Firefighters were alerted to the inferno at Pukeuri around 3:50 am, according to a spokesperson from Fire and Emergency New Zealand.
A total of six fire trucks rushed to the scene, with the initial responders discovering the residence completely ablaze.
The flames were finally extinguished by 6:15 am.
Oamaru Sergeant Tony Woodbridge stated that the cause of the fire remains unknown at this time.
An investigation is currently underway by a fire specialist on the premises.
The property had been vacant for quite some time, added Sgt Woodbridge.
He urged anyone who may have witnessed anything suspicious in the vicinity to contact the authorities.