"We're still not sure what has caused it at this stage," he said. "There's nothing to show it was accidental and we have to look at if it was deliberate."
Mr Kandori, who works for the Whangarei District Council, was grateful his family was unharmed.
He was asleep in the bedroom while his wife and three young children slept in the lounge as it was the warmest room.
"I think that was the saviour really because if they were in their own bedroom ... "
While the lounge was near the front of the house, the children's bedroom was closer to the back of the house.
It took about 30 seconds to get his family outside, he said.
Mr Kandori managed to grab a briefcase with the family's important documents inside and move their car away from the flames.
The parents, along with neighbours and friends, were scouring the remains yesterday for any belongings they could salvage.
The family, who have lived in the house for four years, moved to New Zealand for more opportunities, Mr Kandori said. The children are aged 9, 4 and 2.
"We just have to be positive and think about the future," Mr Kandori said.
After examining the property yesterday morning, Mr Bain had ruled out all accidental causes including electrical fault, embers from a cigarette and discarded fire ashes.
The fire service and police would continue to investigate the cause of the fire, he said.
It may be a matter of days or weeks before it could be determined. Over winter there were often more house fires, Mr Bain said.
"It's time to make sure that your smoke alarms are working and they are tested," he said.
Mr Bain reminded people to discard any ashes from the fireplace in a bucket away from anything that could catch fire like garages.
People should not leave electric blankets on overnight. Early Monday morning, a fire caused by an electrical fault destroyed a home on Ngunguru Rd.