Fire and police investigators were on the scene on Thursday and it was expected to be some time before the cause was confirmed, Mr Gardiner said.
According to comments on the Wanganui Chronicle Facebook page, the owner of the property now lives in a rest home and the house was being done up by family members so it could be sold.
On Wednesday morning a working smoke alarm and an alert neighbour saved a fire in a house in Paterson St, Aramoho, from spreading.
"The fire was picked up by a neighbour hearing a smoke alarm which saved the house," Mr Gardiner said.
"It meant we were able contain the fire to the laundry area. It goes to show the importance of having a working smoke alarm to alert you or your neighbours to a fire."
Mr Gardiner said the fire was not suspicious.
On Wednesday evening fire crews were called to what was thought to be a building fire in Liffiton St. However, they found that the smoke was caused by people doing burnouts in a warehouse.
A call to the surgical ward at Whanganui Hospital on Wednesday night initially had crews worried, Mr Gardiner said.
"Smoke was entering the building which was a concern with all the electrical equipment there. We worked with local electricians and were able to eliminate possible causes."
A faulty airconditioning unit was found to be the cause of the smoke.
Mr Gardiner said crews had also been busy with vegetation fires, with the tinder dry conditions fuelling scrub and grass fires around the region.