View Full Version : Romex / pipe
twlofgren
Nov 3, 2006, 11:06 AM
Anybody plus and minus of romex versus pipe for a basement application
bhayne
Nov 3, 2006, 11:14 AM
Romex (through drilled holes in studs and joises) is cheaper and is easily hidden if you intend to finish the basement.
labman
Nov 3, 2006, 11:15 AM
For most residential DIY projects, I would go romex. It is much cheaper and easier. If I went conduit, I would go vinyl or rigid. I see too much thin wall where it has pulled out of the fitting. For some applications, nothing else has the mechanical properties of rigid.
Here is a project where I chose to use rigid. I also replaced the plastic disconnect with a metal one. Everything has held up good for 4 years.
http://www.photolocker.net/images/Labman/KatetheAC.jpg
twlofgren
Nov 3, 2006, 11:50 AM
What an awesome website, thank you guys. I'm glad I sumbled upon it.
omzig
Nov 3, 2006, 11:56 AM
I agree, romex through holes in joists when perpendicular, and stapled to the sides when parallel to the joists. I might add that when coming down a wall exposed, romex must be protected. I think the easiest way to do this is put the romex in a length of EMT with a bushing at the top.
If EMT is installed correctly, including proper support, it won't "pull out of the fittings." I caught my 80 pound nephew doing chin-ups on EMT that is run in my basement and it didn't pull out of its fittings.
ceilingfanrepair
Nov 3, 2006, 12:17 PM
I like EMT when it is exposed/in unfinished areas better because it is much cleaner looking, especially if you require more than three conductors. I forget how many #14s you can have running through one 1/2" EMT, but imagine that many runs of romex on your ceiling. It also makes it easier if you have to change, add, or update wiring. A couple years ago working on a project I learned how to bend EMT and it was very much worth it.
omzig
Nov 3, 2006, 12:30 PM
I tend to agree, but for the average DIY homeowner, it can take a while to get the hang of installing conduit. It's the kind of thing that by the time you're getting good at it, you're done. I remember the first time I tried to bend a box offset, I must have went through 20' of pipe before I got it right. A while back I spent a summer helping an electrician on a major project where I literally ran miles of EMT, and I can now bend a perfect box offset in about 10 seconds with my eyes closed.
BTW, 12-#14 or 9-#12 in 1/2" EMT (THHN). >3 current carrying conductors must be derated though.
tkrussell
Nov 3, 2006, 01:48 PM
I personally don't see any benefit to installing pipe, I assume EMT, in a basement instead of Romex. As mentioned by the previous answers, EMT can be a challenge to learn and install properly, and have it look neat.
Definitely not a job a DIY'er should tackle without plenty of practice.
Like bhanye mentions, Romex will be much easier and less costly to install, plus be ready to finish the basement if desired.
Thou there are fittings made, such as pre-bent box offsets, when done, really can look like a cheesy job, with many added screw connections that can be loose.
Just one correction thou, derating does not need to begin until there are 4 or more current carrying conductors. To expand further, these include all separate neutrals, and does not need to include any shared neutrals on a 120/240 volt single phase circuit, and does not need to include the equipment ground.
I lost count how many basements I have done and none were in any kind of pipe. Only maybe in a workshop or garage, where the flexibility of adding circuits or looks was important.
omzig
Nov 3, 2006, 02:08 PM
Just one correction thou, derating does not need to begin until there are 4 or more current carrying conductors.Not that it really matters, but aren't ">3" and "4 or more" the same thing?
tkrussell
Nov 3, 2006, 02:39 PM
Oops sorry really did not see the greater than sign, reading too fast again.Yes sure is the same thing.
been40
May 12, 2008, 11:44 AM
Derating sounds confusing. I thought I read lot's of posting on this site saying,
You can have 2 romex wires in one stud or joist hole. But reading messages on
This post, tells me that the two romex wires with 2 wire + one ground each,
(assuming connected to different breakers), would carry 2 HOTs and 2 neutral.
That's 4 carrying currents.
To avoid derating, if I understand this correctly, only one romex wire can be going
Through a hole in a stud or joist, IF all the romex wires are going to a separate breaker.
And sounds like the exception is when the neutral is common. <--- what does that
Mean, i.e. common in a sense of being in the main breaker box from the
Same neutral wire coming from the city into the main box, or
Common in a way that, the wires is spliced in switch boxes, which can share a common?
But there is something wrong here. I must a have misunderstood these postings. Since
In our main breaker box, each hole and clips on the main panel, has bundled two romex
Together, each going out from a separate breaker. So are all the neutrals in the main
Considered as common through the house?
stanfortyman
May 12, 2008, 05:26 PM
Bottom line is for cables of #14, #12 or #10, you can have up to FOUR cables before you even have to think about derating, even "3-wire" home runs.
Under NINE CCC's you don't have to worry about derating.