The Chief Secretary’s Building (CSB), a significant heritage sandstone public building designed by Colonial Architect James Barnet, was built in 1880. The building was initially constructed as “a new and worthy building for the office of Chief Secretary of the Colony as well as providing offices for the Public Works Department”.
The Government Architect’s Office provided specialist-engineering services to enable the adaptive reuse of the Chief Secretary’s Building.
Working on a heritage structure is always challenging; innovations provide a way forward to induct new procedures, compliance mechanisms in an old fabric which fundamentally belongs to another era.
There were new services to be introduced air conditioning, modern day lighting, hydraulic services. Besides, there were structural issues related to the existing building of stabilising the façade and even to rectify a major movement in an entrance arch.
Finite element analysis determined the extent of the problem in the arch. The final solution was made highly visible in an honest admission that interference with original fabric was structurally necessary.
For structural engineering works the challenge was to comply with current Australian Standards, among them, certification against earthquake loads. The building walls, balustrades and architectural ornamentations had to be stabilised.
The building had a combined sewer and stormwater service, which had to be separated. New hydraulic services were required next to the rear wall whose footings were formed in a strata which could easily undermine. Varying the trench width to keep away from zones of influence of the existing footings achieved the solution.
The engineering team exhibited best practice in the selection and installation of building engineering systems so that all work had minimum effect on the fabric of the building while still providing a comfortable and appropriate internal environment for the functions of the Court, Industrial Relations Commission and the Governor of NSW.