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charleswaz
# of wires in PVC Conduit

I am looking to run atleast 6 #12 wires up through a wall. I would like the ability to run additional lines later on down the road if needed so I am wondering what size PVC conduit I should use? Thanks for any help

NEC
Re: # of wires in PVC Conduit

Depends on how many wires and size You want to add and if too many derating becomes an issue.

3/4" minimum.

Ernie_Fergler
Re: # of wires in PVC Conduit

It basically depends on the type of insulation and size of the conduit.
For example.
If you are using THHN, the most common in these parts, you can pull a count of 15 conductors [#12 AWG] though 3/4" rigid PVC Sched 40/ HDPE conduit, per the 2005 NEC, which I happen to have access to right now.
If you have a specific type of conductor & conduit I will research the exact total allowed.

NEC
Re: # of wires in PVC Conduit
Ernie_Fergler wrote:

It basically depends on the type of insulation and size of the conduit.
For example.
If you are using THHN, the most common in these parts, you can pull a count of 15 conductors [#12 AWG] though 3/4" rigid PVC Sched 40/ HDPE conduit, per the 2005 NEC, which I happen to have access to right now.
If you have a specific type of conductor & conduit I will research the exact total allowed.

All well and good but do not forget about the derating part my friend.

Fencepost
Re: # of wires in PVC Conduit
charleswaz wrote:

I am looking to run atleast 6 #12 wires up through a wall. I would like the ability to run additional lines later on down the road if needed so I am wondering what size PVC conduit I should use? Thanks for any help

Please clarify: do you mean 6 individual #12 wires (THHN) or do you mean 6 "Romex" cables, of size 12/2+ground (usually have a yellow jacket)?

BuilderPete
Re: # of wires in PVC Conduit

charleswaz,

In pvc conduct, a good rule of thumb is usually 3/4" (bigger the better). I would also consider running a second conduit for your future runs(containing no wires)if your budget allows for it.

Some additional helpful tips for installing pvc electrical conduit-

1. Try to align all your joints in the same direction. In other words, make sure that in the direction your pulling your wires try to minimize any internal lips that can hang up your wire or fish line.

2. Use large radius sweeping elbows where you can.

3. Dry fit all your work first before gluing.

4. Use duct tape to cap the ends to avoid any contaminates from entering the conduit.

Hope the tips help you out and good luck!

Pete

_______________________
Measure once, Cut twice

Ernie_Fergler
Re: # of wires in PVC Conduit
Fencepost wrote:

Please clarify: do you mean 6 individual #12 wires (THHN) or do you mean 6 "Romex" cables, of size 12/2+ground (usually have a yellow jacket)?

I too was wondering what exactly the OP was pulling.It just seemed to me like they were referring to spool wire, not Romex.
On occasion we all will pull a run of Romex though PVC for protection.
Without a doubt more info is paramount.:rolleyes:

charleswaz
Re: # of wires in PVC Conduit

Thank you all for the replies. For clarification I am looking to run at least SIX 12/2(with ground) (yellow) romex lines up a straight shot from an unfinished basement through a vertical run with maybe one street elbow at the exit into the unfinished attic. One of the beauties of it being an old house (maybe the only beauty lol) is that the wall cavities are completely hollow so i can put as many conduits as necessary. I just didn't want to run into any issues as far as bundling too many lines together. I hope this makes it a little easier to help with

NEC
Re: # of wires in PVC Conduit
charleswaz wrote:

Thank you all for the replies. For clarification I am looking to run at least SIX 12/2(with ground) (yellow) romex lines up a straight shot from an unfinished basement through a vertical run with maybe one street elbow at the exit into the unfinished attic. One of the beauties of it being an old house (maybe the only beauty lol) is that the wall cavities are completely hollow so i can put as many conduits as necessary. I just didn't want to run into any issues as far as bundling too many lines together. I hope this makes it a little easier to help with

If that is the case then I would forget about conduit and related derating issues. Drill a series of holes and do not bundle more than two cables through a hole.

Re: # of wires in PVC Conduit

The conduit only complicates things, not only wire fill but firestopping. If your house is balloon framed I would skip it.

Ernie_Fergler
Re: # of wires in PVC Conduit
charleswaz wrote:

Thank you all for the replies. For clarification I am looking to run at least SIX 12/2(with ground) (yellow) romex lines up a straight shot from an unfinished basement through a vertical run with maybe one street elbow at the exit into the unfinished attic. One of the beauties of it being an old house (maybe the only beauty lol) is that the wall cavities are completely hollow so i can put as many conduits as necessary. I just didn't want to run into any issues as far as bundling too many lines together. I hope this makes it a little easier to help with

Good luck with the project !!!!

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