The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Parking lot pole light swap....
by gfretwell
10/22/16 09:52 PM
International Wire Colour Codes
by Texas_Ranger
10/22/16 08:24 AM
Son of Sparky
by HotLine1
10/20/16 07:43 PM
Speaking of Plugmold ...
by gfretwell
10/17/16 02:37 PM
Broken battery charger? Check for cobwebs!
by gfretwell
10/17/16 02:30 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 12
renosteinke 6
HotLine1 6
ghost307 5
Potseal 4
Who's Online
2 registered (gfretwell, mbhydro), 251 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#173970 - 01/24/08 07:39 AM Running romex in same joist space as water?
chimo Offline

Registered: 10/13/04
Posts: 14
I'm re-routing some circuits on a residential kitchen project, and was wondering:

Can you place electrical runs in the same wall cavity with plumbing? Good/bad practice? Could this be against code in some areas?

Building Codes & Related References
#173971 - 01/24/08 07:54 AM Re: Running romex in same joist space as water? [Re: chimo]
JValdes Offline

Registered: 06/03/07
Posts: 308
Loc: South Carolina
Yes, but I cannot quote an article to back it up. I know it is done all the time and I would not hesitate to do it myself. Someone else may disagree and provide an article for us. But I think the answer is yes.

#173972 - 01/24/08 07:55 AM Re: Running romex in same joist space as water? [Re: chimo]
renosteinke Offline
Cat Servant

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
I don't see anything against doing so, but experience has suggested a few complications you'll need to address.

Pipes take up space. This can mean there's no room for a box, anchoring the cables can be difficult, and that the cables will need additional protection when the piping pushes them too close to the wall.

#173997 - 01/24/08 06:16 PM Re: Running romex in same joist space as water? [Re: renosteinke]
excellencee Offline
New Member

Registered: 09/07/07
Posts: 5
Loc: PA
I had a HO/plumber who forbid me from running romex in the same stud/joist space as his copper pipes. He claimed electrolisis (sp?) causing pinholes in his copper. He was/is the only plumber that ever identified this as a problem. BTW I run romex in the same bays as plumbing.

#174007 - 01/24/08 07:38 PM Re: Running romex in same joist space as water? [Re: excellencee]
Theelectrikid Offline

Registered: 04/30/04
Posts: 854
Loc: Levittown, PA
Welcome aboard excellencee, from another member from the Commonwealth of PA.

Ian A.
Is there anyone on board who knows how to fly a plane?

#174023 - 01/25/08 09:50 AM Re: Running romex in same joist space as water? [Re: Theelectrikid]
macmikeman Offline

Registered: 07/16/02
Posts: 718
Loc: Honolulu, Hawaii
You can. However, if the spacing is tight, you might want to consider the ambient temperature if you find that your cables are physically touching the hot water pipe. In that case de-rating may be required, depending also on the length of the contact.

#174025 - 01/25/08 10:04 AM Re: Running romex in same joist space as water? [Re: macmikeman]
Zapped Offline

Registered: 10/01/02
Posts: 481
Loc: Huntington Beach, CA, USA
In the same joist/stud bay? Sure. I've worked with so many plumbers I couldn't begin to take a swing at the number, but I've never heard anything about electrolysis or any such thing like that.

Touching? No. Hot water, cold water, doesn't matter. Not a good idea. Vibrations, heat, cold, etc. There are too many variables to even consider doing this. You can get around them without problem. If not, at least use some pipe insulation jacket between your wire and the pipes.

Good Luck!

#174038 - 01/25/08 11:50 AM Re: Running romex in same joist space as water? [Re: Zapped]
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
We do it all the time over here, where hot-water central-heating systems are the most widespread so it's common to have copper pipework running all over the house, not just in the kitchen/bathroom areas.

#174216 - 01/29/08 09:50 AM Re: Running romex in same joist space as water? [Re: pauluk]
mikesh Offline

Registered: 06/07/06
Posts: 614
Loc: Victoria, BC, Canada
Plumber often wrap BX to prevent electrolosis but romex is no problem as it is insulated. excellencee's HO/plumber was thinking bx but he was a plumber and what does a plumber know about electrical installations ;-)

#174223 - 01/29/08 03:03 PM Re: Running romex in same joist space as water? [Re: mikesh]
WireNuts29 Offline

Registered: 07/24/07
Posts: 85
Loc: Mass, U.S.A.
I have first hand experience with a hot water pipe going to the shower, melting into the range feed in my parents house.The house was built in early 70's. this happened probably 6 years ago. The problem most likely started as soon as the house was occupied. But over time the romex jacket and conducter jacket was melted. the only reason for finding the problem was a random shock when getting in the shower, and touching any grounded metal around it. I.e the handle, or drain. I've never seen this problem anywhere else. From then on I always maintain a healthy spacing when running romex anywhere near hot water pipes.

Page 1 of 2 1 2 >

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals