The house was completely destroyed and police were at the scene throughout Thursday to determine the cause.

The 000 call came through at about 6.43pm and the house was about 60 per cent involved in fire by the time firefighters arrived, NSW Rural Fire Service Southern Tablelands Zone Operations Officer Lachlan Gilchrist said.

Big Hill, Marulan, Towrang and Goulburn Support Rural Fire Brigades were in attendance.

"Crews stayed most of the evening doing what they could but there was a total loss in the end," Mr Gilchrist said.

"Our crews handed it over to police fire investigators this morning at a bit after 8am."

A cause is yet to be determined and the fire would be treated as suspicious until then, Detective Chief Inspector Brendan Bernie of Goulburn Police Station.

"We've had our investigators out there today but we're still at a very early stage with our inquiries," DCI Bernie said.

"No persons were injured."

The occupants of the house are yet to be named, however, Big Hill Rural Fire Brigade Captain Marshall Bass said all emergency services had been extremely supportive towards the family and would continue to support them for as long as needed.

Due to the extent of damage to the house from the fire a report will be prepared for the coroner, DCI Bernie said.

"Anyone with information can contact us," he said.