The art deco Grade II listed building is above Leeds train station, next to the Queens Hotel and fronting City Square.
The 拢9m refurbishment will preserve the character of the building, Network Rail said, while creating more than 30,000 square feet of office accommodation over the ground and six upper floors. It will also create a new entrance within the northern concourse of the station.
Enabling works have already been completed, and the full refurbishment will start next month, with a completion date of autumn 2013.
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