Bevan Gobbett, of Clonbinane, huddled in the bunker with his wife and six-year-old daughter as fire destroyed their home and two cars. "If we didn't have it, I don't doubt that we would be dead," he said yesterday.

He described the experience as a terrifying six or so hours, with the fire roaring like a jet engine outside and smoke filling the container. "It wasn't a pleasant experience being in there."

Mr Gobbett said the bunker came with the property when he bought it about eight years ago. "It is a 20-foot shipping container buried in the ground behind the brick wall. It has an air vent up on the top so it can breathe."

The Gobbetts modified it slightly and equipped it with respirators, water, fire extinguishers and warm blankets.

Mr Gobbett had been a CFA firefighter and said he had always believed his property was defendable. The land was clear of trees for at least 30 metres around the house, and he had bought fire hoses, water pumps and a sprinkler system.

He did not consider the declaration of a total fire ban day to be a trigger for evacuation: "If you bailed out every time there was a forecast of a total fire ban or a bad fire day, you would probably spend half the summer not at home."

Mr Gobbett said that on the day he was priming water pumps when his wife pointed at the sky and said: "What's that?"

"It was a ball of fire … heading straight towards the house, coming straight up the valley."

Then balls of fire began dropping around him. He raced to the back shed and realised a second fire front was coming. Then he ran to the bunker and joined his wife and child inside.

They remained there until midnight because it was too hot to come out.

"You could have put a hundred fire tankers and Elvis (the water-bombing helicopter) in front of my house that day and you would have killed a hundred fire tankers and Elvis."