Running power to new (attached) garage.

[iwannadie]

I recently bought a house and plan to be there for a while and it currently has just a single 110 outlet in the garage(well one for the door opener on the ceiling too). I have a buddy who is a general contractor and said he will hook me up all at cost so I want to try and figure out a good plan.

The garage is attached and the main breaker for the house is on the oppesite side of the house. My thought was run power to a sub box for the garage then run a pair of 220 outlets for welder and compressor and a few 110 outlets(maybe 3-4) for other stuff. Is that something that makes sense rather than running cable for each outlet all the way from the main breaker for each outlet? Also I know building codes vary alot but would it make sense to keep the garage breaker inside the garage rather than putting it outside? I figure it might be nice having the ability to shut power off at hand.

I'm worried it's going to cost a fortune to run power to my garage .

 

[David_Bricker]

I recently ran, 30 years late, a line from main breaker panel to garage. Like you, the main panel is on the opposite end of the house (75' run). I went overboard, and ran 2/2/2/4 aluminum cable. I'll use a 90 amp breaker in the main panel.

Sub panels are relatively cheap. I got a 24 circuit panel for about $50. Get a big panel, so you'll never do it again.

With long distances, personally, I think you're better off installing a sub panel in the garage. I would put the panel inside, not outside.

David Bricker / SYR

 

[AJPulley]

I recently bought a house and plan to be there for a while and it currently has just a single 110 outlet in the garage(well one for the door opener on the ceiling too). I have a buddy who is a general contractor and said he will hook me up all at cost so I want to try and figure out a good plan.

The garage is attached and the main breaker for the house is on the oppesite side of the house. My thought was run power to a sub box for the garage then run a pair of 220 outlets for welder and compressor and a few 110 outlets(maybe 3-4) for other stuff. Is that something that makes sense rather than running cable for each outlet all the way from the main breaker for each outlet? Also I know building codes vary alot but would it make sense to keep the garage breaker inside the garage rather than putting it outside? I figure it might be nice having the ability to shut power off at hand.

I'm worried it's going to cost a fortune to run power to my garage .

Send me some pictures. I'm a Master Electrician, Electrical Instructor and Alternate Wiring Inspector. Not that any of that means anything other than that is my profession. Perhaps I can give you some suggestions.


Without knowing all the details of your house, yes, that makes sense to run a feeder from your main panel to a sub-panel in the garage. It makes no difference if the sub-panel has a main breaker of its own- your feeder will originate in the main panel with the correct-sized circuit breaker. To get from A to B is solely up to you; it may be less expensive to trench it through the yard, go through the attic, or basement if you have one, crawl space, etc.

 

[RCP Phx]

If you have any questions, pm me. 40yrs IBEW journeyman wireman, 20yrs as senoir electrical inspector for the city of phoenix, and 20yrs IAEI. Ron

 

[RCP Phx]

Questions for you before you get started.......
Who's your AHJ, Gilbert or Mesa?
What size is Service panel?
What brand is your service panel?
Do you have space for a 2-pole breaker?

 

[Bent]

I recently ran, 30 years late, a line from main breaker panel to garage. Like you, the main panel is on the opposite end of the house (75' run). I went overboard, and ran 2/2/2/4 aluminum cable. I'll use a 90 amp breaker in the main panel.

Sub panels are relatively cheap. I got a 24 circuit panel for about $50. Get a big panel, so you'll never do it again.

With long distances, personally, I think you're better off installing a sub panel in the garage. I would put the panel inside, not outside.

David Bricker / SYR

Why not stranded copper?

 

[Anak]

I wonder if folks realize the OP was asking this question 3 years ago. I hope he has taken care of things by now.

As to why Al Vs Cu, generally it is a matter of price. Big copper comes with a big price tag. Aluminum service conductors don't seem to be as problematic as Aluminum branch circuits either. Although, that said, I currently have a claim going with the utility company over a pair of garage door openers and a microwave that died on account of their loose neutral. But I still think that is the exception.

 

[AJPulley]

I wonder if folks realize the OP was asking this question 3 years ago. I hope he has taken care of things by now.

As to why Al Vs Cu, generally it is a matter of price. Big copper comes with a big price tag. Aluminum service conductors don't seem to be as problematic as Aluminum branch circuits either. Although, that said, I currently have a claim going with the utility company over a pair of garage door openers and a microwave that died on account of their loose neutral. But I still think that is the exception.

Well, laugh my ass off upside down. I didn’t notice that! You wouldn’t hold it against me for trying to help someone, would you?

Regarding aluminum conductors... the
AL alloy used in feeder and service conductors work well when treated correctly. The lugs they go into must be rated for such, and an oxide inhibitor is usually applied, though not required by any version of the NEC. But, notice that most manufactures of certain listed wet location connectors pre apply the inhibitor inside their connectors. The conductors need to be protected from damage, even URD triplex in the ground. If a pinhole exposed the alloy to the environment, especially humid and salty areas, the AL converts to oxide, which does not conduct electricity. Conductors aren’t manufactured below a certain size, and hasn’t been used in NM cable is decades. The smaller size wires needed to be deranged a lot, and using regular wire nuts was/is a no-no.

 

[Jeremiah Chaney]

I see. Thanks for the detailed tip, AJ!