A 16-year-old from Kerikeri had been referred to Police Youth Aid.
Tenant Roger Harper said the house was fine when he went into town about 4pm. His son and grandson, who share the MacMurray Road home, were also out.
"Then one of my nieces came downtown and said, 'I think your home is on fire'."
He had only been able to watch, comforted by friends, as firefighters battled to save what they could. It wasn't much.
The "small-time, self-employed painter/decorator" said his power tools, scaffolding and paint were uninsured, and had probably been destroyed, but worse than that was losing family photos and artwork by his six children.
"A lot of it is irreplaceable ... all their teddies, their drawings - my bedroom was covered in their drawings," he said.
The alarm was raised by staff at a backpackers' lodge across the road and a pair of travellers flatting next door. Englishman Mike Hall and Welshman Ryan Williams were celebrating a successful skydive with a beer on their lawn when they heard glass shattering.
When they looked next door they saw smoke and flames billowing from the far end of the house. They called 111, and the first fire appliance arrived two or three minutes later.
"Me and the guys piled over to see if anybody was home," Mr Williams said.
"There's heaps of little kids there in the summer. A lady shouted at us to get out of it, because there was no one inside."
As the fire spread to the other side of the house, close to their flat, they gathered their passports and laptops just in case.
