The combustible insulation and cladding that burned on Grenfell Tower will not be banned if the government accepts the findings of the official review into building regulations and fire safety in England.
Dame Judith Hackitt's report, being published this morning, will criticise what she calls systematic flaws in the system of how buildings are planned, built and managed which she believes are putting people's lives at risk.
But according to a source briefed on the findings, her report stops short of calling for significant changes to the existing regulations.
Instead she is expected to recommend additional measures including holding developers and building managers responsible for fire safety and the creation of a new body to ensure the rules are followed.
Seventy-one people died in June 2017 when fire spread up Grenfell Tower's external combustible cladding which had been fitted to meet energy saving targets.
Almost three hundred other high rise buildings were subsequently found to have unsafe cladding and the government said on Wednesday it will provide £400m to replace it on 158 social housing buildings.
Dame Judith's refusal to call for a ban on combustible cladding and the desktop studies that are used to authorise cladding systems that have not been fire-tested is being criticised.
Shadow Housing minister John Healey said unless both are banned the report will fall "well short" of what is needed.
"The bare minimum of big changes in the system must be an end to any combustible material on the sides of high rise tower blocks, an end to this so-called desktop study which is a paper-based way of getting around testing material and allowing them to be put on buildings and certified as safe," he said.
The Royal Institute of British Architects has campaigned for a ban on combustible cladding and says above all its members need clarity.
Executive director Adrian Dobson said: "We and our members will have to work within whatever regulatory regime is proposed, if it's adopted by government, and obviously will continue to do so.
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"But at the same time if we don't see these basic clear requirements which we think are necessary in order to assure the public and give the industry clear guidelines that are enforceable and we can all work towards, we'll continue to campaign for those basic requirements that we think are needed."
In a brief statement ahead of the report's publication the Ministry of Housing, Communities and Local Government said: "The report is forward looking and focused on establishing a sufficiently robust regulatory system for the future, in this way providing assurance to residents that the buildings they live in are safe and remain so."