Wiring a pole barn--conduit or bare romex?

[james]

Just finished my pole barn and need to wire it. The builder (only does pole barns) said most people just wire it with romex, but he wasn't sure what code is for my county (he's from another state). Any ideas what's required? This is a detched 30x40. I may finish the inside at a later date but am not sure. I have been in a couple commercial pole barns lately, newly built, with just romex.

 

[kbuhagiar]

You really should check with your local authorities - different municipalities have different requirements, especially when it concerns non-metallic sheath wiring.

Good luck!

 

[ownsaglock]

Around here code is if it isnt in a wall/attic its in conduit.

 

[Willy Victor]

I did my 30/36 with conduit even though I could have used Romex. For me it was just easier as I all ready had the pipe and wire.

 

[PAToyota]

Code is that if it is exposed, it has to be in conduit. Bare romex isn't kosher.

 

[markb1]

Mc cable is flexable easy to use but approved for indoors only.
It comes with 2 wires and grd. wire, or 3 wires and grd.wire.
Good for branch circuits (plugs and lights)
http://www.foxelectricsupply.com/content/products/ProductCatalog.asp?qscategoryId=26479

 

[kbs2244]

Romex is for sure faster and cheaper and easier. But in a shop I would be careful to route it along the sides of the posts, not the side facing the room. This would give you some protection from things bumping into it.
The history of conduit goes back to when they started to put electric lights in houses that used to have gas lights. They learned to pull the wires through the old gas pipes so that they didn't tear up the walls as much. From there it got written into some codes. Protection from nails and such.
But Romex is legal in most of the country, and safe if you do it right. The biggest thing is to pay attention to the grounding since it isn't automatic like it is with conduit.
I wowuld get one of those plug in circuit testers that show you if you have done it right or not. And if not, what you did wrong.

 

[Kong]

If it is exposed you "must" have some sort of physical protection. Either metal or plastic conduit or BX cable (armored).

BX isn't always accepted so check your code.

Metal conduit is cheaper overall than plastic (the physical conduit is more expensive but the boxes, etc are cheaper.

BX is pretty expensive unless you don't have any other way to do it or need to do a lot of bends.

Kong

 

[rodnok1]

My undersanding is codes are different between living spaces and non-living spaces. Any wiring such as run across floor joists or between trusses that something can be hung on within so many feet of the ground must be in conduit. you have to keep the wiring away from edge of studs and secured properly near boxes and any transitions. Also any where you could have an impact on the wiring. It's possible in your area you have to run wiring in conduit.

 

[bens]

Just to be safe, anything below 10' went in conduit in my pole barn.

 

[Charles (in GA)]

NEC 2005 Article 334 contains the information on permitted and non-permitted uses of and installation of, NM type cables (Romex)

http://www.nfpa.org/freecodes/free_access_agreement.asp?id=7005SB

Go to page 178.

Charles

 

[jonnysteals]

I know this is an old thread but the link Charles posted is dead now. I am wiring a pole barn and was wondering if I have to use conduit. I would much rather not use it. The building is a pole barn that is mainly used car mataince/storage. No dryway or insoluation are present at this time?

 

[Stuart in MN]

The same advice applies even though it's an old thread...you need to check with your local building inspector to be sure what is allowed in your area.

 

[venom50svt]

how about that pvc or the plastic conduit sold at HD, its pretty cheap and probably easier to work with.
Are we talking if the walls arn't closed up with rock and just stapled to a 2x4?

 

[mtne]

This should have the relevant parts of section 334. paired down to what I think should cover the main questions here.

334.10 Uses Permitted. Type NM, Type NMC, and Type NMS cables shall be permitted to be used in the following:
(1) One- and two-family dwellings and their attached or
detached garages, and their storage buildings.
(3) Cables shall be concealed within walls, floors, or ceilings that provide a thermal barrier of material that has at least a 15-minute finish rating as identified in listings of firerated assemblies.

(A) Type NM. Type NM cable shall be permitted as follows:
(1) For both exposed and concealed work in normally dry
locations except as prohibited in 334.10(3)
(2) To be installed or fished in air voids in masonry block
or tile walls
(B) Type NMC. Type NMC cable shall be permitted as
follows:
(1) For both exposed and concealed work in dry, moist,
damp, or corrosive locations, except as prohibited by
334.10(3)
(2) In outside and inside walls of masonry block or tile
(3) In a shallow chase in masonry, concrete, or adobe protected against nails or screws by a steel plate at least
1.59 mm (1⁄16 in.) thick and covered with plaster, adobe,
or similar finish
(C) Type NMS. Type NMS cable shall be permitted as
follows:
(1) For both exposed and concealed work in normally dry
locations except as prohibited by 334.10(3)
(2) To be installed or fished in air voids in masonry block
or tile walls


334.12 Uses Not Permitted.
(A) Types NM, NMC, and NMS. Types NM, NMC, and
NMS cables shall not be permitted as follows:
(1) In any dwelling or structure not specifically permitted
in 334.10(1), (2), and (3)
(2) Exposed in dropped or suspended ceilings in other
than one- and two-family and multifamily dwellings
(3) As service-entrance cable
(4) In commercial garages having hazardous (classified)
locations as defined in 511.3

(9) Embedded in poured cement, concrete, or aggregate
(10) In hazardous (classified) locations, except where specifically permitted by other articles in this Code.
(B) Types NM and NMS. Types NM and NMS cables
shall not be used under the following conditions or in the
following locations:
(1) Where exposed to corrosive fumes or vapors
(2) Where embedded in masonry, concrete, adobe, fill, or
plaster
(3) In a shallow chase in masonry, concrete, or adobe and
covered with plaster, adobe, or similar finish
(4) In wet or damp locations

334.15 Exposed Work. In exposed work, except as provided in 300.11(A), cable shall be installed as specified in 334.15(A) through (C).
(A) To Follow Surface. Cable shall closely follow the surface
of the building finish or of running boards.
(B) Protection from Physical Damage. Cable shall be
protected from physical damage where necessary by rigid
metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or other approved means. Where passing through a floor, the cable shall be enclosed in rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or other approved means extending at least 150 mm (6 in.) above the floor.
Type NMC cable installed in shallow chases or grooves
in masonry, concrete, or adobe shall be protected in accordance with the requirements in 300.4(F) and covered with plaster, adobe, or similar finish.
(C) In Unfinished Basements and Crawl Spaces. Where
cable is run at angles with joists in unfinished basements
and crawl spaces, it shall be permissible to secure cables
not smaller than two 6 AWG or three 8 AWG conductors
directly to the lower edges of the joists. Smaller cables
shall be run either through bored holes in joists or on running boards. Nonmetallic-sheathed cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing or shall be protected in accordance with 300.4. Conduit or tubing shall be provided with a suitable insulating bushing or adapter at the point the cable enters the raceway. The sheath of the nonmetallic-sheathed cable shall extend through the conduit or tubing and into the outlet or device box not less than 6 mm (1⁄4 in.). The cable shall be secured within 300 mm (12 in.) of the point where the cable enters the conduit or tubing. Metal conduit, tubing, and metal outlet boxes shall be connected to an equipment grounding conductor complying
with the provisions of 250.86 and 250.148.

Clear as mud? I would still check with the local AHJ and see how they categorized a pole barn and what they would like to see installed and how.

 

[jonnysteals]

Yea clear as mud. I believe it is basically up to the local inspector interepration of protected from physical damage. I planned on runnign wy wires on the 2-4 behind the 6x5 posts. The wires would be stapled to either the top or bottom of the 2x4 and not to the face of the 2-4. I could argue this is protected but I can see how it could be argued it isn't as well. Hopefully my inspector will agree that is protected because I spoke with two different electricians and both had different views on this as well.

I spoke with another garage journal board memeber last night and he suggested that I may need to only run the bottom 8 feet or so in conduit and the rest could be regular romex. The theory behind this was it was area that was easy accesible by people at the bottom so protect thw wire. There are many solutions to the problem but it may be better just to call my local inspector and get his views on this and hopefully there is not a problem with romex.

Thanks for all the help.