# Running power to detached shed shop



## nogeel

I have a 20×12 shed on cinder blocks that I am using for my woodshop. Right now I am running an extension cord to the shop from an outdoor outlet which is a pain.

For this to fit in the budget I need to do the vast majority of work myself. I will get a Licensed electrician to finalize any plans before I do anything (and possibly do the final hookup and check) Before I hire a licensed electrician to approve a plan/give advice I wanted to see if my theory would work rather than waste money I could spend on router bit, saw blades, hand planes, etc.

I want to run a 40 A or 50 A subpanel that I can put a 3×110's (1 circuit for lights (possible a heater or portable A/C), 1 for a tool, and one for a 110 shop vac or dust collection) and 1 (or 2 if your aren't supposed to daisy chain 220V outlets) if I get future tools that use it.

The previous owners run to 3/4" PVC conduits underground to the shop already after a failed attempt at running power for lights from my utility room to the shed. My dryer is on a 220/230V 50 Amp circuit could I feasibly split that circuit to feed a subpanel in my shop? My dryer is in use maybe 1-2 days a week and according to the manual only has to be on a 30A breaker.

Also, it is about 60 - 70 ft from the house to the shed. Can I get by with 10 AWG wire to feed a 40-50 Amp subpanel at 220? Would it need to be four strand?

Again, I will get a licensed electrician or codes involved before I do anything


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## hotbyte

Not an expert, but I think you will need to get down to 4 or 6 awg. Yes on 4 conductors for a subpanel in detached building because you need separate neutral and ground. Also, from some shopping I've recently done, I don't think you will find a 50amp box that will hold that many circuits. Most seem to only have 4 spaces and will hold 8 110 circuits by using those double breakers. But, not enough room for several 110 and a 220. I'm going with a 100amp.


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## dustyoldman

My advise is to ask an electrician so that you will be doing this according to code


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## rwe2156

+1 Dusty.

I know you're not supposed to have more than one wire on a circuity breaker, but I've done it and not had a problem.

You can open up a couple slots to add a double pole breaker in your service panel by converting 4 120 V circuits to 2-120V split breakers. This will open up two slots for a 50 A DP breaker to your shop.

Wire size is usually determined by the breaker (or vice versa) so for a 50A you're probably looking at #6. 
I know a 50A is oversized for #10 wire.
I would check the wire size to your dryer and see what it is.

For that distance I don't think you'll have a big voltage drop.
Check around for supanels. I have one with 3 double poles and 2 single pole breaker.

You can daisy chain a 240V circuit to mutilple machines, but for thing like a big compressor or DC you need a dedicated circuit.

Then run everything by an electrician.


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## canadianchips

You are on right path.
Another question to ask ? Is the service into your house large enough to handle 60 AMP sub-panel ?


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## TheFridge

Pretty much no for almost all of that. Hire an electrician bud.


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## hotbyte

OP said twice he is going to involve a licensed electrician.


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## RichardHillius

My advise is to call around and find a electrician that will quote the job and talk to him about parts you can do yourself to cut down on costs. Some will work with you and some may not but you should be able to find someone who is willing. At the very least a quote will give you a idea of the scope of the project and how much it's going to take to do it right.


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## JayT

+1 to Richard H

Part of the issue is what your local building codes do and do not specify and what work can be done by the homeowner vs a licensed professional. In general, those codes will follow the national standard, but localities can place their own requirements. Even if one of our recommendations is safe, it may not be legal in your particular area.

Since you are going to hire an electrician for part of it, it's best to get them involved from the beginning. Some will not want homeowner involvement and may actually charge more than if they did the whole job. One that is willing to have you do some work will be able to spell out what you can do to save him time & money.

You might also be surprised by cost (don't know if you've had the job quoted, yet). A friend of mine built a house and was planning to run the electrical himself. He talked to an electrician about doing just a couple things and got a quote for the whole project that was just barely over what he would have spent on just the materials, so had the pro do the whole job.


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## wapakfred

You will not get by with #10 wire for 40 or 50 amps…at least not safely. The subpanel in the shed would be the easiest approach, then you can run your own circuits inside the building once the service is connected. The 240V receptacles can be daisy chained. There is probably a way to get a dedicated breaker to feed the shop, you don't want to try and load up on the dryer breaker. I think asking an electrician is the way to go.


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## HokieKen

I'm with Richard H and JayT.

Find an electrician who will spend a couple hours drawing up a schematic for you on how to do it to code and who will spec. all the parts you need and get you the parts at his cost (if you want him to) for $100 or so. I know several electricians and most, if not all of them, would be happy to make some easy money without having to break a sweat or use a tool.


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## WhyMe

No you can't use the dryer circuit to feed the sub-panel. Sub-panel is to be on it's own feeder. And for 50A you need at least #6 copper UF or #8 copper THWN in conduit or #6 aluminum in conduit. If your locality follows the IRC (International Residential Code) then you cannot daisy chain 240V outlet greater than 20A. IRC limits multiple outlets on a circuit to 20A. 30A and up need to be on single circuits. IRC E3702.5


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## TheFridge

> OP said twice he is going to involve a licensed electrician.
> 
> - hotbyte


No shlt.

15 yrs exp here. I'd suggest you just go ahead and talk to one if you were going to do it anyway bud.


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## hotbyte

He was just looking to become more informed for when he talks to electrician not get chastised for asking a question…



> OP said twice he is going to involve a licensed electrician.
> 
> - hotbyte
> 
> No shlt.
> 
> 15 yrs exp here. I d suggest you just go ahead and talk to one if you were going to do it anyway bud.
> 
> - TheFridge


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## Blackie_

Sub panels are cheap and you should be fine with #6, no smaller if you plan on running 240 volt. I just upgraded my shop from a 30 amp using #10 to a 50 amp using #6 feeding an 8 space sup panel one double pole breaker in the sub is dedicated to my 240V window unit.

canadianchips has a good point, but… if you're not running everything in the house at once you should be OK, the electrician will be able to help you here.


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## TopamaxSurvivor

You are on the right track getting a pro. You should b e OK with #6 or 8 Cu, #8 neutral, and #10 Ground in the 3/4 conduit. Your Voltage drop should be OK. Don't scab off the dryer circuit. Come directly off your main panel. Daisy chaining 220 outlets is ok for a circuit with 220 receptacles, not hard wired equipment.


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## crank49

+1 to what Topo just said.
Voltage drop for 60 ft run of #6 copper wire at 50 amp load is 2.651 volts.
That is about 1.1%; well within acceptable 3% limit.
I installed a 100A box in my shop and found it to be the most economical choice.
My box came from Home Depot in a kit that had the box and 5 breakers for about $50.


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## TopamaxSurvivor

I usually allow a bit more length to cover the drop from the transformer. Code doesn't really require it, but starting motor loads it will make a difference if you get more drop than the code requirement accounts for.


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## WhyMe

> *Daisy chaining 220 outlets is ok for a circuit with 220 receptacles*, not hard wired equipment.
> 
> - TopamaxSurvivor


That statement in itself is wrong because it's too general. Code varies as enforced in different areas of the country. Read my post #11.


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## TopamaxSurvivor

That is based on the National Electrical Code. All local jurisdictions can have their own codes that exceed the NEC. His electrician should know if that is the case in his location. I went through this for the owner of an airplane hanger just before I retired. I thought it was illegal, but he got his multiple outlets ;-) I can't remember if it was a 20 or 30 amp circuit.


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## nogeel

I am going to just get the electrician I met with to do it. The price was a lot cheaper than I expected. Good guy who seems to be willing to help me save cash where I can. Where is the best place to buy 500 ft of 6 AWG THHN wire? He said if I dig around I might be able to find a place cheaper than he can get it.


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## TopamaxSurvivor

Just have to call everyone. Most wholesalers in this are sell to individuals. Commodity items are usually priced fairly consistently, at least here unless you are getting a quote for a big job. When shopping for quotes don't be surprised if you get a lack luster reception to quoting 500 feet of #6. The wholesalers normally deal with shops that annually spend between $50,000 & $100,000 per man on the staff.


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## MrRon

I had the power company run a new service to my shop feeding a 200 amp panel. Although I will never see 200 amps being used all at the same time, I know I can run anything I want without worry of tripping breakers in the house. The most I have run at one time has been a big air compressor, a 220 welder, 220 saw, lots of lights and an air conditioner with no dimming of lights. (2 people working).


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## WhyMe

> That is based on the National Electrical Code. All local jurisdictions can have their own codes that exceed the NEC. His electrician should know if that is the case in his location. I went through this for the owner of an airplane hanger just before I retired. I thought it was illegal, but he got his multiple outlets ;-) I can t remember if it was a 20 or 30 amp circuit.
> 
> - TopamaxSurvivor


First I assume the airplane hanger was not on a residential use property. Second the NEC is mute to the fact of approving multiple 30A outlets on a single circuit. So please cite the NEC section approving multiple outlet circuits greater than 20A.


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## TopamaxSurvivor

If it is mute, it is allowed. In that case there is no section limiting the amperage of multiple outlet circuits; therefore one could have multiple 100 amp outlets on at single circuit is so desired.

The hanger was not residential occupancy for sure;-) That is just where I happened to be when I thought it was not allowed. It is, any occupancy as I recall. Applying the NEC is not a casual pursuit for the layman. Even the inspectors argue it constantly ;-))


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## MT_Stringer

@OP - Have you got your sharpshooter shovel sharpened and ready to go? You are going to get tired of digging.


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## WhyMe

> If it is mute, it is allowed. In that case there is no section limiting the amperage of multiple outlet circuits; therefore one could have multiple 100 amp outlets on at single circuit is so desired.
> 
> The hanger was not residential occupancy for sure;-) That is just where I happened to be when I thought it was not allowed. It is, any occupancy as I recall. Applying the NEC is not a casual pursuit for the layman. Even the inspectors argue it constantly ;-))
> 
> - TopamaxSurvivor


You are missing the whole point of what I'm saying. Because the NEC doesn't address multiple outlets on a circuit in excess of 20A does not mean it's allowed everywhere. There are other controlling codes and the IRC does state that multiple outlets are not allowed on a circuit greater than 20A. I believe a lot of states have adopted the IRC. I can only speak specifically to Virginia and multiple outlets on a single circuit 30A or larger is not approved for residential use. This applies to garages or shops on residential property, not just the dwelling. Whether this code is enforced or not is another whole matter.


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## TopamaxSurvivor

Yup, I certainly did. I don't know anything about VA. That is true many jurisdictions have codes beyond the NEC. The NEC is a universal code pretty much the basis for the US and Canada. Any discussion here is pointless if the reader does not realize local codes can be more restrictive.


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## Woodmaster1

I ran a separate service for my detached garage. At 200amps no problems adding any outlet in the shop anytime it is needed. I was lucky the pole was 5 feet from the garage. This made my run easy and cheap.


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## nogeel

Yeah, I was going to have a friend help with the digging, but a small trencher for 4 hours is about the same price as 2 trenching shovels. So I may let a machine do it.


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## TheFridge

Make sure you have utilities marked first to cover your butt.


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## soob

Shovel-I had to dig mine with a crowbar. Good exercise at least.

You really want two shovels-a drain spade or a digging bar for breaking the soil up and a trenching shovel for removing the dirt-something like this: http://www.homedepot.com/p/Razor-Back-47-5-in-Wood-Handle-Trenching-Shovel-2594600/204476143


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## Smitty_Cabinetshop

Wow, and I thought SawStop threads were contentious. Talk NEC and things get interesting real quick!

Good luck on your project, Jeff. Sounds like it's under control, hope it stays under budget.


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