# Shop Wiring



## jbolt (Nov 30, 2018)

I’ll start by qualifying that I am a general contractor with over 30 years of experience in home building and renovation.  I’m well versed in household electrical so I’m good on means, methods, codes and safety.

In the spring of next year I’m having a local contractor insulate and drywall my new (to me) shop at our Oregon property. The shop is 28’ x 32’. It currently has a subpanel feed by a 60 amp breaker with #4 wire. There are 110v convenience outlets every 4’ around the perimeter walls about 4’ off the floor. These are divided on three separate 20 amp breakers.

I need to get the wiring sorted out before finishing the interior can begin and I’m waffling about the best way to proceed. My current plan is to run a feeder to another subpanel on the opposite side of the shop to feed the circuits on that side which would cut down the amount of wire needed to be run from one location.

All the 220v circuits would be surface run in conduit after the walls are finished. I just don’t know what the final equipment layout will be until we get up there full time in a few years so I think it is better to surface run.

The lighting wiring can be run in the walls but I’m debating whether to leave the 110v outlets in the walls or strip that out and run everything in conduit? I’m not a huge fan of surface run conduit but it makes the most sense to me for customization and expandability.

If anyone has been through something similar I would appreciate your thoughts.

As to lighting, for a shop of this size with a 12’ ceiling how many lights would you recommend? I like lots of light.


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## ttabbal (Nov 30, 2018)

Not nearly as big, but I recently installed a bunch of wiring in my garage shop with an electrician inspection. I ran a 100A subpanel from my main, it was reasonably accessible and if I'm pulling wire, might as well. I also have an EV charger, so that needed a bit of power. I think your plan to put another panel on the opposite wall makes a lot of sense and I would do that in-wall if you can. If nothing else, you avoid running into issues with conduit fill and derating pulling everything from the other side. And it's easier to add more conduit as needed, you don't have to go all the way around the building, just to the closer box. I already had to add another conduit across the ceiling due to that. 

I would leave the convenience outlets and add to it later with the conduit runs. Mine is done all with surface conduit, which IMO looks good enough if you are careful. 

I ran 2 MWBC circuits to the shop area, alternating every other box for 110V. So I can run higher power drain 110V loads without tripping breakers so much as they won't be sharing often. I couldn't run a vacuum and the miter saw before. Irritating. 

I already had a 220V 40A over there, but I added some lower amperage 220V for the mill and grinder so I can leave the larger one for welding. I also added a couple circuits on the garage side as we were always running out and there was only one circuit in there before. We'd managed to trip the garage circuit a couple times using things in the yard as well. Now that stuff has a pair of dedicated circuits to work with. 

I'd plan for lots of lighting. But it doesn't need a lot of power if you're going to use LED or fluorescent. If you want to do in-wall, you could set boxes and/or outlets in the ceiling on a grid and just use them as needed. I'm using LED and have loads of light only drawing about 2A.


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## JimDawson (Nov 30, 2018)

In a shop, surface wiring in conduit is the only way to go for everything IMHO.  It's easy to make changes and matches the later additions when you need them.  It's a little more work but worth the effort in the end.  Plastic conduit is cheap and easy to install, but use metal boxes.  Surface mount the breaker panel also.


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## Logan 400 (Nov 30, 2018)

The spacing for your outlets are typical for a general use shop layout. Unless they are  in the way of future wall mounted cabinets I would leave them as they are then surface mount dedicated circuits when size needed and location is determined. Your lighting question is more difficult not knowing the type of lighting you want. I have 10 2x4 3 lamp  florescents with an 8' ceiling and it is adequate but not great.
Jay


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## westerner (Nov 30, 2018)

Lighting- my shop is 24 x28, 10' lid, sheetrocked but not painted. 2 windows, 4'high, 5'wide, both facing southwest. Built the shop when I was 28 years old. At that time, I hung 4 two bulb flourescents. Plenty of light for me then.
Fast forward to today- I am 58, with great eyesight according to the Doc. I have 20 4' bulbs in there now, with 300W halogens on arms above 3 different workstations. Portable LED worklights and flashlights all over the place. Seriously considering a move to all LED, because I am at the limit of what my lighting circuits in the panel will support.


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## benmychree (Nov 30, 2018)

Although I did not do it in my home shop, I like to use gutters the full length of a shop, this I did when I wired my former shop downtown, that way, you can run suitably large wire the full length of the shop and tap into it at any point, and locate sub panels below it and run wire either direction inside to feed machinery as needed, it allows changes to be made easily at any time after the initial installation.


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## Dabbler (Nov 30, 2018)

If the 110v outlets are already there, I'd leave them.  

WRT lighting, I just went to 2'X4' LED panels.  The ones I bought were 5800 lumens, and for my 8' ceiling, I used 4 for general lighting in a 25' X 25' shop - yes 4.  Over the bench I used 2 800 lumen 8" X 8" panels and my bench is very well lit. Over my lathe I am re-purposing an 4X4' fluorescent fixture for use with retrofit LED bulbs, 300 lumens apiece.

Over my mill I'm thinking to use 2 double fluorescent fixtures wide spaced for general light around the table.  All machines have work lights, of course.

I like the idea of surface mounting your machine specific power.  I ran all mine in the walls and it isn't the best.


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## WCraig (Nov 30, 2018)

Is 60A enough?  What are your major power users?  Are you going to have electric heat or air conditioning?  Electric hot water heater?  Welder, compressor, dust extraction, ... ?  How many 220 machines?  Any 3-phase?

Do you foresee ever having more than one person working in the shop at a time?

I would think that with modern lighting, you could get good illumination without using a lot of power but I can't help with specifics.  Otherwise, your plan for 110 and surface mount 220 sounds sensible.

Craig


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## Dabbler (Nov 30, 2018)

My shop has 60A 220V feed.  I use a Miller 300A welder, and all my 3ph machines on it with no problem.  I can only use one machine at a time....


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## jbolt (Nov 30, 2018)

WCraig said:


> Is 60A enough?  What are your major power users?  Are you going to have electric heat or air conditioning?  Electric hot water heater?  Welder, compressor, dust extraction, ... ?  How many 220 machines?  Any 3-phase?
> 
> Do you foresee ever having more than one person working in the shop at a time?
> 
> ...



60A is plenty. The feed wire from the main is rated for 75 amps so I could up the subpanel to 70A. All my 220v machines are 25A or less with the welders pulling the biggest draw. Not planning to have employees so at most I would be running my CNC mill and another machine at the same time. I do that now on a 30A breaker. Shop will be heated with a gravity feed pellet stove. No power required.


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## Brain Coral (Dec 2, 2018)

"As to lighting, for a shop of this size with a 12’ ceiling how many lights would you recommend? I like lots of light."

Hello Jay,

I built my house/shop about 8 years ago. It is 26' x 36' with a 10'6" ceiling height. I ran a total of 7,  8' double fluorescent lights, for a total of 28,  4' bulbs. I ran two 8 footers, end to end, across the 26' span, then two more about 8' apart from strip to strip. I ended up with a single 8 footer at the end, where it was narrower because of a stairwell. I am very happy with the lighting, and am slowly converting the bulbs to LED. I just have to choose the bulb that I like the best.

Brian


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## ThinWoodsman (Dec 2, 2018)

Agreed on conduit - that's how I did mine. No sense in punching through walls to add/repair power in what is primarily a utility space. I ran steel flex along the floor from the wall to each machine, bolted some treated 1x6s to either side of the flex, clamped the flex to 1x6s with standard conduit two-screw clamps. Took care of the tripping hazard.

12'x24' with 9-foot ceilings. I used 8 Sunco Flat Shop Light LEDs, 4 per series, both series plugged into a single ceiling-mounted outlet. Plenty of light, easy to switch off ones you don't use. I mounted them with s-hooks into eye bolts, lets me remove lights singly if I need to extra head-room (hey, it happens).

I'd think 12 should do your space - maybe four runs of 3, and if that isn't enough you can add a fourth light to the end of each run.

They work out to about $25 a light on a'zon.


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## Latinrascalrg1 (Dec 2, 2018)

It seems your questions have received alot of good advice so i wont restate whats been said other then I too highly recommend LED lights in which ever design you like.  

My comment concerns the "Color" of the light in particular.  If you prefer a Bright light you will want the "Blue" Spectrum which is in the 4800k range.  If you like a softer less harsh type light thats typical of a "SOFT White" incandescent bulb you would want a Red Spectrum in the 6500k range.  Personally I like the 5,500k range for a nice daylight blend.  Hope that helps.


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## Dabbler (Dec 3, 2018)

I Like 5500K fopr general lighting, and 3600K for workbenches and closer in work.  I find the yellower colour gives less eye fatigue when I'm focusing in close.


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## jbolt (Dec 3, 2018)

Thanks for all the input. 

The more I think about I'm going to remove all the current romex and outlets and then run everything surface mount.  I'm having the shop insulated and it was originally built without a weather barrier under the siding so my insulator is going to spray a 1" layer of foam in each stud bay and fill the remaining space with blown in before the drywall is installed. Having the walls clear of obstacles will make for a better job.

Even with over twice the space I have now I want to maintain enough floor space to be able to work on a car or truck or other large project. Something I have never had. I'm toying with the idea of putting in a 4' wide storage platform around the perimeter walls 8' off the floor. If I do that I can run conduit and j-boxes on the wall under the platform and then put in drops where I'll need them.


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## ThinWoodsman (Dec 3, 2018)

jbolt said:


> I'm toying with the idea of putting in a 4' wide storage platform around the perimeter walls 8' off the floor. If I do that I can run conduit and j-boxes on the wall under the platform and then put in drops where I'll need them.



That's a pretty good idea. I'd probably go with 2-3' deep unless it's mostly for boxes - not going to be able to see anything towards the back, that high up. I did a few 18" shelves about 7' up, and being able to hang things off hooks mounted underneath is great. Might add a few more.


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## markba633csi (Dec 3, 2018)

Lower the K number the redder the light- 2700K is much redder than 6500K
M


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## MarkM (Dec 3, 2018)

When I set the garage up I tried to think about future events like a possible move and adding more machines.  A hundred feet from the house and added another forty feet.  My machines and heater are all done in heavy guage three phase teck cable even though there two phase exept for the lathe with three phase through a vfd.  I may add a rotary phase down the rd. with more machines.  My mill drill was done with welding plugs and enough cable for anywhere in the garage for a bigger welder down the rd.  I spent more money than I needed to that I didn t have.  I figure this way I have flexibility knowing there are more machines to come and that s when i ll see my return on doing it this way. We all have our ways of doing things And reasons why  Flexibility!!!


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## Superburban (Dec 3, 2018)

I would definitely put some research in the new LEDs. I saw some where they are not only dimmable, but you can change the color output. On the surface, at least they sound great. Put in more then you think you may need, and then just dimm them to your liking, and you can turn them up later if needed. But I know nothing about their longevity, or cost.


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## Jubil (Dec 3, 2018)

Recently found a sale on 8' v-shaped led lights. (10 8' lights for $225 with free shipping). 
My shop is 28 x 28 with a sloping ceiling from 15' to 10'. I put 4 of the 8' lights in half of the shop (auto/tractor/truck bay). Almost like daylight in there. Trying to decide best way to install in the rest of the shop. 
I personally like surface mount wiring.


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## Latinrascalrg1 (Dec 3, 2018)

Markba thanks for the correction, you are correct, I got that backwards.  I mixed up the Nanometer wavelength (at which 480nm is in the blue spectrum and red is in the 650 range) with Calvin readings.


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## markba633csi (Dec 3, 2018)

No problemo, I get turned around myself sometimes, senior moments
Mark


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## Holescreek (Dec 3, 2018)

Two of the handiest outlets in my shop are in the ceiling. One over my work bench island and one on the other side of the shop over a lathe.   I keep a pair of those short drop-cords plugged into them so I don't have to get a step ladder to use them.


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## gi_984 (Dec 4, 2018)

"In a shop, surface wiring in conduit is the only way to go for everything IMHO. It's easy to make changes and matches the later additions when you need them. It's a little more work but worth the effort in the end. Plastic conduit is cheap and easy to install, but use metal boxes. Surface mount the breaker panel also."

This, but I would use the metal conduit.  Current shop is wired in the walls with insulation and sheetrock.  Thought I put enough extra in for expansion.  WRONG!  Now I wish I had put everything external.  

I've got ceiling mounted outlets above each work area.  Would do again.


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## 4cyclic (Jan 10, 2019)

I chose all wiring in EMT conduit for my shop. Glad I did it that way. Bending conduit is not hard to learn and fun.


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