Minor electrical changes generally do not need a permit, but each jurisdiction varies. In some areas, permitting is required for any type of Electrical work, no matter the size in scope or significance. This work however, would by no means ever be considered "minor".


When you meet with the building code representative, ask about the inspection schedule so you know when to call for a rough inspection as well as a final inspection. Many localities have part time inspectors, so if you're on a schedule you should discuss it with them first.;
, You will need light to work on your project after you shut off the electrical power to the building.
 If space is an issue, you don't need to install it next to the main panel. However, you must be able run wire through to that area. Keep in mind that a closet is not an acceptable location for a panel. The area 3 feet (0.9 m) in front of and above and below the the panel should be clear from the floor to the ceiling.


If you install your sub panel closer to the rooms you are adding power to, you will use more of the larger sub-feed cable between the two panels; but fewer smaller wires to the outlets than if you installed the sub panel close to the main panel.

Check with your city's building and codes department to see if you need to acquire a permit before you begin the work.
Find a good light source that can run off a battery or generator.
Determine where you will mount the sub panel.
Shut off your main power breaker before beginning any actual electrical work.
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