Mendip District Council is considering moving offices after a council cabinet meeting approved the plan in principle.
The current offices in Cannards Grave Road, Shepton Mallet, need repairs.
Council leader Ken Maddock said: "We have staff in a temporary building, which is just not acceptable in the long-term."
The offices were not energy efficient, failed to meet Disability Discrimination Act guidelines and cannot be adapted, said Mr Maddock.
'Undoubtedly damaged'
He stressed the council was not looking for bigger offices, just "more efficient" ones.
The council currently employs 213 staff at the site, while Capita, which handles council tax and benefits, employs 70 staff.
"If we don't address these issues now the efficiency and effectiveness of our staff, and therefore our service delivery, will undoubtedly be damaged," said Mr Maddock.
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