The Grenfell Tower inferno would not have spread claiming 71 lives if the building had not been refurbished, a major report has found as lists a litany of fire safety failings.

The report, prepared for the Metropolitan Police as part of their investigation into the tragedy, details five breaches of building regulations including the use of combustible cladding and insulation and gaps in the structure and window frame that helped fan the fire.

It leads to the conclusion that had the refurbishment not been carried out it would have been difficult for it to spread beyond the fourth floor flat where is began in a fridge freezer in the early hours of June 14 last year.

A draft of the 200 page report prepared by fire investigation experts BRe Global, dated 31 January 2018 and leaked to the Evening Standard, says: “Grenfell Tower, as originally built, appears to have been designed on the premise of providing very high levels of passive fire protection.

“The original facade of Grenfell Tower, comprising exposed concrete and, given its age, likely timber or metal frame windows, would not have provided a medium for fire spread up the external surface. In BRE’s opinion … there would have been little opportunity for a fire in a flat of Grenfell Tower to spread to any neighbouring flats.”