Current Set Up:
1 - Residential setting
2 - Cloth covered 2 conductor "romex" running inside steel conduit to
bathroom ceiling light fixture.
3 - One nut on inside of fixture box, one nut on outside, securing
threaded conduit to the fixture box.
4 - Access to fixture and conduit from above is available through
Replace old light fixture with exhaust fan/light fixture. Single unit,
fan and light controlled by a single switch.
Conduit extends into area where the new fixture will be placed. About
4" of conduit needs to be cut off.
The fan has a plastic box for the wires with 1/2" knockouts for a
romex clamp. Is it OK to cut the conduit back as far as needed and
simply let the cloth covered romex extended freely from the end of the
conduit into the romex clamp or is a junction box required so that the
end of the conduit can be secured?
If a junction box is required, is there a special connector that can
be used since the threads will have been cut off?
BTW...I have not yet seen the current set up, only spoken to my son
about the issue. I should be able to actually see it this weekend.
I've told you everything I know about the situation so far.
On Wednesday, 19 September 2012 16:38:11 UTC-4, DerbyDad03 wrote:
Is the conduit required at all? By some local code? Or is this a multi-unit building?
Outside a few special places that we read about (Chicago? NYC?) romex by itself should be fine within the enclosed walls and ceilings of a single-family residence.
So if it doesn't need to be there at all, I would postulate that it doesn't matter how much of it you cut back, and it doesn't need to be coupled to the new box. Just let the romex emerge from it and run to the new fixture.
If there's some reason it was required to begin with, then scratch that.
Some further comments:
- I'm unclear whether romex within conduit is code-compliant. I had understood that metallic conduit was to contain individual insulated wires ("THHN" or similar). But I've never worked with conduit; I considered it for my garage but went with AC (aka BX), partly because I couldn't find a decent how-to on working with conduit outside commercial properties. So on this I will defer to pretty much anyone who says they know what they're talking about.
- Cloth-covered romex is old. Code may not technically require existing cable to be replaced for a job like this but if the fan/light thing says it requires conductors rated to 90 C, you may not be in compliance in that respect.
- Does that romex have a ground conductor? I'd want a bathroom fixture grounded. They may have been depending on the conduit for ground. In which case, terminating the conduit at a metallic box somewhere nearby and running grounded romex from there to the new fixture may be an option--and that fixes the 90C requirement at the new fixture, too. Of course that box will need to remain "accessible" so you may need to leave it exposed through the attic floor, which may or may not be acceptable. As to how to clamp the conduit at the new box; I thought there were terminations that clamped onto metallic conduit with setscrews. Certainly that's what I see for surface-mounted metallic conduit in commercial buildings.
I don't know exactly what the code says, but last
year I installed my own furnace and had it pass
electrical. The old furnace from 25 years ago used
romex from the panel to the joist above the furnace.
Then the romex was passed through a metal conduit
to the furnace switch box. I did the same and it passed.
I've also seen that done on new furnace installs here
in NJ, which is why I did it. But then the fact they used
romex inside a conduit for a bathroom fixture suggests
that this may be a city or such with different requirements.
The typical small conduit of that size that I've seen doesn't
use threads. It uses a metal fitting that goes into the box,
the conduit slips into the fitting and is secured with a
screw that tightens from the side.
This is a fairly old house in a suburb so I don't know if the conduit is
there because of code or just because the builder/electrician wanted to use
As I noted below, i haven't seen the set up yet. When I asked my son how
the conduit was attached to the box he said there was nut on the inside and
outside of the box. I asked him if the conduit was threaded and he very
quickly answered that it was. When I verified that by asking if the threads
would be cut off when he shortens the conduit he once again answered yes.
I'll know for sure when I see it this weekend.
No, you would have to make a proper transition...
The easiest way to do that which is commonly
used in commercial buildings where armored
cable is joined to conduit to go down a wall cavity
to a switch box or outlet box is to use a normal
EMT fitting, then a Rigid Metal Conduit coupler
to connect to an AC type clamp... The conductors
fed into the conduit and outlet box are those from
the AC which have had the outer metallic protection
removed to the transition point where conduit meets
That fact that some wiring method is not required
where you happen to find it does not mean that
the applicable code dictating its proper use ceases
to apply... It is what is installed so you have to
either work with it properly or remove it...
Is there some reason why the conduit can not
be connected to the new fan fixture ?
On Wed, 19 Sep 2012 13:38:11 -0700 (PDT), DerbyDad03
They make thread less compression fittings for rigid metal conduit.
On 9/19/2012 8:47 PM, email@example.com wrote:
Or, if you can move the conduit to one side or the other of where the
fixture resides. Then, put in a junction box and a short run of
whatever is code for your area, i.e. Romex or BX. And, if the conduit
is all that is providing the safety ground, you might want to tighten up
the nut at the other end .... like in the switch box, or add a green
safety ground wire inside the conduit.
Non-metallic sheathed cable ("Romex") is permitted in conduit in any location
where it is
permitted without conduit -- and there are circumstances under which the NEC
*requires* it to
be in conduit.
The CEC may be different, I don't know -- but I bet not. I doubt that you can
cite any article of the
CEC which prohibits running Romex in conduit, and I'm sure you can't cite that
in the NEC.
I have never seen threaded emt conduit, but have used these to connect
conduit to a box
Cannot comment on whether running romex in conduit is against code or not,
too many differing opinions on the web
The NEC covers low voltage work too but that may be a shock to a lot
Some AHJs are even asking for permits these days since there are not
many actual utility company employees (who are exempt).
Florida licenses low voltage contractors.
*No. The conduit is probably serving as the grounding conductor. You would
need a metal junction box and can use metal flexible conduit to feed the new
fan. Once the junction box is connected properly and tightly to the
conduit, you can also use Romex from there to feed the fan. Just attach the
ground wire to the metal box tightly. If that conduit extends down to the
switch, you may be able (With elbow grease) to pull out the old cloth cable
and pull in some individual conductors. That way you can have two switches,
one for fan, one for light.
*After you cut the pipe, make sure there are no burrs inside or out. A
small round file is useful for deburring the inside. You would use a
compression connector on the end of the pipe. They are available for rigid
and EMT conduit.
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