Running Power from a House to a Shed
How do I go about running power from my house out to a shed? Guide for Sizing Electrical Wire for a Shed, Conduit Size and the Depth of the Trench, Calculate Line Loss and Voltage Drop, Installing a Ground Rod.
Sizing Electrical Wire for a Shed
- I’m installing power to my shed a distance away from my house.
- I am going to install a sub panel from my main 200 amp service of the house out to my shed.
- The problem I am having is the 160 foot distance and the wire that will be required.
- Will I need, or is it recommended to have a separate ground rod? and what size wire would be recommended.
- I am thinking a 60amp 240volt panel but could probably go as low as a 30amp 240volt basically the electricity will be used for lights and a garage door opener.
- I would just like to make the sub panels bigger than needed for future expansion.
- What size wire for a 30 amp, 40 amp or 60 amp sub panel with a feed of 160′, and do I need a ground rod?
- Will I need a separate ground or can I carry the one from the house.
This electrical wiring question came from: Steve, from Manassas, Virginia.
Thanks for your electrical wiring question Steve.
How to Install Electrical Power for a Shed
Application: Installing Underground Electric Wiring to a Shed.
Skill Level: Intermediate to Advanced – Best performed by a Licensed Electrician.
Equipment: Depends on the method that will be used to install the electric circuit at each specific location.
Tools Required: Basic Electricians Pouch Hand Tool, Voltage Tester, trenching equipment or shovels .
Estimated Time: Depends on personal level experience and ability to work with tools and the condition of the soil where PVC conduit or direct burial cable will be installed.
Precaution: Identify existing and local circuit or power sources, turn them OFF and Tag it with a Note before working with the trenching process.
Notice: Installing additional electrical wiring for a shed should be done according to local and national electrical codes with a permit and be inspected.
Installing Electrical Power from a House Panel to a Shed
The following is an example of how to install an electrical circuit for a shed.
- Size of the Panel
Determine the amount of power that will be required or the maximum rating of the shed panel. The electrical circuits of the shed panel must be defined which will have impact on the design of the circuit.
- PVC Conduit or Direct Burial
Decide if the circuit will be installed into a PVC conduit or if Direct Burial cable will be used. If the size of the panel may be increased in the future then a larger conduit should be installed to provide ample capacity for the wire conductors.
- Circuit Wire Type
Decide which wire type of wire or cable will be used to use for the panel circuit, and if the conductors will be aluminum or copper. Special attention should be given to the specific circuit that will be connected to the shed panel. If there will be any motor loads then it may be best to install copper wire, or increase the size of the panel to allow for the additional current that is required when motors start. Specific information should be identified for all equipment with electric motors.
- Calculate Line Loss and Voltage Drop
The length of the cable run from the home panel to the shed panel must be factored in to calculate the size of the cable, which will also depend on the type of insulation and if the conductors will be aluminum or copper.
- Conduit Size and the Depth of the Trench
Once the cable size and type have been determined then the specific conduit size may be determined and the depth of the trench. Here is where soil conditions will be a factor because if the required depth of the trench will not be possible then the conduit type will need to be changed to electrical rigid pipe and direct burial cable will not be allowed. Optional exceptions and allowances are provided in some cases such as this where the main panel circuit is protected by a GFCI circuit breaker.
- Ground Rod
A ground rod may be driven at the location of the shed, therefore a ground wire will not be required with the panel circuit from the house panel.
- The Overall Plan for Wiring a Shed
- Consider what the panel will be used for, and any future plans for more equipment and electrical circuits.
- As you can see, there are many items that must be identified before the final circuit is designed.
- Many factors will have an effect on a fully functional and safe circuit for this shed panel.
More about Electrical Wiring for a Shed Panel
- Home Electrical Wiring Codes
Electrical Code Articles for Home Wiring
- Electrical Code Directory covering electrical-grounding, electrical-services, electrical-underground, and electrical-wiring.
- Electrical Codes for Services
- Basic House Wiring Circuits
House Wiring Circuits and Circuit Breakers
- This article looks at common 120 volt and 240 volt house wiring circuits and the circuit breakers that are installed identifying the types and amperage sizes used in most homes.
- Home Electrical Wire
Electrical Wire for the Home
- Complete listing of electrical wire types and parts used for home projects with electrical code information serves as selection guidelines.