Two volunteer fire crews — one each from Arrowtown and Frankton — were alerted to the fire in Criterion St about 12.30pm, the first arriving within minutes of the call to emergency services.
Theresa Ayers told the Otago Daily Times she was at home when a passer-by ran down her driveway just before 12.30pm alerting her and her friend, Jackie Melgren, to smoke pouring from the roof of the next-door neighbour’s property.
Mrs Ayers said she called 111 "right away" before attempting to see if anyone, including the couple’s child, understood to be 8 months old, was home.
"That was the thing I was concerned about."
Mrs Melgren said the pair ran to check the house, but realised neither of the couple’s vehicles were there and made a hasty retreat.
"We heard popping and thought ‘it could go at any time’," Mrs Melgren said.
"The fire brigade were here just like that."
The crews, equipped with breathing apparatus, appeared to have brought the fire largely under control within about half an hour.
Sections of the roof were removed and hoses lowered to fight it internally.
However, the damage was extensive, Arrowtown Chief Fire Officer Murray Forward said.
"When we arrived [it was] fully involved ... [They were] just lucky [they had] good smoke alarms; they were working.
"Three out of the four rooms would be a write-off ... [There’s] smoke and water and fire damage."
While he believed he knew where the fire started, the matter had been passed on to fire investigators, he said.
Mrs Ayers said that the young couple, who rented the property, had been living in the weatherboard home for only a couple of months.
It is the second time a property on the site has been involved in a fire.
About 12 years ago, a house on the same section "burnt down" and was subsequently demolished — the house involved in yesterday’s fire was later relocated from Manse Rd to the address, Mrs Ayers said.
