The Dunedin Gasworks Museum's endangered fitting shop has been stabilised and strengthened, and restoration work will be completed in about two months, organisers say.
An engineering report had previously warned that the heritage-listed brick building, sited near the museum entrance, was "likely to collapse" unless immediate action was taken.
Architectural planning for the restoration and redevelopment project is being undertaken by Ian Butcher Architecture Ltd.
Mr Butcher said that the building's two long brick walls had been brought back into correct alignment, and the structure had been protected by two interior steel portal frames.
The mortar in brickwork had been replaced with fresh mortar, and fresh roof slates were being put in place.
Further exterior plastering work also had to be done, electrical wiring would be added, and large metal-framed windows fitted within brick arches throughout the building, he said.
The gasworks museum has also recently extended its hours, opening from noon to 4pm each Tuesday, as well as operating the same hours on the first and third Sunday of the month.
John Heaven, a Dunedin Gasworks Museum Trust Board member, was "thrilled" with progress on the building, which will serve as a reception and education area for future museum visitors.
"It's going to be a great asset for our city."
