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Discussion Starter · #1 ·
If you were running wire to a shed some 40 feet from the house would you choose to use wire for direct burial or run it in conduit?

I think both will be about the same difficulty, using a pick & mattock it's just as easy for me to make a deep narrow trench for direct burial or use the other side for a trench for conduit so wondering what others would pick (and why). Thanks!
 

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UAW SKILLED TRADES
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Direct burial is inherently failure prone or damage prone over time. It also requires a deeper trench (24") vs (18") for pvc. IMO pvc with individual thwn conductors is the better of options. Are you running a feeder to a sub-panel or branch circuit of 15 or 20 amps to the shed? If a branch circuit with max protection of 20 amps and gfci protected at it's beginning only 12" deep is required regarless of method.
 

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danandbevsfarm

Personally, Piedmont, for that short a run, I always prefer conduit, It doesn't add a tremendous amount more to the project but adds a whole lot more security that your power line will not leak due to a curious gopher, mole, or even a rock impingement. You didn't say what size wire you were running but if you use conduit allow air space around the NM wiring. Example: 12/2 w/g in at least 1 inch conduit or 10/3 w/g in 1 1/4" or bigger. Dan
 

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Personally, Piedmont, for that short a run, I always prefer conduit, It doesn't add a tremendous amount more to the project but adds a whole lot more security that your power line will not leak due to a curious gopher, mole, or even a rock impingement. You didn't say what size wire you were running but if you use conduit allow air space around the NM wiring. Example: 12/2 w/g in at least 1 inch conduit or 10/3 w/g in 1 1/4" or bigger. Dan

You CANNOT run NM wiring in conduit underground!! It is not rated for wet locations.
 

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Personally, Piedmont, for that short a run, I always prefer conduit, It doesn't add a tremendous amount more to the project but adds a whole lot more security that your power line will not leak due to a curious gopher, mole, or even a rock impingement. You didn't say what size wire you were running but if you use conduit allow air space around the NM wiring. Example: 12/2 w/g in at least 1 inch conduit or 10/3 w/g in 1 1/4" or bigger. Dan
OOPS! You cannot use NM wiring in buried conduit, it must be THWN individual conductors or UF (but why bother with UF).

I would opt for PVC conduit and THWN conductors. That will give you many more options in the future and better protect the wiring.
 

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Discussion Starter · #6 · (Edited)
Thanks all, sounds like conduit is the way to go!

I haven't figured out yet what size wire I need, I'm teetering on a subpanel or not since my current panel is pretty full.

When all said & done I will need 120 ft of wire from the breaker to the shed (with 40 ft under ground) and want it to supply a double-spotlight on the shed, a light inside the shed, and an outlet inside and outside the shed and be able to power an electric lawnmower with a 100 ft extension cord. I'm thinking a 20A breaker will do it, and conduit. What size wire do I need for 120 ft run (plus 100 ft of extension cord for my lawnmower)?
 

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For all my DIY projects, I always use conduit.

Mainly for the added protection/security of the line being damaged.
 

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It's only a shed. Just bury some UF cable 12 inches down on a 20 amp GFCI breaker and call it a day. The wire size will depend upon the current requirements of an electric lawnmower. What kind of current does an electric mower take?
 

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Discussion Starter · #10 ·
It's only a shed. Just bury some UF cable 12 inches down on a 20 amp GFCI breaker and call it a day. The wire size will depend upon the current requirements of an electric lawnmower. What kind of current does an electric mower take?
It draws 12 amps.
 

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It draws 12 amps.
You can see you are already getting close to a 20 amp circuit just with the mower. Are you positive you will not need more power out there down the road?
If it were my shed, it would have a 60 amp sub panel fed with 1" conduit and individual THWN conductors. 4 wires.
Keep in mind you have to dig this trench. Why not cover your bases now. It would be a shame if you realized later on that you did not have enough power out there.
I might even go 1-1/2" conduit just to be sure. This way you could use larger wires if it ever becomes an issue. PVC is cheap, and wire is at a good price right now. Check wire prices at the supply house too.

Have you thought about renting a trencher? I would at least get a price.
 

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I ran a direct burial UF to my garage about a year and a half ago. If I had to do it again, I'd run it in PVC.

A 30" Ditch Witch chain drive trencher was about $140 for 4 hours from a local equipment rental house. That included a trailer, their "damage waiver," and tax. I don't really know if that's a good price or not, but that's what I paid.
 

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Run it in ample sized PVC today - change your mind in the future and then you can just pull bigger wires rather than dig another trench.

I have also found the bottom of the trench is often the hardest to dig, depending on what you are digging through - if 6" not as deep, it's easier to dig.

Then again, if a single 20a circuit is enough for today and expected future needs, I would not go to the extra work and expence.
 

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Most of my time it pretty much sop to run in conduit and be done with it due in the future that person can able upgrade it anytime without digging up again.

Most case If I have to rent a trencher it typically run for about €150 half day but for me I get contractor special so I go full day for that price espcally if you do multi trenchings { it did happend from time to time }

But only major gothca is if you have rocky soil or super hard soil better off rent a small or mini exvactor that useally run about €250 or so depending on the size.

Merci,Marc
 

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I had a Terramite backhoe at the house
Dug a trench for main SE to be buried
Then dug a trench between my shed & the garage foundation
I installed 3 conduits
Just in case I wanted to run a phone line or hard wire a network connection out there
 

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I had a Terramite backhoe at the house
Dug a trench for main SE to be buried
Then dug a trench between my shed & the garage foundation
I installed 3 conduits
Just in case I wanted to run a phone line or hard wire a network connection out there

I hear that Dave. I installed a gazebo last summer and ran only one 3/4" conduit out to it. Now I have to spend over $400.00 to buy wireless speakers. If I would have been thinking. :whistling2:
 

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I ran the feed for my garage in GRC and the low voltage in EMT. Still haven't used the EMT, but it's nice to know it's there. EVERY time I have to fix a garage feed, it is direct burial.
 

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I ran the feed for my garage in GRC and the low voltage in EMT. Still haven't used the EMT, but it's nice to know it's there. EVERY time I have to fix a garage feed, it is direct burial.
You cannot bury EMT. I mean your not supposed to bury EMT. It will be rusted out in no time and non-compliant with NEC rules.
 
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