Along with the clarifications stated by electure, have you compiled Load Calculations for both the New and Existing Services?

To begin with, I suggest contacting the Local Utility's Service Planner, to discuss this upgrade.
Be sure to have at least a basic Load Calculations Database ready for referencing, too.

If this T.I. Work _DOES NOT_ involve the Service Capacity, then ... ???
(please elaborate)

--Scott (EE)

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!