STAFF at Norfolk County Hall in Norwich expect to return at Easter to the wing they were evacuated from 18 months ago.
Contractors have shored up the damaged structure with a steel support frame.
Around 150 of the county's employees had to move out after structural movement and damage was discovered in the three storey south wing.
Some £900,000 of repair work has since been needed to stabilise the building.
Contractor May Gurney has been working to install the steel frame within the building's existing concrete frame.
The frame solution was devised in conjunction with structural engineer Hale Allen Jones.
Structural movement was discovered two years ago and eventually became serious enough to require evacuation.
Installation of the structural steel has been relatively slow because the building suffers from noise transmission effects, meaning most of the work has been done at night.
Internal access is also difficult. But May Gurney is nevertheless four weeks ahead of schedule.
The original buildings date from the early 1960s and had suffered normal wear and tear.