Electrical – Crossing cold air return ducts with romex

electrical

The house was built in the 50's, and am in Ontario. The house has all copper wiring, but it is older, and has no ground. I am quite competent when it comes to following code, but I have not found a ton of information on the internet about crossing cold air return ducts with wire. I was just hoping to get an electrician's opinion on the best way to do it.

From what I have found in the CEC and internet, you are allowed to cross cold air return ducts as long as you don't run wire along the inside length wise. I am looking to cross the cold air return duct because it spans almost the entire width of the house. These are the kind of ducts where there is just floor joists covered with sheet metal.

Im not looking to use them as a raceway, i just want to run a wire across them so i don't have to go around

I have read one method would be to drill holes on each side of the joist, use EMT conduit to pass the wires through and caulk the outsides to close the duct off to outside air. Back when the house was built, they just drilled holes and ran NM cable across. How would an electrician approach this problem?

Also, this is the way they ran NM cable across the actual air ducts. What do you guys think of this? Seems hackish to me.

Thanks

enter image description here
enter image description here

Best Answer

You are correct. You cannot run NM cable through an air duct. EMT is approved to run through a plenum, but I can't speak to the specific method you described. Someone with more experience may edit this answer.

The way they ran the NM looks fine. Some of the holes they drilled might be a little too close to the bottom of the joist, but no big deal. The wood does look a little messy. Looks like something I would have done to keep my wife from hanging clothes from the cables. So long as the radius of the bends in the cable is not too severe and there is no friction wear, no problem.

Related Topic