The City Hall and former Supreme Court buildings are set to be restored for $530 million.

Construction work will start in January 2011 and is due for completion by the second half of 2014.

Upon completion, the two landmarks in the Civic District will feature three more basements and will house the 60,000 sq m National Art Gallery, Singapore, which is conceptualised as an exhibition space for temporary and permanent galleries of local and international art.

“The Gallery will be the largest museum in Singapore, and will help to position Singapore as a regional and international hub for visual arts,” said Michael Koh, chief executive of the National Art Gallery, Singapore.

Takenaka-Singapore Piling Joint Venture has been appointed as the main construction contractor after it clinched the $413.8 million contract from the National Heritage Board.

The major challenge of the construction will be the preservation of the two 80-year-old national monuments, with other challenges including poor soil conditions and the need for better security due to its prime location.

“We look forward to preserving and at the same time, reinventing these iconic buildings,” said Masaru Chayama, general manager of Takenaka Corporation, Singapore, which co-owns the JV, together with Singapore Piling & Civil Engineering Private Limited, a wholly-owned subsidiary of BBR Holdings.

“We are truly excited to be involved in such a prestigious project in the local arts scene and we look forward to working with Takenaka Corporation over the coming months,” said Andrew Tan, chief executive of BBR Group.

The gallery is due to open progressively from the end of 2014 onwards.