The fire, which broke out on Wednesday, burned through seven of eight apartment towers, home to some 4,600 people, and wasn't fully extinguished until Friday morning.
Officials in Hong Kong said on Monday that the protective netting that covered scaffolding around buildings that caught on fire last week did not meet codes for fire resistance.
Chris Tang, Hong Kong’s Secretary for Security, said samples of the netting were taken from multiple locations from the seven buildings that burned. Seven samples were found to be not up to standards.
Initial tests had suggested the netting was up to standard but investigators had not been able to check all of it due to the fire.
"Because the fire is now out, we have been able to get to places that were not easily accessible before to take samples," Tang told reporters.
The fire broke out on Wednesday afternoon and took until Friday morning to extinguish. At least 151 people were killed.
Donations for the thousands of people left homeless reached 900 million Hong Kong dollars (€99 million), authorities said on Monday, in a massive outpouring of sympathy and support.
A steady stream of people placed flowers, cards and other tributes at a makeshift memorial near the burned out block of buildings during the weekend.
"When something happens, we come out to help each other," said Loretta Loh, after paying her regards at the site. "I have a heavy heart."
The fire broke out Wednesday afternoon at the Wang Fuk Court complex in the suburb of Tai Po. It burned through seven of eight apartment towers, home to some 4,600 people, and wasn't fully extinguished until Friday morning.
Hong Kong police Disaster Victim Identification Unit staff went through four of the buildings over the weekend, finding another five bodies on Monday that took the official death toll to 151. Another 100 people are still unaccounted for and 79 were injured.
On Monday, Hong Kong authorities said teams were assessing the safety of the other buildings, including the one that caught fire first and suffered the worst damage.
The millions of donated funds, and 300 million Hong Kong dollars (€33 million) in start-up capital from the government, will be used to help victims rebuild their homes and provide long-term support, local officials said.
The government has also given survivors cash subsidies to help with expenses, including funerals, and is working to find them housing.
By Monday, 683 residents had found places in local hotels and hostels, and another 1,144 moved into transitional housing units. Two emergency shelters remained open for others, authorities said.
The complex's buildings were all clad in bamboo scaffolding draped with nylon netting for external renovations.
Windows were covered with polystyrene panels, and authorities are investigating if fire codes had been violated.
Residents had complained for almost a year about the netting that covered the scaffolding, Hong Kong's Labor Department said.
It confirmed officials had carried out 16 inspections of the renovation project since July 2024 and had warned contractors multiple times in writing that they had to meet fire safety requirements. The latest inspection was just a week before the fire.
Hong Kong's anti-corruption agency has arrested 11 people, including the directors and an engineering consultant of a construction company.
A growing number of people have been questioning whether government officials should also be held responsible.