The Treasury Building, Whitehall was built in 1845 to the designs of William Kent, Sir John Soane and Sir Charles Barry. Portland stone was used in the construction of the facades to this Grade II listed building.

Major refurbishment involved careful cleaning, conservation and repair of the Portland Stone forming the external cladding.

Many of the facades of the seventeen courtyards and light wells were adapted to suit the requirements of modern offices. Works involved forming numerous new openings using purpose made glazed bricks and natural Portland Stone. Care was taken to ensure that new work blended seamlessly with the original.

The internal terrazzo, marble floors and marble staircases were cleaned and restored to their former glory repairing the scars and damage from previous adaptations to the building.