Firefighters said Nita Notman, of Portobello, would have died if Richard Trotter had not stopped to assist her on November 10, 2010.
Mr Trotter was driving home in the early evening when he saw smoke coming from Mrs Notman's house and stopped to investigate.
At the rear of the house, he saw flames rolling over the kitchen ceiling, the room well ablaze.
He called the Fire Service and called out to see if anyone was inside. He heard no response, so went into the house and started crawling through it looking for any occupants. It was hard to see, but he found Mrs Notman, who was in her mid-80s, had poor sight and used a walker, on the floor in the lounge, where she had fallen after hitting her head on a door while trying to get out of the building.
Mr Trotter held her under her arms and dragged her until she was near a door, where he got her to her feet and outside.
His award citation said the Fire Service said the house was well alight when they arrived, and the fire was fast moving and very intense. It was their opinion that had Mr Trotter not acted as he did, it was unlikely Mrs Notman would have survived.
Mrs Notman was not able to attend the afternoon tea at the Otaru Room in the Civic Centre in Dunedin, at which Governor-General Sir Jerry Mateparae presented Mr Trotter with his medal and citation, but her daughter, Robyn Notman, said her mother and the rest of her family were "extremely grateful" to Mr Trotter.
Many people would have just kept driving, Ms Notman said.
"It's amazing that he had the presence of mind to go and look and take the action that he did."
The bravest people were often just quiet about the things they had done, she said.
Mr Trotter was no exception.
He told the Otago Daily Times he had gone into the house because that was just the sort of thing he was brought up to do.
He did not dwell on that night, and had met Mrs Notman, whom he called "a nice woman", briefly since then.
"I was just on my way home," the hospital orderly said.
It was nice to receive the award and medal, and nice to meet the Governor-General.
Sir Jerry said Mr Trotter's citation provided a glimpse of what must have been a terrifying ordeal.
Mr Trotter could have waited on the Fire Service to arrive, yet he chose to go into Mrs Notman's house.
That action was the legacy he shared with others who had received the society's awards since its inception in 1898, he said.
The silver bravery medal is the society's second-highest honour, after the gold bravery medal, and is awarded in various cases, including where the rescuer is at personal risk when rescuing or attempting to rescue a person whose life may be endangered by fire.