wiring

[hardscrabble]

I recently put up a post frame shed, 40x72x14 with cement slab, mainly for storage, but I will be putting a workbench and my tools in there, also. I haven't got it wired yet. I'm wondering how many outlets should I have? I plan on one 220 in case I decide to get a welder, and 110s about 10 feet apart. Is that too many, or not enough? I would like to avoid extension cord usage as much as possible.
Thanks for any input.

 

[Awlknottedup]

I just finished wiring my existing 24 by 32 pole building shop. When I started it had 100 Amp service with two outlet circuits each with 20 Amp breakers, one for the west and one for the east wall with an outlet on each pole all with 12 ga wire.

I added several circuits. The south wall has a GFCI that feeds an outlet of both sides of the sliding door a dual outlet over the workbench, an outlet beside the bench for the drill press and another on the corner. There are also two outlets hanging from the ceiling.

The north wall has a GFCI feeding an outlet on both sides of the man door a dual outlet over the bench and two more on that wall plus two hanging outlets. I think that no point in the shop is more than 8 feet from an outlet.

The shop had an existing lighting circuit so I pulled circuits for motion detector and task lights off that. I also added a 220 outlet for the Unisaw and a 30 Amp for the RV.

I also added a sub panel with 220V breakers for a welder. air compressor, and a dust collector.

Keep in mind that this is a single person shop.

 

[NCWayne]

I'd put them a maximum of 8 feet apart as most cords seem to be around 5 feet or so long. Too instead of putting in single recepticals do each box as a double. It's amazing how many times you need to use a receptical and there is already something like a battery charger for the cordless, or a shop light, or both plugged in. This way you've got the extra outlet to plug in the item you need at the moment. On the same note you never know when your gonna have something setting in front of one of the other outlets and aren't gonna be able to get to it easily. Now, if you do decide to run doubles I'd run everything with #12 and use 20 amp breakers instead of the usual #14 with a 15 amp breaker just so you know there is enough juice when you need it.

 

[paul]

Plan for it, if you can't afford it all now, plan for adding some wiring downthe road.

I did about the same building, tad bigger. We put 5 outlets around the sides grouped more by the work area, and a couple off in the far area. Put in a 200 amp box because it doesn't cost much different to do that the first time, and a 220v. I can add what I find need later, but it's set up to be usable & expandable withont having to redo what is there now. Use 12 gauge, 20 amp outlets, etc.

--->Paul

 

[Anonymous-0]

I thought I read somewhere that they reccomend having outlets every 6' apart.

 

[rossow (mn)]

I put up a 40x72 several years ago and put a 110 outlet on every pole (9 feet apart, I recall), plus on each side of each door, plus several overhead on the truss bottoms. I also have 220 and a phone jack in one corner. Remember, no one ever said, "D a m n, I have too many places to plug in."

 

[showcrop]

I would plan on twice that many in the area where I plan to have my shop.

 

[bc]

I'd probably run 3 20 amp receptacle circuits. One for back half of building and 2 around the work bench and other half with those around the bench wired alternately like a kitchen circuit. I'd want 3 sets of two side by side double receptacles with one set on each end of the bench and one set in the middle. One of set wired by a separate circuit. That gives you 12 receptacles around the the bench. Grinder, drill press, trouble light, radio, couple battery chargers, air compressor, extension cords, and all the other power tools that need a plug in add up.

 

[gregk]

That is strictly a matter of taste. If you are like me you can only use one tool at a time.(short of abattery charger or a space heater) Most tools have 6' cords or so, however to be efficient put a plug strip on the front of the workbench so your cords are not dragging across your work and getting tangled up in your "stuff". When I wired mine I put two circuits along the wall with my workbench and one for each side wall. Also a 50 amp 240 volt circuit for a welder and a 30 amp 240 volt for a air compresser. good luck

 

[Scott.ID]

8' on bare walls, 4" over the benches. 1 just inside of every entrance door, 1 on each side of roll-ups.

When I wired my shop 2 years ago, I think I calculated about 5 bucks per outlet for the wire, box, outlets, and a cover.

 

[David G]

The one outlet per post will work. That will get you to about one outlet per 8'. I limit to 4-5 outlets per breaker. You do not have to worry a lot about loading if you are the only person using it.

 

[David G]

The outlets should be GFCI on concrete or dirt. The GFCI breakers seem to hold up better than the outlets.

 

[Pair-a-dice farm]

I would also put a few outside just in case. I sometimes need a battery charger for when I'm forgetful and leave the lights on. oops

 

[Paul from MI]

If you are not sure how you are going to use each area of the building, I'd go easy on the number of receps on the walls. A 40' wide building means that anything in the middle is 20' from any wall. Having a recep every 9' won't do much good if you need to charge a battery in the center of the building, you'll need an extension cord anyway. In the area of your shop I would look at a recep every 6' or so for hand tools. When you get set up you can add wiring to your stationary tools, drillpress, saws, etc. as needed. You can always easily add receps later as needed.
As far as service capacity is concerned, put in as much as you can afford. I have a 60 amp in my shop, but I'd put in a 100 amp minimum if I was to do it again. Didn't have any money 35 years ago, and I've gotten by very well on it but more would be better. Depending on how far you are from your power source(house panel, maypole, etc.) take voltage drop into consideration when you determine your feeder wire size.

 

[Jiles]

(quoted from post at 19:35:41 03/27/11) I thought I read somewhere that they reccomend having outlets every 6' apart.

I think you are correct---You should be within 6 foot of an outlet on any wireable wall.

 

[Bob]

(quoted from post at 22:30:45 03/27/11)

(quoted from post at 19:35:41 03/27/11) I thought I read somewhere that they reccomend having outlets every 6' apart.

I think you are correct---You should be within 6 foot of an outlet on any wireable wall.

Actually, with outlets 12' apart you will always be within 6' of an outlet.

(NOT saying that a minimum amount of outlets is GOOD, and CONVENIENT, though!)

 

[MarkB_MI]

My shop is quite a bit smaller than yours, 30x40. I put a duplex outlet (four receptacles) on every side post and I've never thought I have too many outlets. In fact, I ran out of outlets on one post and had to add a second box.

With a wide building like yours, you can have the walls covered with outlets and it isn't going to help you in the middle of the building. I made up a heavy-duty extension cord: 12 gauge power cord connected to a duplex electrical box. The cord is long enough to reach halfway across my shop, so wherever I'm working I have four outlets handy.

As stated before, GFCI is a requirement for all your 220 outlets. Best to use a GFCI circuit breaker rather than GFCI outlets.

You should plan for at least two 240 outlets. One 50 amp for a welder and one 30 amp for a compressor. (Few compressors require 30 amps, but the 10 gauge wiring will ensure quick starting.)

 

[fixerupper]

A plug-in on every pole is handy even if it's only on one side of the building. 33 years ago when our 54X90 was built I put plug-ins on a few poles but not all of them. Now when I go to use one there will be some machine parked close to it making it inaccessable. There's nothing parked by the next pole but it doesn't have a plug-in. Power distrubution is important too. When this building was built I only had one diesel to plug in. Today four diesels reside in there and I have popped a breaker by plugging too many of them into one circuit. Not a good wat to start the day when to all of the diesels are cold in the morning. Jim

 

[JML755]

(quoted from post at 12:14:05 03/27/11) I recently put up a post frame shed, 40x72x14 with cement slab, mainly for storage, but I will be putting a workbench and my tools in there, also. I haven't got it wired yet. I'm wondering how many outlets should I have? I plan on one 220 in case I decide to get a welder, and 110s about 10 feet apart. Is that too many, or not enough? I would like to avoid extension cord usage as much as possible.
Thanks for any input.

I wouldn't go crazy with outlets every 6'. Every 12' would be plenty and if it was my place, I'd put 3 quads on each side wall (18' apart) and a couple on each end wall. And I'd have a quad outlet box at the front and just under the top surface of my workbench, not on the wall behind it. That would just be MY preference.

If you're going to plug in battery chargers or fixed equipment (grinders, saws, etc) then wall plugs at the right locations are great to avoid using extension cords on stationary tools. But one of the things I grab when I start a project in my shop or garage is a couple of 25' extension cords and a HD power strip. I can't imagine trying to work on something like a car, tractor or any other project and requiring my angle grinder, drill or portable saw to be within 5' of a wall outlet to be usable. JMHO

 

[buickanddeere]

Any other built in wiring hazards around your shop?

 

[Owen Aaland]

When I was building my shop I was told to determine the maximum amount of outlets I could imagine using at one time and then put in twice that amount. In the 30 years since it has proven to have been very good advice.

 

[Dusty MI]

The 12' rule is for in a/all homes.

Dusty

 

[Crem]

I have found that it is nice to keep the outlets at least 4' above the floor. I have run into projects where I temporarily laid 4 X 8 pieces of plywood or steel sheets against the wall and if mounted too low the outlets are covered or can be damaged.

 

[IH2444]

Get the good 20 amp GFCI receptacles and they work better. The 15 amp ones not so good.

 

[MarkB_MI]

Excellent point, Crem. I put my boxes 4 feet up from the floor. But then I built a plywood rack that raises the sheets up another 1-1/2 inches. Duh! I guess I need to raise those two boxes a couple of inches so I can use the bottom receptacles again.

 

[JML755]

B & D: Don't like the "duplex hanging off romex"? :lol: I kind of cringed when I saw it too. For the life of me I don't see how that is handy. If it's low enough to easily reach and plug something in, then I'd be walking around bumping my head on it all the time. And if it's high enough so people (and things) don't whack into it, then I'd need a ladder or stool to reach it. Not very convenient. Plus any hand tool (drill, etc.) that you plug into it won't have much usable reach if it's got a typical 5' cord. Work piece would have to be directly underneath it. If someone REALLY wants electricity in the middle of a shop, a better solution is to get a retractable reel with an extension cord on it and hang it in the middle of the shop. But for me, a 25' extension cord will just about reach anywhere from a wall outlet.

Like Mark_B, I've made up a quad outlet extension box with 12ga SO cord and Hubbel strain relief cord grip.

 

[Brian Jasper co. Ia]

Just in case B&D's comment wasn't clear, Romex is not made for applications where it is subject to frequent flexing....