The cause of a fire that extensively damaged an Ōwhata home in Rotorua overnight is yet to be determined.

Fire and Emergency New Zealand (Fenz) Rotorua senior station officer Gary Balment said two fire crews from the Rotorua station attended the blaze reported just after 8pm on Saturday.

Balment said the single-storey home was “well-involved” when firefighters arrived at the Sunrise Ave property.

“The occupants of the family home were not at home and it was the smoke alarms going off that alerted their neighbours.”

He said the cause of the blaze, which torched an estimated 80 per cent of the home, was yet to be determined but the fire was not being treated as suspicious.

Balment, who did not attend the fire himself, said he understood there was extensive damage to the kitchen, lounge and some of the bedrooms.

A fire investigator was working to establish the cause of the fire, he said.

More to come.