# Shop Wiring - Metal or Plastic Conduit



## Marshall1 (Nov 29, 2016)

I am in the process of adding more power to my garage/workshop via a surface mount subpanel. I am planning to run surface mounted 120 and 240 volt outlets, also a 30A 240V electric heater. For ease of installation I wanted to use plastic conduit. Can anyone chime-in on the topic of plastic vs metal conduit? 
Also, I wanted to run a 240v outlet for potential use later. I noticed there is 3-wire and 4-wire 240V outlets. Wanted to know which one I should install?


----------



## Holbs (Nov 4, 2012)

At first, I wanted to just simply reply "Really?" 
But I am in the construction business so maybe I understand electrical wiring more than if I never been around it.
A big "NO" to plastic conduit for electrical wiring. Plastic conduit is more reserved for "low" voltage applications such as audio/video or voice/data or alarm wires.


----------



## Sparks500 (Jun 30, 2017)

I don't know where you're located so I don't know the codes in your area. I always keep an eye on the future, as in will I have to change this to sell the building. I like metal, but, I'm an electrician. To me, plastic is for wet areas or underground use where it's more protected and metal is for everywhere else. Codes in the Chicago area are almost exclusively metal conduit.
Bending conduit is rather easy to learn, but, like I said, it's basically second nature to me.


----------



## becikeja (Sep 12, 2010)

Really depends on local code. Most areas of the country you can simply use romex and skip the conduit altogether as long as its covered by the drywall. If you can use plastic conduit you want to make sure you run a separate ground wire. If you use metal conduit, as long as all connections are tight and conductive you can utilize the conduit as your ground. Again, I can't stress enough to respect your local code. Lets say something does go wrong at some point. If your insurance adjuster determines the circuit was wired non-compliant to local code, you run the risk of a claim not being paid. As mentioned above Chicago mandates metal conduit. My opinion its to protect the local unions which are very strong. In the South they use romex almost exclusively in residential applications, but there are some specific cities with exceptions to this. Bottom line both are safe, but local code dictates the installation. Be cautious, local code can mean state, county and/or city depending on where you live.


----------



## WhyMe (Feb 15, 2014)

PVC conduit is fine for wiring and is approved by the NEC where installed to code requirements. The down side to PVC it needs more support points to prevent sagging on horizontal runs. EMT is harder to install due to the learning curve of making bends unless you use premade bends and couplers. Just check your local code to see what's allowed.


----------



## splintergroup (Jan 20, 2015)

Also consider that EMT has a smaller outside diameter than PVC for a given ID and is way easier to feed wire through.


----------



## alittleoff (Nov 27, 2014)

Why Me is correct unless you have a local code that says no. AlsoIt will look terrible after a little while. No matter how you install it surface mounted it will sag and will not be level. As for the receptacle just pull another wire for the neutral if the 220 receptacle is 4 wire. Most 220 volt circuits such as saws and motors don't require a netural.


> PVC conduit is fine for wiring and is approved by the NEC where installed to code requirements. The down side to PVC it needs more support points to prevent sagging on horizontal runs. EMT is harder to install due to the learning curve of making bends unless you use premade bends and couplers. Just check your local code to see what s allowed.
> 
> - WhyMe


----------



## MrRon (Jul 9, 2009)

If you want to do it right and you are not concerned by a minor increase in cost, use EMT. When confronted by an "OK" way and a "best" way, I will always opt for the best way.


----------



## TheFridge (May 1, 2014)

Unless you plan on running your car into it or using it as an anvil, pvc will be just fine.


----------



## Holbs (Nov 4, 2012)

I guess I stand corrected and admit my error. I thought PVC was a total NONO for inside use of conduit (ok for underground or outside when using outdoor rated electrical cable).


----------



## richardchaos (May 12, 2017)

I used metal conduit and fitting on my last shop for one they look cool. But when I retrofitted a one car garage insulted and drywalls it I just ran it through the walls and used plastic outlets to save money. It was a pain to get the drywall cut and imp lace and get the outlets coming through the drywall at the exact place. BUT heck thats what tons of plaster are for


----------



## TheFridge (May 1, 2014)

No biggie. really you can use it about anywhere. I can't think of any job off hand that you couldn't use it for in a residential setting. Not many in a commercial setting as well.


----------



## John_ (Sep 23, 2013)

I think EMT looks better for inside use and it is smaller in diameter

With that being said - PVCis fairly easy to bend just by heating it up with a heat gun so if you have some unusual situations, keep that in mind


----------



## Marshall1 (Nov 29, 2016)

Thanks all for your comments. I appreciate the responses on my first post. I must say to all, I am grateful for the ability to have information on a variety of topics readily available from a wide range of resources. I guess it is the Thanksgiving Thing. 
I just returned a bag full of plastic conduit fittings as you persuaded my decision to use metal. The comments about it sagging concerned me as well and the comments regarding the local code. In Dayton OH I believe plastic is acceptable but going with metal. Now I get to buy a tubing bender.

As for my 240m volt question, I have always found this odd not to have a natural when running 240v. I will add a spare ground wire just in case I need one for my short 50A 240V run. May need it for a welder connection.

My Delta TS has an option of running on 120 or 240V. Any advantage to me making the switch? My initial thought was that it would limit my placement of the saw. On the upside, I am sure the motor will run better. Anyone have experience with this?


----------



## MrRon (Jul 9, 2009)

Whether 120 or 240, the saw will run the same; no better, no worse.


----------



## WhyMe (Feb 15, 2014)

Actually the motor will run cooler on 240V, less amp draw. Power wise there is no difference, but I do believe running it on 240V vs 120V does help with motor life.


----------



## woodbutcherbynight (Oct 21, 2011)

For the shop outlets consider putting in twin outlets. Not much extra in cost but much easier to have 4 available then running extra cords. On your 220 outlets paint the covers some odd color like bright orange. They stand out as a visual reminder it is 220 volt. Also label the cover how many amps breaker your have to it. My 110 outlets used for tools like miter saw and 12 inch sander I have set up with a series of outlets at 20 amps and used gray outlets and covers. Again a visual yes/no rather than guess later.


----------



## Fresch (Feb 21, 2013)

> Actually the motor will run cooler on 240V, less amp draw. Power wise there is no difference, but I do believe running it on 240V vs 120V does help with motor life.
> 
> - WhyMe


It runs and draws the same amount of watts, 240v = (2) 120v each drawing ? 5amps = same as (1) 120v drawing 10 amps. The motor was made to run at the temp. Produced 1200watts.


----------



## Fresch (Feb 21, 2013)

> For the shop outlets consider putting in twin outlets. Not much extra in cost but much easier to have 4 available then running extra cords. On your 220 outlets paint the covers some odd color like bright orange. They stand out as a visual reminder it is 220 volt. Also label the cover how many amps breaker your have to it. My 110 outlets used for tools like miter saw and 12 inch sander I have set up with a series of outlets at 20 amps and used gray outlets and covers. Again a visual yes/no rather than guess later.
> 
> - woodbutcherbynight


 If you look orange is for isolated ground recepticals, that wire different.


----------



## woodbutcherbynight (Oct 21, 2011)

> If you look orange is for isolated ground recepticals, that wire different.
> 
> - Fresch


 Okay, so orange is not an acceptable color. Thanks for this info. My daughter is thrilled. She wanted to paint those covers purple and add glitter. Said it really would make a fashion statement.

LOL


----------



## YesHaveSome (Sep 10, 2017)

I just added a subpanel to my garage a few weeks ago and ran about 15 outlets (110 and 220) and added 5 8' LED fixtures. I used EMT. The bending was tricky at first but there are a lot of videos on YouTube for help. There is also a good app for the bending calculations called QuickBend.

I used EMT for a couple of reasons 1) some odd runs that would have required a bunch of different fittings with PVC and 2) looks way better and it also slimmer and more streamlined.


----------



## Marshall1 (Nov 29, 2016)

YeshaveSome-Thanks for the comments. Bending will be a learning lesson for me.
WoodbutcherbyNight. For my duplex 20 Amps GFI outlets, I will be doing exactly as mentioned. One will tied to Breaker "A" the other to Breaker "B".


----------



## woodbutcherbynight (Oct 21, 2011)

I have some EMT bending to do myself on a table saw cabinet I am working on currently. Probably overkill to put in the EMT but I don't want to say later, "I knew I should have used EMT."

LOL


----------



## zzzzdoc (Mar 6, 2010)

I like the idea of color coding outlets. Is there a specific color scheme that is used (I see above that orange has a meaning)?


----------



## John Smith_inFL (Dec 15, 2017)

I worked in a warehouse and woodshop for Lockheed-Martin Aerospace
and they were constantly adding new outlets and equipment with rigid EMT conduit.
I asked the guy why they didn't use the gray sched 80 PVC and they said
that Lockheed prohibits any kind of plastic that carries electricity. even if it is 9 volts.

like said above - check with your local code enforcement people for what you can use
in a residential setting. in my area, permits are required for ANY kind of additions/alterations.
I had to get a $113.00 permit to install motion sensor floodlights on the house I just bought.
try to pick up a recent copy of the NEC code book.

and when I think about it - I have only noticed orange electrical covers in hospitals.


----------

