Running service to subpanel in adjacent building

[toby267]

Hello,

I plan to run a 100 amp service to my new woodshop building. I will come out of a 200 amp panel in my existing 24x36 garage, run the 36 foot length of that building and on another 3 feet to the wall of the new building. Once at that new building, I need to go about 14 feet to the center of the new wall where the subpanel will be.

My question is, which would be better:

1) to run the service cable underground and in a more direct path to under the new panel,

2) take service cable up into the attic space of the existing building (a 12 foot ceiling) and bridge between the 2 buildings, or

3) bridge across attic as in (2), but come down the outsidie wall of the existing building with conduit then underground to the new wall, then conduit up the wall to behind the new panel

If I go the aerial route, does the service cable need to be in some type of conduit between buildings (it will be about 10 feet in the air)?

Thanks in advance for your opinions.

Toby

 

[Mustang51js]

So two buildings are connected. I would run service cable through attic then. If you do dig then have to use pipe and can't bury the service cable

 

[nehog]

... another 3 feet to the wall of the new building. ...

So two buildings are connected...

Did I miss something? I think he is saying there is three feet between the two buildings.

Toby: I'd go underground, cleaner and more protected.

 

[pattenp]

For ease and less work I'd be inclined to install a piece of metal rigid conduct up in the air between the two buildings since it's only 3ft. Then just run one continuous piece of SER cable.

 

[wyliesdiesels]

For ease and less work I'd be inclined to install a piece of metal rigid conduct up in the air between the two buildings since it's only 3ft. Then just run one continuous piece of SER cable.

Prob the easiest route.

Dont forget grounding electrides and to isolate the neutral bar.

 

[Pwrgeek]

I'm in the middle of basically the same install (actually scarily close). I went underground pipe as I didn't want the unsightly (WAF is a big concern here) wire / conduit bridge between the two buildings. If you haven't already poured the slab for the new building you can also come up inside and save yourself a wall penetration.


Sent from my iPhone using Tapatalk

 

[theoldwizard1]

To the OP, be careful on what type of cable you are using. MHF is commonly used in these setups, but it must be in conduit when used inside of a building. You would have to drop down to 90A also.

On that last note, how much power do you REALLY need ? 60A is pretty common for most 1 man workshops with plenty to spare. "Right sizing" will save a lot of $$$ even on this relatively short run.

 

[toby267]

Thanks for the replies, everyone. As far as load goes ,we will be heating and cooling 1300 sq ft, with woodworking machines downstairs and music amps upstairs, so I think 100 amps is wise.