Quantity of outlets for 20x20 shop

[MrPink]

So I will be running 100a service out to my workshop that is 20x20, I will have separate circuits for the heater, the air compressor, and a 220v for my welder.

But I was thinking 3-4 15a outlets per the 3 walls, and 2 on the wall with the door. Does this sound about right?

 

[LOW1]

My view is that with that small amount of outlets I would go with 12 amp outlets as there would not be much cost difference.

And before I determined the number I would try to lay out my shop. Outlets hidden behind large objects that you put in front of them are not really usable. And consider the height of your outlets. Higher may be better for workbenches, etc

And now is the time to plan the number of circuits you want.

 

[rjacobs]

I have way more outlets than I need or could use, but I didnt want to run extension cords everywhere.

24x29 shop here, so not MUCH bigger than yours.

I have 4 down each side plus 3 down the back wall plus a quad outlet right at the breaker panel. I need to put in 2 exterior outlets before I get my spray foam done.

I used the Leviton hospital grade outlets which I am sure is overkill, but in the grand scheme they were like 7 bucks vs. 4 bucks for a "commercial" outlet.

 

[sz0k30]

My view is that with that small amount of outlets I would go with 12 amp outlets as there would not be much cost difference.

Don't you mean 20 amp outlets with 12ga wire?

 

[Stuart in MN]

My view is that with that small amount of outlets I would go with 12 amp outlets as there would not be much cost difference.

12 amp? I'm guessing you meant 20 amp, and in any case in the US you can use 15 amp receptacles on a 20 amp circuit as long as there's more than one plug, and a standard duplex receptacle counts as two. Also, 15 and 20 amp receptacles are identical internally, the only difference is the shape of the holes on the front.

 

[LOW1]

Yes Re 12 gu wire and 2o amp circuit. Too early for me today

And you can also use Harbor Freight instead of SnapOn

 

[Chuckster in NJ]

#12 Wire ran to 20 Amp receptacles…….. You will thank me later.

 

[Norcal]

#12 Wire ran to 20 Amp receptacles…….. You will thank me later.

There is no legitimate reason to spend extra money for 20A devices, if a piece of equipment requires a 20A attachment plug, a dedicated circuit would be required, using quality 15A receptacles are the best choice. over cheap residential grade devices.

 

[dscheidt]

I have way more outlets than I need or could use, but I didnt want to run extension cords everywhere.

this is the key thing for me. Having extra outlets also means when you rearrange the shop, if you decide that a shelving stack needs to go right in front of receptacles, it's not a big deal, because there are others. If you know what the layout is going to be, put receptacles in for fixed things, like your bench, cordless tool charging, drill press, TV/stereo, whatever. And then put general purpose outlets in. Make sure there's one just inside the over head doors, ideally on either side of it, so you can easily use something in the driveway or on the apron.

the other thing I like in work spaces is having two duplex receptacles at each location, with the two devices on different circuits. I put the left ones on one circuit, and the right side ones on the other. That makes it easy to know if you're plugging two high load devices into the same circuit, and if you're using them at the same spot, to split them out.

Also, common advice is to put receptacles well off the floor, so they're not blocked by a piece of plywood leaning on the wall or whatever. That's fine, but I want some low, because if you have a cord plugged in, the cord can create a tripping or navigation hazard.

definitely run 12 ga wire, on 20A breakers. 15A devices are fine, if you happen to get 20A ones at the same price, I'd use those.

 

[cannuck]

26 x 39 here. 120 every 5' over 2 x 25 work benches, 2 x 4 on end walls, but most used are a row overhead each 5' on ends of trusses that stop over 10 x 26 main vehicle bay. other duplex outlet on walls and 2 ov rhead also have a simplex 240 receptacle. Only 2 welder plugs (3 or even 4 + 1 outside would have been better. It's the overheads that avoid a lot of extension cord and my corded tools mostly have long leads.

 

[Steve W.]

So I will be running 100a service out to my workshop that is 20x20, I will have separate circuits for the heater, the air compressor, and a 220v for my welder.

But I was thinking 3-4 15a outlets per the 3 walls, and 2 on the wall with the door. Does this sound about right?

And before I determined the number I would try to lay out my shop. Outlets hidden behind large objects that you put in front of them are not really usable. And consider the height of your outlets. Higher may be better for workbenches, etc

And now is the time to plan the number of circuits you want.

There have been discussions here about layouts and circuits. Some will put a "quad" every so often on a wall and put each side on a separate circuit. That way you can plug in two devices in one location without overloading a circuit. Others will alternate circuits, instead of putting them in the same box. One quad will be "A", the next quad will be "B", etc. As mentioned by others, it makes sense to use a 20A breaker, but you only need 15A receptacles, unless you have a device that requires a 20A outlet. One thing that nobody has mentioned yet is that they need to be GFCI protected. You can put the GFCI device in the first location for that circuit, which will protect others that are connected to it, or you can get a GFCI breaker. The breaker is a bit more expensive, but not prohibitive. (I went with the breaker so my receptacles are all the same shape.)

My shop is 24 x 30, with a 10' overhead door on one of the long sides (north wall). There is a 12' bench on the same wall. I have one circuit that powers everything on that section of wall, which includes the "beer" fridge, TV, and a couple power strips for things I plug in while at the bench. The west wall has three quads, on a different circuit than the north wall. The south wall has a total of 6 quads, 3 each on two circuits. The east wall has the stairway to the attic, the bathroom and the shop sink. The bathroom and outlets by the shop sink are on another circuit. The attic has a few outlets, again on another circuit. Lights are on two circuits, one up and one down. Door opener on another circuit. An outlet has been installed for a welder that I don't have yet. And a couple outlets outside.

Yes, the box gets full rather quickly. And, yes, I do "overkill" quite nicely.

 

[75gmck25]

Since you already have the shop, you know what kind of work you do and where you would need electricity.

Start out by laying out your workspaces and where you would like to have receptacles of various types (120 volt above workbench, 240 volt next to welding table, 240 volt in the corner for compressor, etc.). Make sure the height works well (higher is usually better) and that they are not blocked by shelving units or stored items. Also take a look at the lighting layout, including any exterior lights you want.

Bottom line - plan your shop work and storage, and then set up the electrical to support your plan.

Also run some smaller conduit to the shop for low voltage wiring (phone, cable, internet, etc.). Much easier to do it all at once.

 

[mikedodge]

For that size 3 outlets per wall sounds like enough. Figure out where you want workbench and other stuff ahead of time.

 

[Chuckster in NJ]

There is no legitimate reason to spend extra money for 20A devices, if a piece of equipment requires a 20A attachment plug, a dedicated circuit would be required, using quality 15A receptacles are the best choice. over cheap residential grade devices.

The 15 amp devices will work just fine but a 20 Amp device in a garage is better and the OP is not looking on a big price difference because of the number of devices.
A 20 amp device will "hold/grip" the cord cap and keep it from pulling out and it is engineered/tested for a heavier load over a 15 amp device PLUS if you ever have a compressor or appliance with a 20 amp cord on it the device is ready.
All receptacles in a garage must be GFI protected and Tamper Resistant.

When I wired my garage I used 15 amp Hubble Spec Grade receptacles ($$) because I had some left over from a job otherwise I would have used 20 amp devices.

 

[mike93lx]

The 15 amp devices will work just fine but a 20 Amp device in a garage is better and the OP is not looking on a big price difference because of the number of devices.
A 20 amp device will "hold/grip" the cord cap and keep it from pulling out

Huh? The guts on a 20 are the same as a good quality 15, just have the provision for the horizontal prong, which is basically never needed

 

[dscheidt]

A 20 amp device will "hold/grip" the cord cap and keep it from pulling out and it is engineered/tested for a heavier load over a 15 amp device

15A receptacles are built to the same electrical and mechanical standards as 20A ones, 20A just get the extra T on the neutral. Spec grade 15A and 20A receptacle from the same manufacture are likely identical internally (often including the contacts for the 20A plug.) Remember, a 15A receptacle can supply 20A total to both outlets at the same time, so they're built to do so. Stay away from the 50 cent contractor specials, of course, because they're junk.

 

[Jeff Ivers]

If the building is just for storage, the number of outlets proposed is fine. If you are a DIY hobbyist, you will find, over time, that the number of items you wish to have plugged in just keeps growing and the number of outlets becomes way too few. Examples - disk sander, workbench close up light, chargers for cordless tools, stereo, TV, carbon dioxide detector, welder, chop saw, miter saw, extension cord for whatever corded tool is currently in use, dremel tool, trickle chargers, and on and on. And what about wanting to plug in a portable electric heater - you need 15 amps and nothing else plugged in on the circuit.

 

[Jlanciani]

I didn't see it mentioned yet but I'd also put at least one exterior outlet on each wall for added flexibility.

 

[tarbellb]

You may want to consider HEIGHT of the receptacles, in shops I find the typical residential height to low for practical use
Also do some planning around where you might want certain tools, just spacing them evenly isnt always the right move.
Keeping a outlet close to the shop doors is helpful too.

Also run #12 wire and 20amp breakers, there is always a tool that likes to pop those 15amp breakers on #14g

 

[Codyboy]

There is no legitimate reason to spend extra money for 20A devices, if a piece of equipment requires a 20A attachment plug, a dedicated circuit would be required, using quality 15A receptacles are the best choice. over cheap residential grade devices.

Yes. Yall all talked me out of 20A (moar power arrggghhaaag)
I went with 15A on 12awg wire.
Dual gang receptacles about every 4 or 5ft and about 4ft high.
I'm loaded with outlets!

I also put them on MWBC wiring. Which came in handy as I already had to convert one over to 240v for my unisaw.

I used 4x4 metal boxes and they are grounded. Devices are self grounding. No i didn't run a pigtail to the device.

 

[Spindifferent]

Keep it simple: a quad in each corner and a dual at each wall midpoint and maybe an extra dual near the door; all 15A.

 

[MrPink]

Since you already have the shop, you know what kind of work you do and where you would need electricity.

Start out by laying out your workspaces and where you would like to have receptacles of various types (120 volt above workbench, 240 volt next to welding table, 240 volt in the corner for compressor, etc.). Make sure the height works well (higher is usually better) and that they are not blocked by shelving units or stored items. Also take a look at the lighting layout, including any exterior lights you want.

Bottom line - plan your shop work and storage, and then set up the electrical to support your plan.

Also run some smaller conduit to the shop for low voltage wiring (phone, cable, internet, etc.). Much easier to do it all at once.

Too far to run Cat cable for internet, shop is 80-100yrds away from the house I'm doing a line-of-sight wireless antenna type setup for Wi-Fi out there. Have 0 need for phone cord out there. and i havent had cable in years.

i planned on a 3.5ft- 4ft height for my outlets already. i appreciate your input.


I plan on sticking with 15A outlets as i have 0 need for 20A, I don't run anything that requires that. my compressor is 13A draw, my welder will be on it's own 220V, heater is 30 or 50amp( i have to check)

 

[Codyboy]

Too far to run Cat cable for internet, shop is 80-100yrds away from the house I'm doing a line-of-sight wireless antenna type setup for Wi-Fi out there. Have 0 need for phone cord out there. and i havent had cable in years.

i planned on a 3.5ft- 4ft height for my outlets already. i appreciate your input.


I plan on sticking with 15A outlets as i have 0 need for 20A, I don't run anything that requires that. my compressor is 13A draw, my welder will be on it's own 220V, heater is 30 or 50amp( i have to check)

300 ft is too far for cat 5e?

 

[mike93lx]

300 ft is too far for cat 5e?

100m is considered the max, but well terminated with good quality wiring can do longer

 

[75gmck25]

My point is that you should future-proof it by running a 2nd conduit (with pull string) for low voltage wires. It is a cheap install when you already have the trench open for electrical conduit.

 

[Ultradog MN]

So I will be running 100a service out to my workshop that is 20x20, I will have separate circuits for the heater, the air compressor, and a 220v for my welder.

But I was thinking 3-4 15a outlets per the 3 walls, and 2 on the wall with the door. Does this sound about right?

Surface mount your panel then wait till you get the interior walls insulated and paneled with whatever you're going to use.
Then run everything on the wall with thin wall conduit.
You will not regret it.
I have 5 120v circuits. Only 1 is 15 amp - it powers the furnace only. All the others are 20 amp.

 

[Codyboy]

100m is considered the max, but we'll terminated with good quality wiring can do longer

So not even at the limit yet.
I'd run it.
Can still do line of site antennas or whatever but id still install the conduit for a hard line. Can also do fiber. Even moar better!

 

[sparky 1971]

I'd probably put one in the middle and another about two to three feet in from each corner on three walls and probably none on the wall with the OH door unless it has two doors, then one in between the doors; most of them will probably never get used. For myself, I'd probably split them up between two 20 amp circuits and be happy since the compressor is dedicated. A person can only do so much at a time.
Even though I put them in, I don't know how many receptacles are in my 20X30 but other than where the battery chargers and radio are plugged in, I really only use two and those are because the retractable reels are plugged into them.

 

[welder4956]

So I will be running 100a service out to my workshop that is 20x20, I will have separate circuits for the heater, the air compressor, and a 220v for my welder.

But I was thinking 3-4 15a outlets per the 3 walls, and 2 on the wall with the door. Does this sound about right?

Sounds about right for a workshop, but be sure to put 2 or 3 where the workbench is located and outlets for stereo, tv or other such items up high.

 

[PCustoms]

So I will be running 100a service out to my workshop that is 20x20, I will have separate circuits for the heater, the air compressor, and a 220v for my welder.

Anyone mention yet 100A is overkill?

If feeding from the house save some $$$ and go smaller...

 

[Stuart in MN]

Considering the popularity of battery powered tools these days, how many things do you have that need to be plugged in to the wall?

As far as that goes, I don't have nearly as many receptacles as most people here recommend, and there are a few of them I don't think I've ever used in the 30 years since I built my garage. Put several where your workbench will be, then a couple more on each wall and it will probably be plenty.

 

[beltfeed]

Also run #12 wire and 20amp breakers, there is always a tool that likes to pop those 15amp breakers on #14g

This! I have a 9" angle grinder that will trip a 15-amp breaker all day long when I lay into it as will my 1.5HP Baldor pedestal buffer and 120-volt Miller MIG. 20 Amp receptacles and breakers with 12 Ga wire and 10 Ga wire for bigger shop with long runs.

 

[Dagny]

Pole barn steel inside. thin wall fore sure.

 

[willf650]

I have a 30 * 36 pole barn and put two duplex receptacles on every column on two separate 20 amp circuits. Due to the dual 20 amp circuits at every location I think I have 6 circuits On the walls and another in the ceiling for 4 cord reels.

It was overkill but I wanted to be able to plug a portable compressor in at any location and still have a usable circuit for other uses.

You can put 15 amp outlets on a 20 amp circuit and I would run nothing but 20 amp circuits if it was me.

 

[willf650]

My point is that you should future-proof it by running a 2nd conduit (with pull string) for low voltage wires. It is a cheap install when you already have the trench open for electrical conduit.

I ran two 1 1/2” conduits and a 1” to my pole barn. It’s easy and cheap to have an extra pipe while the trench is open. It’s painful after the fact.

 

[Model A Fan]

I'm kind of an overkill guy. I did 2 receptacles in each box every 6-8'. I didn't know where I'd be building work benches or plugging in stuff, so I just overdid it. Cost extra, but not that much compared to frustration of having to hunt down a place to plug in a grinder, shopvac, etc. I got the outlets on super sale from Amazon, so everything is wired in with 12AWG Romex and 20A outlets. I think I got the outlets for less than $10/box of ten. Now they're $15, but still a good price. Super Cool Orange Outlets

 

[dave*99]

If you have an open trench and a 100 yrd run, the most reliable and easiest option for network connectivity is fiber.

 

[dave*99]

100m is considered the max, but we'll terminated with good quality wiring can do longer

It's an interesting topic. As you say it can operate beyond 100m, it's beyond the specification, and there are some considerations.
If you have other options it would not be a first choice.

Why Can't Ethernet Cables Exceed 100 Meters? Unpacking the Truth Behind the Limit - Blog - - VCOM International Ltd

Discover why Ethernet cables are limited to 100 meters due to signal attenuation and interference—explore if it's absolute, extensions, and tips for reliable networks.

www.vcom.com.hk

 

[MrPink]

Anyone mention yet 100A is overkill?

If feeding from the house save some $$$ and go smaller...

I am going to also be adding a maxjax lift out there at some point too so I'd rather have enough ran out there then not enough.

 

[mike93lx]

I am going to also be adding a maxjax lift out there at some point too so I'd rather have enough ran out there then not enough.

You still don't need 100a.

What are you doing for a feeder?

To be clear, this is just the feed size we are referring to, not the panel. The panel can be larger and you absolutely should give yourself lots of space