The 800-bed Extension Block at a cost of HK$1.65B is due for completion by end-2009. It is also the teaching hospital for the Medical School of the Chinese University of Hong Kong. This is the first stage in the re-provision of the existing hospital built in the 70's. The building site is the former open air carpark and helipad at the north-west corner of the complex facing the bus terminus and the Ma On Shan Rail line.

The Extension Block is 13-storey tall with a total construction area of about 86,000 s.m.. The upper floors consist of three nursing units (wards) clustered around a central vertical stair and lift core. This provides maximum light and air to the wards while having shortest walking distances and facilitates east wayfinding. The podium floors house the diagnostic and treatment departments including two floors of operating theatres, intensive care unit, burns unit and the district accident and emergency department on the ground floor.

External treatment of the Extension Block emphasize the vertical elements of the tower by bringing them directly to ground level. The bulky podium volumes are reduced by horizontal window treatment and articulation. The main entrances are given special treatment to welcome visitors with glazed canopies and glassed-in double volume.

Foundation work is proceeding on site with the first floors of the superstructure schedule to be cast in early 2008.