Apple has been forced to replace the glass facade of its Sydney CBD store after it was vandalised by a projectile. 

The repair job is rumoured to have cost the IT giant up to $1 million dollars, as construction firm Kell & Rigby's initial attempts to replace the glass sheet were foiled by a faulty construction vehicle.

According to the Sydney Morning Herald, the 13m high, 3m wide and four inch thick panel was damaged last month, however, the replacement glass sheet needed to be imported to Sydney by sea from Germany and placed put in position using proprietry installation technology.

The operation was carried out at midnight, to prevent interuption of city traffic and to cater to public safety.

Speculation is rife on what caused the damage to the window, with some sources suggesting the "small projectile" was a ball bearing, and others that a ball bearing was shot at the glass. The panel was said to be sporting a crack from top to bottom before it was covered.