A toddler revived by firefighters after being pulled from his burning home is fighting for his life in Middlemore Hospital.
Housing New Zealand has confirmed that when it last inspected the toddler's family home, all smoke alarms were functioning.
Why the alarms did not alert the family to the fire earlier is under investigation.
The 18-month-old was unresponsive when firefighters rescued him from the house in Malone Rd, Mt Wellington, on Saturday morning.
Adult relatives managed to help two other young children out of a second-storey window as the inferno ripped through the house, but the smoke became too intense and they had to abandon the rescue, leaving the little boy trapped inside.
Neighbours rushed to help, dragging an unconscious man from a downstairs bedroom.
Part of the Fire Service's investigation into the cause of the fire would be around smoke alarms.
"We last inspected the property in June this year and at that time smoke alarm batteries were replaced and a unit refitted," HNZ spokesman Gez Johns said. "All smoke alarms were tested and working."
Mr Johns said as part of the annual tenant inspection, HNZ tested fire alarms at its properties, replacing batteries and/or units if required.
It is not a legal requirement for private landlords to install smoke alarms inside rental properties. But Fire Service fire investigation and arson reduction manager Peter Wilding is pushing for that to change. He is writing a paper which calls for changes to the Tenancy Act, making it compulsory for rental properties to have smoke alarms installed and maintained.
Building and Housing Minister Nick Smith said he was "more favourably disposed" to landlords being responsible for providing smoke alarms but tenants being responsible for their maintenance.
The Mt Wellington fire came just a week after three people were killed in a blaze that destroyed a Hamilton house. Jake Lindsey Hayes, 19, Connor James Swetman, 17, and Maree Johnston, 23, died in the fire at the rented home.
A week earlier 3-year-old O'rlandau Kingi-Day died in a fire at his Hamilton home. His mother Cherie Kingi, 35, suffered critical injuries and is still in Waikato Hospital.