Running electrical to a out building

J Bar L

Hello,
I am running electrical to a out building from my Three bay shop. The shop electrical breaker box has been set up for 220. I was wondering what type of wire to run from my shop breaker box to the breaker box in out building? I have a 20X24 ft out building that I am turning into a class room/ office and needing electricity. My next question is the breaker box in out building to get where I can have a couple of 220 breakers Where would I put the wires to main feed in box? I will be adding another 10x24 to this building for a rest room with washer and dryer hot water heater and shower and toilet and vanity. and office area will have a 110 window unit and a electric heater. The classroom Will have a 110 window unit and a computer a projector and 2 ceiling fans with light fixtures. I have wired the outlets to the breaker box with the window unit outlet on it's own circuit. its about 50 feet from my shop to out building what type of wire is needed to run from breaker box to breaker box? Thanks look forward to your answers.

AllanJ

I would run three (changed to) #2 copper or #O aluminum (red or black, black, white) and one #8 copper (green for ground). Use wet location wireing e.g. THWN in conduit buried 18 inches deep.

Alternative, #2-3 (O-3 aluminum) with ground copper direct burial Romex type cable buried 24 inches deep.

Put a double wide 240 volt 100 amp branch circuit breaker in the shop panel to connect the outbuilding feed to. Have a 100 amp (or greater) 120/240 volt breaker box as a subpanel (neutrals and grounds on separater terminal strips) in the outbuilding.

Either the subpanel in the outbuilding needs a master disconnect switch or breaker up top for the incoming feed or you need a separate box next to it with heavy duty (here 100 amp) double pole switch for a master disconnect. This is in addition to the (100 amp) breaker unit in the shop building panel.

Run a #6 copper wire from the outbuilding subpanel ground bus (terminal strip) to a pair of 8' ground rods at least 6 feet apart.

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The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.

J Bar L

Allen,

In the box at shop I have a 240 volt double breaker that I am currently using for the clothes dryer. I am going to move dryer into the out building could I put my 2-3 direct burial romex to that breaker and run it to out building or would I need to have a 100 amp breaker. thanks for the info I wrote all of it down so I can go get the stuff I need.

AllanJ

The panel in the shop should have had a top breaker sized for the wires feeding it. If this is the main panel for the entire premises it would probably be rated at 150 amps or more.

You can temporarily run the #2 gauge wires up from the outbuilding to a breaker somewhat less than 100 amps in the shop panel. You may need some adapters so the fat #2 wires can be connected to smaller breaker terminals.

The need for 100 amps down in the outbuilding is to handle the hot water tank and baseboard heaters. If you can use natural gas or propane for these items then less power would be needed and thinner wires can be run from the shop to the outbuilding.

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The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.

jimmy21

With the equipment you are talking about, you may be able to scoot by with 60 amps by I would recommend going to 100 amps

J Bar L

Ok Well after reading above post which I thank for the replies. I am going to have a ceramic tube electric space heater heating the building. I have 2 110 window A/C units that are wired one separate breakers 1 breaker for each unit. I will have a dryer and hot water heater in bathroom. I will buy a 50 amp double pole breaker for dryer and 30 amp double pole breaker for hot water heater. I have wired the Lights in classroom portion on one circuit. the outlets which is 4 on one circuit and the office will have 5 outlets and one light switch and fixture. and bathroom will have 4 110 outlets and light fixture on that circuit. and ofcourse the dryer and hot water heater will be on their separate circuits. I looked up this wire called Triplex outdoor wire that is aluminum to run from shop to out building. I am trying to figure out if I could put either a 100 amp or 60 amp breaker in the box in the shop to run to out building. But keep in mind this class room is a firearms training class so everything will not be on at one time. I just need to have a restroom for the public use. But also during holiday times we will use it as a guest room as well. Sorry but I am not a electrician But with the money problems I am in I can not afford to hire a electrician at this time.

jimmy21

With all that, i would run a 100 amp circuit.