How to Wire a Shed for Electricity

Intro: How to Wire a Shed for Electricity

Versión en español

I found myself in need to move my noisy woodworking to my back yard to avoid waking up my lady who works night shift. I decided to wire my shed and after some homework and the help of the Instructables community I started my project. Before we start I assume that you know how to wire the different fixtures.

First you will need:

• Liquid tight conduit or direct burial electrical cable
• Electrical wire (12-2)
• Switch box
• Switches, electrical outlets, light fixtures

STEP 1: The Right Conduit

The right conduit to use is a liquidtight conduit approved for use underground or outside installations. It is a metal conduit covered by resistant plastic. You should find out if there is a code regarding buried electrical lines. My conduit will be buried between 18" and 24". You do not need to worry about frost lines because you are dealing with electricity and not pipes carrying water.
I bought 50 feet of conduit, more than the distance between my house and my shed. The conduit will be connected to a switch box in my basement and to a junction box inside my shed.
You will need an electrician's fish tape to pull the wire inside the conduit. If you find difficult to pull the wire there is a clear lubricant that you can use to make the job easier. Make sure that the lubricant dries before you connect the wire to the main box.

STEP 2: Wire

The wire that I got for this project was a type 12-2. It is the right wire for home wiring and for my needs in my shed. Make sure that the wire is inside the conduit before you start the installation.
I became aware that it is against electrical codes to use sheathed cable inside a conduit. Therefore you need to pull three unsheathed wires inside the conduit with a fish tape.

• Black wire for the "hot" or "live wire"
• White wire for the neutral
• Green or uninsulated wire for ground

STEP 3: Switch Box

The switch should be inside the house for safety reasons. If you need to turn off the electricity that goes to the shed, the wire underground outside the house will not be energized. Also you will be able to turn off the electricity when you leave for vacation.
One end of your conduit will be connected to this box. When all the wiring is safely installed you can wire the switch to your home electrical panel.

STEP 4: Digging the Trench

I dug the trench to bury the conduit by hand ( I mean not literally but with a shovel). I dug for several days, taking my time. If you want to spend some money and rent a trench digger you can but money was an issue for me so this old man decided to dig the trench himself and do it at his pace.
I found a large rock while digging and I did not have any dynamite to blast it so, I patiently dug around it.

STEP 5: Wiring the Shed

After I determined the best location for the junction box, I built a panel where I could keep everything together: the junction box, the electrical outlets and the light switches.
I drilled pocket joints in two pieces of 2 x 4 and screwed them to the supporting studs. Then I screwed a 3/4 inch board on the 2 x 4 's.

STEP 6: Connecting the Circuit to the Switch and the Main Box

I selected one of the basement windows the entry for the liquid tight conduit. I drilled the hole in the window using a spade bit big enough for the conduit to go in. I connected the conduit to the switch box thus allowing me to turn the electricity off when on vacation.

STEP 7: And There Was Light, and the Light Was Good!

Finally I can set my tools to work in or around my shed. My dear wife will be very pleased that I move my noise making to the backyard. A future addition will be an outside motion light. I hope that the information will inspire you to do the same and give ideas.

Comments

[policealisa]

Enjoyable and entertaining read, and an excellent sense of humour.

[Davross106]

Could i run a wire to my shed and connet a socket snd light and just plug it in in the house when i want to yse it or do i need a breaker and would that be safe or unsafe

[Supertux]

Thanks for the help but is it legal.

[frugalguy]

Unfortunately, no.

[BlazeM4]

Is it okay to use 12-2 Romex inside the conduit as long as the sheathing is taken off? Conduit is approximately 25 ft flexible liquid-tight.

[frugalguy]

Absolutely not. Romex conductors are not rated for wet locations. A "liquid-tight" conduit that is outdoors or buried is still a wet location. Your Romex conductors will lose their insulation and short after a time. Use THWN or other wire that is rated for wet locations, and pull the individual wires through the conduit.

[frugalguy]

The NEC says the inside of any conduit in a wet location is itself a wet location.
The Romex says 'For Dry Locations' for a reason... that sheathing on each conductor will degrade in a wet or a damp location, and eventually short.
Either pull individual conductors rated for wet locations through the conduit, or else use a cable rated for direct burial. This will fail with a dangerous short eventually.

[sjc5454]

Why didn't you put a sub panel in the shed? Using 1.5" PCV pipe and running #8 wire would let you have up to 50 amps available and been much safer. You could have put a 50 amp breaker in your main panel and shut that off when you went on vacation. Then you could have made one half a workshop as well. You could have always lowered the amperage needed if you didn't plan on running many tools. I think this would have been legal in all states and actually been easier. Father was an electrician, learned from him, but that was 50 years ago, so some codes have probably changed. But the basic concept is still a better idea.

[pbesong1]

if you use cable made for underground direct burial, you don't even need any conduit except where the wire leaves the ground. so from the bottom of the wire ditch to wherever it attaches to above ground. I had a certified electrician install our 220 pool heater and that's how he did it. I'd also not drill thru the window. just drill thru the concrete block and tap in a pvc pipe to run the wire from an inside box to an outside box. The inside box might be optional, though. I've seen the wire just puttied around on the inside so it doesn't really touch the edges of the pvc pipe. But if you aren't an electrician, you can still do a job like this. Just try to do it right and check your local codes.

[Collector00]

Should be using THWN and not just unsheathe wire meant to be used indoors. No one should follow these instructions. Definitely not to any code.

[Mikyjo]

Cool. But I wanted to see the rock you dug up. :)

[Ozzilla]

A picture of the wiring inside the disconnect would be quite useful.

[crushs]

wrong wire used drilling threw a window sill wow so many thing are wrong here please dont wire a shed this way.. your going to burn shock or kill someone.. bet your insurance doesnt know about this does it

[deanbear]

Moved in to a home with a wired 16x20 out building. Not an old building that was built many years after the house. The power doesn’t work to the building. I assumed I could flip the main circuit and reset it hoping it was tripped. But nope that didn’t help, building lights won’t come and none of the outlets work. My question is could it have been wired and connected elsewhere to another power source? If so, how can I tell if I can’t notice a visible difference in wiring?

[JoshM267]

You shouldn't run NM-B within conduit, just run separate wires. Also why would you run it through the window frame instead of just drilling through the cinderblock?!

[RandyH89]

I’m coming from panel box in house across drop ceiling to outside then to shed panel box that has 3 outlets and 3 lights ..pvc buried 35 feet long can I use 12/2 or 14/3?? House wire??

[210megavolt]

running any type of electrical cables or conduits through window or door jambs is prohibited by the NEC

[210megavolt]

Minimum depth requirements depending on conduit used will range anywhere from 12 to 18 in, tables in National electrical code should be consulted.

[210megavolt]

Individual conductors can be purchased individually the exact length required for a lower price. depending on the length, the largest size may be required. Wire sizing tables in the National electrical code should be referenced.

[Rj3lambe16]

Although using liquidtight to bury might be acceptable by code, it still is far from professional. Using PVC or UF wire would be the professional way to wire a shed. Not to mention ising PVC would be much less of an eye sore if done correctly.