permits, and the best material to use, and the most economical.
It goes on to read that the purpose of this is for fire safety, and the metal conduits would be non combustible as opposed to a wood enclosure, and also take up less room.
In case of a fire, insurance companies usually ck to make sure work is done according to "code".

[hbuilder]

in case of a fire, insurance companies usually ck to make sure work is done according to "code".

Since my work will be inspected by State board of Electricity, I should be covered in such a situation, right?

[mydogs]

You did not mention whether the job was new construction, your residence, or if you are doing it for someone else. My advice would be to go to an electrical supply store to purchase the material, (conduit), and explain the application to them. They know the code book well. Refer to Article 300.22, sec. B of the National Electric Code, 2005.
They will sell you the right material for your job and it should pass inspection.

[tkrussell]

At the end of Section 300.22, there is the attached exception, stating that Section 300.22 does not apply to stud and joist cavities in a dwelling.

Best to check with your local inspector or code agency to determine if this practice is allowed in your area, and what an acceptable remedy would be if not allowed.

I can tell you, in the new England states,due to this exception, Romex is allowed to pass through a return air duct that consists of covered wood framing members

The last place I find good advice is a clerk in a hardware store, unless that clerk can produce a license or certificate for that trade. And yes there are licensed tradesmen/women working in these stores. One gentleman comes to mind, his poor knowledge and poor workmanship caused his termination from an electrical contractor, and he could only find a job in a hardware store, so buyer beware.

[hbuilder]

you did not mention whether the job was new construction, your residence, or if you are doing it for someone else. my advice would be to go to an electrical supply store to purchase the material, (conduit), and explain the application to them. they know the code book well. refer to Article 300.22, sec. B of the National Electric Code, 2005.
they will sell you the right material for your job and it should pass inspection.

In fact I am finishing my previously unfinished basement. I missed to state the project details!

[hbuilder]

At the end of Section 300.22, there is the attached exception, stating that Section 300.22 does not apply to stud and joist cavities in a dwelling.

Best to check with your local inspector or code agency to determine if this practice is allowed in your area, and what an acceptable remedy would be if not allowed.

I can tell you, in the new England states,due to this exception, Romex is allowed to pass thru a return air duct that consists of covered wood framing members

The last place I find good advice is a clerk in a hardware store, unless that clerk can produce a license or certificate for that trade. And yes there are licensed tradesmen/women working in these stores. One gentleman comes to mind, his poor knowledge and poor workmanship caused his termination from an electrical contractor, and he could only find a job in a hardware store, so buyer beware.

The project had already passed the electrical rough-in and framing inspection. I came across this issue due to a slight modification in the duct work.

Even though the framing inspector said it is OK to run return air through a cavity where there is a gas line running parallel through it (for my main-level fireplace), I do not feel very comfortable doing so. In an event of any leak in that pipe that would be much more disastrous. To me, it is safer to have Romex rather than gas line in a return air cavity!

More than just following the code, I am trying to be safer.

Romex is allowed to pass thru a return air duct that consists of covered wood framing members

There will be 6 Romexes running across the cavity, and I am wondering if that number is too high.

Thanks

[hbuilder]

I talked to my inspector and he said it is OK to run wires across (perpendicular to the stud) a return air cavity in between the studs. Even though not required by code, it is OK to sleeve it with a flexible metal conduit but not copper pipe.

Thanks for all the replies...