Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
We purchased a home in June of this year that comes with a 24x32 detached garage. The garage shares power from the 100A panel inside and only has a 14/2 wire running underground to it feeding from a 30A single pole breaker in the box. While this is fine for a garage only being used as storage it doesn't work for my needs to operate a hobby woodworking shop from it.
Currently there are 4 4 ft standard fluorescent shop lights in it, and two motion detected lights on either side of the garage door. There is also a 1/2 HP garage door opener. Each wall has 4 20 amp outlets on them.
When I have the lights on and attempt to turn on my radial arm saw the lights dim severely and the saw struggles to get up to rpm. That immediately triggered me to go figure out what was ran to it.
The 4 lights pull a total of 7 amps and the saw pulls 11.
I need to upgrade the wiring to the garage to support my future needs. Below is what will be in the garage:
Radial Arm Saw - 11 amps - 110v
Delta 10" contractor table saw - 13 amps 110v
14" band saw - 7 amps (Can be wired to 220V and pull 3.5 amps)
6" jointer - 15 amps - 110v
Table top drill press - 8 amp - 110v
Dust collection - 7 amps at 110v, 3.5 amps at 220v
6 LED 4' shop lights - 1.2 amps combined - 110v
Pancake air compressor - 2.6 amps - 110v
Miter Saw - 7 amps - 110v
I will not need to run more than lights, a mini fridge, a small tv, and two pieces of equipment at one time and that would be the dust collector and any one of the tools above. I would like to run two 220v outlets to cover the dust collection and possibly a larger air compressor in the future.
I also have a 50 amp double pole breaker in my panel that isn't currently in use (used to run an outdoor hot tub that was removed) that I wanted to try to utilize if possible and remove the 30A currently in use.
What size wire would be recommended to support my needs (my initial thought was maybe a 10/3) and would the use of that 50A breaker be sufficient to run the load?
1. Stop running your power tools and dimming the lights or you may well burn down your garage or house. That 14/2 is way overloaded and the entire setup is completely outside code and any margin of safety.
2. Depending n the distance from the box to the garage, you may need wire heavier than 10 ga to feed the garage. I think we used 4, but I would have to go back an check. You need to calculate out the load.
3. For what you are describing, I woudl put a 150 amp subpanel in the garage.
4. Those 20 amp outlets need to be on 12 ga wire, not 14 and connected to 20 amp breakers. If they are on 14 ga wire, and 15 amp breakers, your will just blow the breaker a lot, but at least not likely to start a fire.
5. You have some complex wiring issues. Is your hot tub run form the subpanel? Are the tools you intend to use 120V or 240? AC in the workshop? If you do not know how to do the calcs for the size wire and panel you need, either get a good book and make sure you understand it, or hire an electrician at least get someone to give you wire sizes, breaker sizes, etc. You also need to look at how much you put on any one circuit. If you intend heavy power tool usage, you may want a separate circuit for each outlet, or maybe two or three outlets on a circuit.
1. Stop running your power tools and dimming the lights or you may well burn down your garage or house. That 14/2 is way overloaded and the entire setup is completely outside code and any margin of safety.
I haven't used any tools in the garage since that first attempt when I figured out something wasn't right.
Quote:
Originally Posted by Coldjensens
2. Depending n the distance from the box to the garage, you may need wire heavier than 10 ga to feed the garage. I think we used 4, but I would have to go back an check. You need to calculate out the load.
The distance from the box to the garage is 52 ft to the entry point in the garage wall.
Quote:
Originally Posted by Coldjensens
3. For what you are describing, I would put a 150 amp subpanel in the garage.
I am looking at that option as well if I can feed it from my main box. Due to the way the utilities are ran to the house and where the line is buried if I go up in size too large the pool patio will have to be opened up to run a new wire and new conduit. The conduit is 1" conduit so any wire diameter that won't fit through that conduit will present an issue.
Quote:
Originally Posted by Coldjensens
4. Those 20 amp outlets need to be on 12 ga wire, not 14 and connected to 20 amp breakers. If they are on 14 ga wire, and 15 amp breakers, your will just blow the breaker a lot, but at least not likely to start a fire.
The wiring inside the garage is 12 ga. The wire from the breaker to the garage has been replaced. The old wire is under the house and was cut and replaced when the pool patio was poured. Although it was 12 ga wire and not much better before.
Quote:
Originally Posted by Coldjensens
5. You have some complex wiring issues. Is your hot tub run form the subpanel? Are the tools you intend to use 120V or 240? AC in the workshop? If you do not know how to do the calcs for the size wire and panel you need, either get a good book and make sure you understand it, or hire an electrician at least get someone to give you wire sizes, breaker sizes, etc. You also need to look at how much you put on any one circuit. If you intend heavy power tool usage, you may want a separate circuit for each outlet, or maybe two or three outlets on a circuit.
I'll answer these in order.
There is no hot tub any longer. That wire has been removed. It did feed into a sub panel that also runs my pool pump. The pool pump wire now runs from a different 100a breaker in the main box to a subpanel next to the pump. That sub panel runs the pool pump and the light in the pool. It did also run a pool heater but it has been removed. The wiring was moved to a 100a breaker when the heater was added years ago. The other 50a breaker I mentioned using is no longer in use.
No heat nor AC in the workshop. I will run propane heat in the winter and nothing more than a box fan in the summer. The garage is shaded 24/7 and stays fairly cool in the summer. I will also be insulating it.
Tool voltages are listed above, but most everything is 110v with exception to one 220v dust collector. I would like the option to upgrade my air compressor to a 220v 80 gallon unit one day in the future.
I have an electrician friend who is going to come out at some point and go through it all, but is covered up for a while. I will be responsible for buying all the materials and he is going to do the work. I am trying to get an estimate on the materials needed right now so that I know roughly what I can anticipate spending to fix it so that I have that money set aside when he comes out. I want to be ready (or close to ready) to pull the trigger when he gets there.
I am going to have each wall of outlets on its own circuit. I have the tool layout as such where they shouldn't overload each circuit unless someone turned on every tool on the circuit at once. I wanted to add a smaller subpanel with 6 circuits. One circuit for each bank of outlets, one circuit for the ceiling outlets, and two 220v outlets. Even that would be a stretch as each bank won't have more than 20 amps of tools on it at one time. But since I am the only person using the shop (and have kids, so all tool keys are removed when not in use) that shouldn't be an issue.
We purchased a home in June of this year that comes with a 24x32 detached garage.
The garage shares power from the 100A panel inside and only has a 14/2 wire...
While this is fine...
No... it is not "fine" at all. On any level.
You NEED to upgrade with a NEW FEED of adequate size, grounding, etc
and you may end up needing a new feed (200A?) for the whole sevice.
Quote:
What size wire would be recommended to support my needs...
No less than a 30Amp sub panel (10/4 with ground)...
But for the labor involved to do this right
you may as well go big and do the 60Amp (6/4 with ground).
If you really intend to run a wood shop with MULTIPLE power tools running simultaneously...
as well as the dust collection and lighting... a 100A service is MINIMUM.
... to have capacity to expand later for real shop tool use.
You NEED to upgrade with a NEW FEED of adequate size, grounding, etc
and you may end up needing a new feed (200A?) for the whole sevice.
No less than a 30Amp sub panel (10/4 with ground)...
But for the labor involved to do this right
you may as well go big and do the 60Amp (6/4 with ground).
If you really intend to run a wood shop with MULTIPLE power tools running simultaneously...
as well as the dust collection and lighting... a 100A service is MINIMUM.
... to have capacity to expand later for real shop tool use.
A load calculation is called for to be accurate.
I said while it was fine for a storage garage (meaning you need lights and nothing else) it is NOT fine for my needs.
I also said I don't plan on running multiple power tools simultaneously outside of a 7amp dust collector (which I would like to wire for 220v to run 3.5 amps) and one power tool that could run up to 13 amps (my largest tool). Add in less than 2 amps for lights and you are at the capacity of what will be ran out there. I want to err on the side of caution and not push it to the limit, but I will be the only person working in the shop so I also have to be realistic with my budget and expectations as well. If I had unlimited resources I would run a 200A dedicated meter to the garage and rewire the entire thing (which would be absolute overkill) even though I don't have the space to put enough tools in the shop to ever utilize that service.
This isn't a commercial shop nor will it ever be. It is a garage where I occasionally tinker with smaller woodworking projects when time permits.
Due to the way power runs to my property (it comes in on the opposite side of my 1 acre yard and most of my yard is in the front) and then crosses under the house to the main panel on the opposite side of the house from the meter the cost to run a dedicated feed to the garage would be too expensive to accomplish. We also have underground utilities so the entire yard would have to be trenched.
It would also require me busting up the patio surrounding my in ground pool and a large section of my driveway to get the wire out to it. Hence the reason I asked if I can make what I have work with upgrading the wire to a larger wire and using the larger breaker in the main panel inside the house. I do intend to install a subpanel in the garage.
My electrician friend is going to run a load calculation when he gets time to come out. I am merely trying to get an idea of what kind of material I might need to purchase so that I have budget set aside for the work.
I appreciate all the recommendations so keep them coming.
a 14ga service is not fine. On any level.
Aside from likely being illegal... it's unsafe to keep using.
Good. That really is step one.
The biggest cost/bother is about the ground work for the trench
I agree it is unsafe to use. Whether or not it was illegal is outside of my wheel house and at this point there is nothing I can do about it other than to correct it.
That cost can swing wildly either way. If I can upgrade the wiring and use the breaker I already have my cost will be around the $500-$800 mark for materials. He is charging me $100 in labor as a favor assuming he can re-use the conduit and such already there.
If he has to trench and pull a new service the cost of materials and labor will likely climb exponentially into the $1k-$3k range or more depending on what all has to be torn up and redone. At this point that isn't a cost that I can swallow so it would mean leaving the garage as is and unused until down the road when I can afford to have the work performed.
That's been the main point of this thread. I need to get an idea before I waste all of his time as to whether or not the costs are something I can live with right now.
That's been the main point of this thread. I need to get an idea before...
You seem to have a good idea and you're the only one there to know what is what.
Let your $100 favor electrician friend do the load calc and come up with his "prescription"
and once you have that you can calculate what "par" is for YOUR property and needs.
1. Stop running your power tools and dimming the lights or you may well burn down your garage or house. That 14/2 is way overloaded and the entire setup is completely outside code and any margin of safety.
2. Depending n the distance from the box to the garage, you may need wire heavier than 10 ga to feed the garage. I think we used 4, but I would have to go back an check. You need to calculate out the load.
3. For what you are describing, I woudl put a 150 amp subpanel in the garage.
4. Those 20 amp outlets need to be on 12 ga wire, not 14 and connected to 20 amp breakers. If they are on 14 ga wire, and 15 amp breakers, your will just blow the breaker a lot, but at least not likely to start a fire.
5. You have some complex wiring issues. Is your hot tub run form the subpanel? Are the tools you intend to use 120V or 240? AC in the workshop? If you do not know how to do the calcs for the size wire and panel you need, either get a good book and make sure you understand it, or hire an electrician at least get someone to give you wire sizes, breaker sizes, etc. You also need to look at how much you put on any one circuit. If you intend heavy power tool usage, you may want a separate circuit for each outlet, or maybe two or three outlets on a circuit.
Nope perfectly fine and code compliant to use 20 amp outlets on 14ga wire. You can also use 15 amp outlets on 12ga wire. Please do not comment on things if you don't have the knowledge or experience.
To the OP here is some advice coming from a real electrician. First let me say whoever put a 30 amp breaker on the 14ga circuit that needs to be changed right away to a 15 amp breaker. Second it's perfectly legal to run one branch circuit to a detached garage so what you have is legal. If you are going to be running multiple circuits in the garage then a feeder has to be run. Based on your needs you can go as small as 30 amps with a 10-3 feeder. You are not going to have power tools running at the same time. So buy a 60 amp sub panel and 10-3 UF if you want to cheap out. Or do it the right way with 3/4 pvc with #10 THWN.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
