WHEN it was finished in 1978, the 67-storey MLC Centre in Martin Place was not only Australia’s tallest office building, but also the biggest reinforced concrete structure in the world.
Thirty-three years later, the Harry Seidler-designed structure is showing its age. Its concrete facade is breaking up and the owners have agreed to spend $100 million repairing it in an operation that will go 24 hours a day, seven days a week for much of the next four years.
Documents filed by the owners with the Central Sydney Planning Committee show what a massive repair job it will be to stabilize the remaining solid parts of the modernist facade and repair those that are not.
It will take 10 months just to finish preliminary works.
Then workers on 12-hour shifts will blast away damaged concrete with dry ice and grit, and use small jackhammers and angle grinders to prepare the surfaces for filling and patching.
They will also drill thousands of 100 millimeter-deep holes into which anodes will be inserted, which should help preserve the facade panels for the next 40 years.
This main stage of the process will last more than two years. To minimize disruption to tenants, the owners have decided the noisiest work will begin at 7pm and go all night, a decision that has angered neighboring residents who have objected to the plans.
The owners, GPT Group and QIC Real Estate, will import insulated French working platforms designed to fit the shape of the building, which they say will reduce the noise of the jackhammers and other equipment.
The owners blame the deteriorating facade on ”the manner in which pre-cast panels were originally manufactured”.