The years-long public inquiry into the 2017 blaze concludes the tragedy had no “single cause”, but a combination of dishonest companies, weak or incompetent regulators and complacent government led the building to be covered in combustible cladding that turned a small apartment fire into the deadliest blaze on British soil since World War II.

The inquiry’s head, retired judge Martin Moore-Bick, said on Wednesday the victims’ deaths were avoidable, and “those who lived in the tower were badly failed over a number of years” by multiple people and organisations.

“All contributed to it in one way or another, in most cases through incompetence but in some cases through dishonesty and greed,” he said.

While the report might give survivors some answers, they face a wait to see whether anyone responsible will be prosecuted.

Police will examine the inquiry’s conclusions before deciding on charges, including for manslaughter, but say any prosecutions are unlikely to come before late 2026.

Natasha Elcock, of Grenfell United, a group representing survivors and bereaved families, urged authorities to “deliver justice and bring charges against those who are culpable for the deaths of our loved ones”.

Prime Minister Keir Starmer apologised on behalf of British state, saying the tragedy “should never have happened” and promising the victims justice.

The fire broke out in the early hours of June 14, 2017, in a fourth-floor apartment and spread up the 25-storey building like a lit fuse, fuelled by flammable cladding panels on the tower’s exterior walls.

The tragedy horrified the nation and raised questions about lax safety regulations and other failings by officials and businesses.

“How was it possible in 21st century London for a reinforced concrete building, itself structurally impervious to fire, to be turned into a death trap?” the report asks.

“There is no simple answer to that question.”

Grenfell Tower had been covered during a refurbishment with aluminium and polyethylene cladding – a layer of foam insulation topped by two sheets of aluminium sandwiched around a layer of polyethylene, a combustible plastic polymer that melts and drips on exposure to heat.

The report is highly critical of companies that made the building’s cladding, saying they engaged in “systematic dishonesty,” manipulating safety tests and misrepresenting the results to claim the material was safe.

The combustible cladding was used on the building because it was cheap and because of the incompetence of architects, engineers and contractors who all thought safety was someone else’s responsibility, the report says.

The inquiry concludes the failures multiplied because bodies in charge of enforcing Britain’s building standards were weak, the local authority was uninterested and the “complacent” Conservative-led UK government ignored safety warnings because of a commitment to deregulation.

The inquiry’s initial report published in 2019, looking at what happened the night of the fire, criticised firefighters for telling residents to stay in their apartments and await rescue, leaving it too late for many on the upper floors to escape.

London Fire Brigade came in for further criticism for poor leadership, and for providing firefighters with inadequate equipment and training.

The Grenfell tragedy prompted soul-searching about inequality in Britain.

Grenfell was a public housing building set in one of London’s richest neighbourhoods, and many victims were working-class people with immigrant roots.

However, the report says the inquiry saw no evidence that racial or social prejudice influenced decisions that resulted in a dangerous building or the spread of fire.

After the fire, the UK government banned metal composite cladding panels for new buildings and ordered similar combustible cladding to be removed from hundreds of tower blocks across the country.

But it’s an expensive job and the work has not been carried out on some apartment buildings because of wrangling over who should pay.

The report’s recommendations include tougher fire safety rules, a national fire and rescue college, and a single independent regulator for the construction industry.

– AAP