Dedicated line for outbuilding?

[mjc1925]

Looking to replace a damaged underground cable feeding a small outbuilding. Is a dedicated line from the panel required ?

Current setup when I purchased the house: The cable feeding the outbuilding (about 10 feet from the house) shares a circuit with a ceiling fan and two lights in the house. The outbuilding now has two outlets and two lights on pull chains.

If a dedicated line is the way to go, there's no room in my panel for a new breaker. There is an outlet coming off the panel with nothing else on the circuit. Could I use that to extend a new line?

 

[jpalatine]

I would change the duplex outlet on the unused circuit to GFI then use that to run to the outbuilding. That way you would be protected from being electrocuted from an outside line.