A number of firefighters are at the scene on Tawariki St, with crews using an aerial crane to try contain the fire.
Jeremy Lodder was working at a construction site nearby when he noticed a fire on the other side of the road.
"I just thought it was a burn-off, but it was a strange place for it in the middle of the city. I realised it was pretty close to the brick walls and once I saw that, I stopped my machine that I was using, told the other boys to stop, talked to the supervisor who was here [and] told him to call the fire brigade," Lodder said.
"... knocked on the doors, found one guy in there, got him out, while the house was on fire."
Lodder said he's seen house fires before and knows how fast they can spread.
"That's why as soon as I saw it I jumped out [and] stopped my gear."
Fire and Emergency New Zealand (Fenz) Senior Station Officer Michael Manning told RNZ there were multiple calls just after 10am.
"We got here within a couple of minutes and the rear of the house was well involved in fire and the neighbouring house was also starting to catch fire," he said.
He said the first home has extensive damage, but the neighbour's home has been spared and has only scorch marks.
"The crews did an excellent job stopping the fire moving through that property," he said.
"He's now been located and is speaking with our fire investigators and police," Manning said.
Six fire trucks and more than 20 crew were called in.
Manning said it had been a busy morning for Auckland fire crews. They responded to the Ponsonby fire fresh after attending a fire on Hobson St in the CBD.
"We had just recommissioned from that when this job came in," he said.
Crews are using a high-reach ladder truck from Wellington to take the roof off and put out the remaining pockets of fire," Manning said.
The fire comes a day after a person died in another house fire in Auckland.
