Garage Electrical Advice

[beloitdavisja]

Family and I just moved into our new house and I'm adapting to my new workspace in the garage. It's 2 car garage with a little extra workspace on the side. The agreement with my wife to convince her to move is that she gets a parking spot inside.

Now that we've closed on our old house and the holidays are done, I'm going to call an electrician to come and run a few more circuits. Currently there's a single 15 amp circuit of outlets - not gonna cut it. My guess is they'll put a subpanel in and run the circuits from there. My bare minimum requirement would be to have two 20-amp circuits (in addition to the 15amp one) with new outlets around the wall alternating which circuit they're on. All my machines are 120, and I'm not currently planning on getting any that run 220. I figure there'll be room in the subpanel for it if I decide on it later.

My questions are pretty generic - any advice on what I should ask for? What kind of questions should I be asking the electrician? I have no idea what code would allow.

 

[bowman]

I don't know what machines you have, what you plan to run simultaneously, etc. That would determine the size of the wiring to the subpanel and the breaker installed in the master panel.

I would run a minimum of 40A subpanel to the garage using 220V delivered to the panel. I would go with minimum of 10 panel spaces for breakers. From the new subpanel, you can run circuits individually as 120V as needed, but will have 220V when you get to that stage.

 

[ScottM]

In addition to having at least one 220 circuit, you need at least two 110v 20 Amp circuits. As Neil said there will be times when you need to run multiple tools.

 

[McRabbet]

I believe that code requires any outlets in garage spaces to be GFCI (ground fault).

 

[ssmith]

Presumably the main panel isn’t in the garage and that’s why you need the subpanel.

Good advice from Neal on the core service at the subpanel. In addition you may want to consider;

- bumping to 60A service if you think you may feed a future heater or ac system in the garage.

- go ahead and install a couple of 220V / 20A outlets. Your intentions may not include 220V tools but that could change later plus, if any of your current tools are 115/230v convertible you may choose to switch them over down the road. Convertible tools run better and cooler at the higher voltage.

- install boxes for plenty of lighting in the ceiling.

- install an outlet in the ceiling for a cord reel. That’s proven to work well for me and perhaps would for you too.

 

[llucas]

Well, I think circuits are like shop space and clamps...you can never have too many. I would definitely plan on more that one 220v circuit for when that 220v bargain on craigslist pops up.
And remember to have the overhead lights on a separate circuit from you machines....you don't want to lose power to a machine and have the lights go out at the same time.

 

[Melinapex]

When we built our house I got the single garage for my shop. In addition to two or maybe three 120v circuits so I had multiple options on each wall, I put another circuit in the ceiling so I could add lots more light. Still not enough light everywhere I would like, but it is much better than it would have been. Whenever a machine is running the DC is also on.
I did not originally put 220 in so had to have that done later when I upgraded a couple of my machines. Now I Wish I had put in two or three of those as well.
There is another thread running now about 220v extension cords.....
Good luck...

 

[zdorsch]

Do you have a 200 amp sub panel? How far is your main panel from the garage? Do you plan on getting larger tools or welding?

Depending on how far the main panel is, you have open spaces in the box and if you don’t plan on a lot of tools, you may be ahead just running a few 20 amp circuits instead of a sub panel.

I just finished up the sub panel for my garage shop. I went with a 100 amp panel (it wasn’t much more than 60 amp panel). I will also mention #2 copper is not cheap right now.

 

[junquecol]

When I built my shop 40+ years ago, I went witha 60 amp sub panel. Never lacked for power. Have stick welder, 13" & 15" planners, table saw, jointer, DC, band saw, air compressor, metal cutting band saw, plus assorted hand power tools. I used my shop for years, building cabinets for local "Y's." If memeory serve me correct, 60 amps is the minimum for a sub panel

 

[Oka]

Here is what I did on my place. Added a 60 amp subpanel that panel feeds the shop. That and there were already a 20 amp and a 240 circuit already provided plenty.

 

[beloitdavisja]

Whoa! Lots of great info here. Thanks. I'll fill in some questions:

I don't know what machines you have, what you plan to run simultaneously, etc.

I would be running my DC and one other tool at a time, no more than that. As far as machines:

• Delta Table saw (110 only)
• Steel City 1.5hp Dust Collector
• 2 lathes (Nova Galaxi, Rikon Midi)
• 25-50 Drum Sander
• Rikon 14" bandsaw
• 16.5" floor Drill press
• Delta 13" lunchbox planer
• Rigid oscillating spindle/belt sander
• 20 gallon air compressor
• 6" Rigid jointer
• 12" Disc Sander
• Shop vac
• 12" Milwaukee miter saw
• Fisher Scientific Isotemp Lab Oven (kinda like a big toaster oven. Used for doing wood stabilizing curing Cactus Juice resin)
• Assortment of corded handtools, routers, etc.

A few of those can be converted to 220, but I'm not planning on it. I'm squarely in the hobbyist category, and no plans on going pro

Do you have a 200 amp sub panel? How far is your main panel from the garage? Do you plan on getting larger tools or welding?

I do not plan on getting larger tools or taking up welding. All my tools have to be mobile as well since my wife's parking spot (which is non-negotiable!) is in the middle. When I work, I back her car out and then move tools off the wall.

My main panel is outside on the same side of the house as the garage. Straight shot from the main to the garage under the crawlspace is probably 20-25 feet.
I should point out that my main panel is full, and the 100amp subpanel in the house is also full. Electrician can probably make some adjustments there. Some things are unlabeled and others I have to figure out what & where they are.
This is the main panel:

And remember to have the overhead lights on a separate circuit from you machines....you don't want to lose power to a machine and have the lights go out at the same time.

Definitely. The lights are already on a different circuit than the existing outlets. I'll be keeping those intact, but adding an additional circuit for more overhead lights is a good idea. The existing lighting is pretty poor - just two 4' fluorescent fixtures and the garage door opener (which doesn't really count). Plus the light switch for those is in the house. Would be nice to have a light switch *in* the garage.

- bumping to 60A service if you think you may feed a future heater or ac system in the garage.

- go ahead and install a couple of 220V / 20A outlets. Your intentions may not include 220V tools but that could change later plus, if any of your current tools are 115/230v convertible you may choose to switch them over down the road. Convertible tools run better and cooler at the higher voltage.

- install boxes for plenty of lighting in the ceiling.

- install an outlet in the ceiling for a cord reel. That’s proven to work well for me and perhaps would for you too.

I had a cord reel on my xmas list and no one got it for me :-( but that's a good idea. I may have to judge how it is in the summer (we only moved in late September) but so far the recent cold temperatures haven't been bad in there. Door is insulated and there's living space above. I put up a thermometer in there over xmas during the really cold temps and it didn't get below about 55 in there. A mini split AC wouldn't really be an option due to how the garage is oriented, unfortunately. The outdoor unit would have to be in the front of the house. Guaranteed not to fly with the HOA.

---

Side note: Thanks to Duke Energy's Christmas Eve blackouts/power outages, I got to real-world test the Generac house generator that the previous owner had installed. That thing is awesome. Our area was out for 10 hours and we stayed comfortable.

 

[Oka]

Here is what most one man band shop run.
1. Dust collector 10-15 amps/120v or 5-8 amps / 240v
2. The big tool you are using (tablesaw, jointer,etc...) typical same voltage
3. Lighting, fans, filters, misc
Maybe you run a jointer and planer concurrent along with a Dust collector.

This is the real demand on the power supply, everything in there is not run at the same time.

One other comment, running things on 220/240v is not pro, but really a decision to lower the loading on the wire and improving the torque (work power) efficiency. If you can, run 220/240, it is a better smoother power.

 

[jlcrtr]

Presumably the main panel isn’t in the garage and that’s why you need the subpanel.

Good advice from Neal on the core service at the subpanel. In addition you may want to consider;

- bumping to 60A service if you think you may feed a future heater or ac system in the garage.

- go ahead and install a couple of 220V / 20A outlets. Your intentions may not include 220V tools but that could change later plus, if any of your current tools are 115/230v convertible you may choose to switch them over down the road. Convertible tools run better and cooler at the higher voltage.

- install boxes for plenty of lighting in the ceiling.

- install an outlet in the ceiling for a cord reel. That’s proven to work well for me and perhaps would for you too.

Just did all this in my shed that will become my shop.

 

[gator]

Aside from electrical needs, place all your outlets greater than 48" above the floor so you can store sheetgoods against the wall or put a bench anywhere you need.

 

[jlwest]

Go 220v where ever you can. It uses 1/2 the amps compared to 110v. Receptacle's in the ceiling for lighting and power options. The more amps to the subpanel the better.

 

[mkepke]

<snip>
One other comment, running things on 220/240v is not pro, but really a decision to lower the loading on the wire and improving the torque (work power) efficiency. If you can, run 220/240, it is a better smoother power.

Or running things on 240v is for when you decide a lunchbox planer won’t cut it anymore.

Or you find a great deal on 3ph equipment and you need to run a VFD..or two..or three.

That said, if you make sure your electrician installs a large enough sub panel now (I like min 60a) and your walls aren’t closed, you can add 240v circuits later when the need is apparent.

-Mark, hobbyist with 10-ish 240v machines

 

[JimD]

My shop garage is separate from my car garage. Shop is 14x28, car is 20x28. I spill over a bit sometimes. I have two 20 amp 120V circuits in my shop garage and a 15A lighting circuit. I cheated a bit and ran a few outlets on the light circuit - leds use very little. The only heat I have in there is a little space heater I occasionally use when it is really chilly and I want to do some work. I run a box fan some in the summer. It works fine for me. I ran an additional 20 A 120V circuit when I put in the HF "2hp" DC. The electrical box is on the far side of the car garage so I had to take out some drywall to run the circuit. Was not a huge big deal. I could have just as easily brought 220V over but I've been making sawdust for upwards of 50 years now and haven't decided I need 220V yet. So I'm pretty sure I won't miss it in the future either. (I also have a nice little MIG welder that works just fine on 120V).

Lighting is pretty simple. Charts I saw said we need as much as 100 lumens per square foot. Like circuits, I decided that was too much and put in about 50. It works for me but that might get upgraded at some point. I would figure out a light plan and have the electrician put in those boxes where you need them. Doesn't have to be fancy. In my car garage I just have some of those led things that are like one big bulb but the leds are on 4 fold out wings. They go into a bare bulb socket. 4 foot fluorescent fixture equivalents in led are probably better, however. In my shop I have two bulb ceiling fixtures with big led bulbs in them. Anyway, I would spend some time on this. I think a small panel with both hot legs from your box in it so you have 220V available is a good idea. I think there's a good chance you won't but the added cost is minimal and you might. That and 40 versus 60A is just the size and for 220V the number of conductors in the wire. That can easily be figured out. I'd see how much more it costs to overkill it and have 220V and 60A. I'd also ask the electrician how much more he needs to change out your current box or put plenty of spaces in your new box and move some circuits out to it. I hate having no spaces available - but you can put in half height breakers (at least in some areas).

 

[Gofor]

Sounds like some major work: A couple things to consider:

You said both your main and house sub panels are full. So, if you are going to have the main panel replaced, now would be a good time to have the replacement panel include a transfer switch to allow you to hook up an emergency generator. Even though a 30A generator (i.e 5500 kw) may meet your emergency needs, have them run the wire for the generator plug-in capable of carrying 50A in case you want to upgrade later. In that event you will only need to replace the receptacle. Having the transfer switch in the main panel makes it very easy to manage your load during an emergency just by only swithcing on breakers as needed, and eliminates extension cords running over the floor or in through a door or window. Be aware that if replacing the meter panel, you will be without electricity from the time the power company pulls your meter until they come back and replace it. When I had this done, I was able to connect my generator as soon as the electrician had the panel replaced and the plug-in wired to give me power for the 4 hours we waited for them to re-re-install the meter.

The circuits in the garage will have to be in conduit if they are not run behind the sheet rock or paneling. As Rob said, all the wall outlets will have to be GFI protected (various ways to do this. GFI breakers (expensive) or GFI outlet on the first outlet coming from the panel, which if wired correctly (in series) will protect the following outlets on the circuit). That said, your electrician should be following code, as well as getting the required permits, etc.

Instead of running a lot of outlets, you may want to run two circuits to each location, and have an outlet for each at that location. (i.e. two duplex outlets of different colors in the same four square box). That is what I did in my shed/shop, having ivory for one circuit and white for the other. This keeps the cords together if using two 15A tools in the same area.

 

[awldune]

Something else to consider about a 220 circuit -- sometime in the future you may want to charge an electric vehicle, or install air conditioning for the shop.

 

[waitup]

Something else to consider about a 220 circuit -- sometime in the future you may want to charge an electric vehicle, or install air conditioning for the shop.

We built a new house fairly recently and I did 100A sub panel in the garage for this reason.