It is understood he suffered from smoke inhalation and was the sole occupant of the house.
A neighbour in the rear house, who did not want to be named, said they were alerted to the blaze when a passerby knocked on their door and said “Get out! Your house is on fire”.
“He came and belted on our door.”
The neighbour commended the passer-by, named Leo, for helping them and alerting them to the blaze.
The neighbour said the man who lived in the front house had managed to escape and appeared okay, when they evacuated.
The neighbour said firefighters were on the scene quickly and “there was a lot of smoke”.
The neighbours were relieved the fire did not spread to their home and said the incident “was pretty scary”.
They remained without power and water on Monday morning.
A Fire and Emergency NZ (FENZ) spokeswoman said two fire trucks attended from Hastings Fire Station, and the fire was “well involved” upon arrival.
Firefighters remained at the scene until shortly after 10am.
A fire investigator has since visited the home, and the FENZ spokeswoman said the cause was “undetermined” at this stage.
The house was severely damaged and broken windows have since been boarded up.
Police were notified but are not investigating.