The project is the first phase of a $2million quake-strengthening project at the school that includes work on the ground-floor rooms of the main boarding house.
He said work in the downstairs area of the boarding house, home for 95 students, will focus on the kitchens, dining room, three common rooms and some dormitories.
The work would take 12 months to complete and start next year, he said.
Quake safety work had been completed at the school in the 1990s, he said, and the second storey of the main boarding house had been strengthened each time the interior of the building was refurbished. He said the quake strengthening would be invisible and other original features of the 1920s building, which includes ornate plaster ceilings and exposed native timber beams and woodwork, would be returned to their former glory.