Service to New Garage

[ksmith17]

My home's electric service comes from a pole located approximately 75' from my house. The wires run underground from the pole to a meter mounted on my house. I plan to build a garage on a slab in the vicinity of the pole, between the pole and my house. The current electrical supply will run under the new slab.

My questions are, in order to provide electrical service to my new garage do I need to:

Run underground from my house all the way back to the new garage?

Can I create an underground junction box or splice near my new garage to provide the service thereby shortening the amount of new underground line?

I would have this work done by a licensed electrician.

Thanks,

 

[James-W]

First off, how big is the electrical service to your house? If your house electrical service is 100 amp or less, then I would see about going with a separate electrical service for the garage.

Also, what are you going to be doing in the garage? Will you be using equipment that draws considerable power such as welding?

 

[pattenp]

First thing it helps to know where you live (country/state). Typically you run the feed from the house panel to the garage.

 

[ambenz]

Most likely, the run from the street to that pole on your property isn't large enough to handle a separate meter.
So, you would have to run a separate line from the home breaker box to the garage, just to have 30 amp service in the garage.
You might have to upgrade your service to get another meter on the garage so you can run more than 30 amp service in the garage.
Your least expensive option is going to be running a double pole 30 amp breaker in the house breaker box out to the garage.
Any other option and you are talking thousands of dollars.

 

[ksmith17]

Thanks, to answer your questions:

My house has 200 amp service.
I plan to use this as a woodworking hobby shop. I have several pieces of equipment that run on both 220 single phase and 110
My location is upstate NY near Syracuse.

Thanks,

 

[pattenp]

I'll say with the most confidence that you will need to run a feeder from your house panel to the new garage. The size of feeder depends on the actual anticipated loads you'll have. You need to add up the amps of each item you expect that may be running at the same time and figure the needed supply amps. Heat, A/C, lights, welder, fans, tools, etc. Typically I see that a 50 to 60 amp supply is all that's needed. From my experience 30A is bottom line and I don't recommend going that small.

 

[wyliesdiesels]

Is there a disconnect at the meter?

 

[vavet]

I'll say with the most confidence that you will need to run a feeder from your house panel to the new garage. The size of feeder depends on the actual anticipated loads you'll have. You need to add up the amps of each item you expect that may be running at the same time and figure the needed supply amps. Heat, A/C, lights, welder, fans, tools, etc. Typically I see that a 50 to 60 amp supply is all that's needed. From my experience 30A is bottom line and I don't recommend going that small.

You forgot the 2x factor after adding up everything. That is needed because, well, if some power is good, more power is better.

But seriously, you have to account for the spike when first starting an inductive load (anything with a motor) and you don't want to have to do it again. it's a whole lot easier to size it for 100 amps now than to dig it up later to redo it. If it's only you working in the shop, then maybe you can be more conservative. Maybe you'll only ever have 2 motors running at the same time - a planer and the dust collector, perhaps.

 

[ard]

The current electrical supply will run under the new slab.

Utilities (aka 'the power company") usually will not allow a line ('their line') to run UNDER a slab

As in, you will not be allowed to build the new garage on top of the service line from pole to house. That line will need to be rerouted.

 

[Buckgnarly]

Talk to your local power company. I went with a separate service, increased my electric by zero because the second meter doubled the amount of cheaper electric we get. It's prorated and after the set amount of kilowatts the price triples...my garage actually got us more cheap electric, plus they paid for the aerial wire.
All depends on what the PC does, their billing, how they want you to run it, etc. Separate meter allows you to put a big a service as you want, I went 200....but also did all work myself.
Your electrician and power company are going to give you a much better idea and options than people on the net form all over the country.

 

[Stuart in MN]

If the garage is going to be directly in line between the house and the power pole, you may want to consider running the service to a new 200 amp panel located in the garage, and then feeding the existing panel in the house from there. Your electrician should be able to look at the situation and let you know if this is a good way to go or not.

 

[ard]

There are a good many solutions, depends on your locale- what they require- and also your needs and loads.

One option is to have the meter on the garage with 2 breakers (or disconnects)- one that controls power to a new subpanel inside the garage, the other controls 200A to the existing house service. That line that currently goes from home to pole, is pulled up and routed up into the bottom of this new meter/dual disconnect.

Lots of possibilities

 

[wyliesdiesels]

You forgot the 2x factor after adding up everything. That is needed because, well, if some power is good, more power is better.

But seriously, you have to account for the spike when first starting an inductive load (anything with a motor) and you don't want to have to do it again. it's a whole lot easier to size it for 100 amps now than to dig it up later to redo it. If it's only you working in the shop, then maybe you can be more conservative. Maybe you'll only ever have 2 motors running at the same time - a planer and the dust collector, perhaps.

What on earth are you talking about?

 

[ksmith17]

Thanks everyone for your input. I'm going to call my power company tomorrow and discuss with them.

 

[JamesW84]

Most likely, the run from the street to that pole on your property isn't large enough to handle a separate meter.
So, you would have to run a separate line from the home breaker box to the garage, just to have 30 amp service in the garage.
You might have to upgrade your service to get another meter on the garage so you can run more than 30 amp service in the garage.
Your least expensive option is going to be running a double pole 30 amp breaker in the house breaker box out to the garage.
Any other option and you are talking thousands of dollars.

Curious where the mysterious 30 amp number comes from? Your breakers don't all have to add up to what the panel is rated at because you don't use them all at the same time. You could just turn off something in the house or not use something that uses a lot of power when you need power in the garage or vice versa.

I'm gonna run 90 amps to mine (200 amps at the house). I'd do more, but I'm watching the cost of wire since it will be a long run and I'll have voltage drop.

 

[Bretny]

I have a pole on my property too. Its owned by the power company so im only responsible for giving them a connection point.
In your case i think you have two options if its not your pole. Give them a connection point on the pole and possibly pay a meter/hook up charge every month...or make the new garage a sub pannel off your main pannel.
If you own the pole this may complicate things a bit if its not sized right.

 

[rburke65]

ard.....I don't think the power company owns the "under slab conduit". Power company ownership ends at the pole. The owners ownership starts at the weather head of the service.

 

[ard]

"ownership" and 'what they permit' are two different things.

I had to run my conduit at my expense, but to their specs. Until it get to the meter, they control it.

YMMV based on POCO rules and tariff. As I recall it isnt an NEC issue, more of a poco issue

From my local PG&E service manual:

The applicant shall provide the trench, conduit, and backfill in accordance with Electric Rule 16 and PG&E requirements. PG&E will furnish and install the service cables and make the connection at the point of service
delivery in the applicant’s service termination enclosure.

Qualification of material for use as backfill is the responsibility of the job foreman or, in the case of contract work, the inspector or their designee. A visual inspection of the material is sufficient for evaluation of the material. The source of the backfill, native or import, is immaterial to the suitability of the backfill for use in the trench. In new construction areas, the developer may have a soils report available, which will assist in determining if import backfill is necessary.

9. The conduit type for PG&E’s service conductors, on or under the foundation up to 10’ past the outside wall of the applicant’s building, shall be UL PVC Schedule 40 or 80. Schedule 40 shall not be used in locations where it would be subject to physical damage. To avoid cable insulation damage, the ends of conduits shall be provided with a suitable fitting, such as a bushing, ******, hub, cable protector, or end bell.

Note:
Conduits shall not pass under or through one building to supply adjacent buildings.

Note Bolded...

 

[rooster-tail]

This is how mine is run at my cabin in the country.

 

[tailshaft56]

are you sure you can put a slab over the your entrance feed. I am going to have to move mine for the shop I want to build. now our POCO is the city and everthing is underground in our neighborhood.

 

[Norcal]

If the existing PoCo conductors are direct buried, no building can be placed over them, this is not a PoCo requirement, see NEC article 300.5(C).

 

[ard]

If the existing PoCo conductors are direct buried, no building can be placed over them, this is not a PoCo requirement, see NEC article 300.5(C).

im confused...does the poco wiring (ie 'before the meter') need to be NEC compliant??

 

[Norcal]

im confused...does the poco wiring (ie 'before the meter') need to be NEC compliant??

If they are in a conduit, then it seems to be OK to construct a building over them, direct buried it's not OK.

 

[sleek98]

When I did my house and shop last year, we had to come from the street into the house, do a disconnect in the house for the shop and then run the wire out to the shop. I wanted the disconnect outside and trenched to the shop vs running it through the basement but the city would not allow that. Said it had to go into the residence first. I ended up running 200 amps to the detached since it was only 100 bucks more than 100 amps.

I think they will make you move the current feeder to be out of the way of the new building and then you can run a line out to the detached.

 

[ard]

If they are in a conduit, then it seems to be OK to construct a building over them, direct buried it's not OK.

For NEC, perhaps.

But on the poco side of the meter, only poco rules apply....

 

[Norcal]

Even if it is OK, I would not be comfortable with the idea of building over them..

 

[850xpeps]

Even if it is OK, I would not be comfortable with the idea of building over them..

Why not? If they are in conduit they can be replaced if you have to trench new just go around the building.


Sent from my iPad using Tapatalk Pro

 

[ard]

Why not? If they are in conduit they can be replaced if you have to trench new just go around the building.

IMO- Because the conductors are not over current protected.

(and to be clear, the OP is only about POCO connections PRIOR to the meter...)

 

[wyliesdiesels]

IMO- Because the conductors are not over current protected.

(and to be clear, the OP is only about POCO connections PRIOR to the meter...)

This is a great point!

 

[ard]

This is a great point!

A neighbor had a failure of his line between house and pole. (Meter on house)

There was smoke coming out of cracks in his driveway... poco guys peeled up some of the asphalt while they were waiting on a cherry picker to get up and cut the power, and it was dramatic- ground smoking.

After they cut power, they dug down and patched the wire. Replacing the drive was at his expense.

This is why many Pocos don't want a foundation over their lines...




Three months later his line to the well failed- THAT one was on him.

Both direct bury cable...YMMV. (I knew the contractor that built his place, not unsurprising....)

 

[wyliesdiesels]

A neighbor had a failure of his line between house and pole. (Meter on house)

There was smoke coming out of cracks in his driveway... poco guys peeled up some of the asphalt while they were waiting on a cherry picker to get up and cut the power, and it was dramatic- ground smoking.

After they cut power, they dug down and patched the wire. Replacing the drive was at his expense.

This is why many Pocos don't want a foundation over their lines...


Three months later his line to the well failed- THAT one was on him.

Both direct bury cable...YMMV. (I knew the contractor that built his place, not unsurprising....)

People who forgo the minimal cost of conduit(which is cheap insurance), are penny wise and pound foolish.

Our local PoCo co-op got taken by a slick willy salesman decades ago who sold them miles and miles of direct bury wire that was supposedly a great product. Now years later, the direct buried high voltage primary lines and secondaries from underground residential transformers to the residences are failing left and right.

They are now replacing them as they fail, by putting the new lines in directional bored conduit.

The primary line and secondarys feeding the houses around the corner from me recently started failing. Lineman were out there for several weeks "pot-holing" the street, sidewalks and driveways trying to replace it all. wait a mess....