A review of building regulations set up after the Grenfell tragedy will not propose an outright ban on flammable cladding, the BBC understands.
Dame Judith Hackitt is instead likely to call for a new system for managing building safety when her government-commissioned report is published later.
Architects, building firms and Grenfell survivors had backed a ban on using combustible materials in construction.
Seventy-one people died in the fire in the west London tower block last June.
Following the fire, cladding on hundreds of buildings failed safety tests.
On Wednesday, the government announced a £400m operation to remove dangerous cladding from tower blocks owned by councils and housing associations.
Dame Judith’s independent review, commissioned by the government, has been looking into regulations around the design, construction and management of buildings in relation to fire safety.
In her final report, to be published on Thursday morning, Dame Judith – a senior engineer who used to chair the Health and Safety Executive – is expected to stop short of a complete ban on so-called combustible cladding.
But it is understood her report will find building regulations are complex, confusing and not fit for purpose, the BBC’s home affairs correspondent Tom Symonds said.
She will propose a tighter system of safety management throughout the life of a building in England, which would be led by the construction industry.
According to Tom Symonds, the approach may be criticised by those who believe the Grenfell fire happened because regulations were too confusing and weak to stop construction companies exploiting them to cut costs.
Dame Judith’s appointment to lead the review had been met with some criticism due to her former role as director of the Energy Saving Trust. The organisation promotes insulation containing a foam known as polyisocyanurate (PIR), blamed for fuelling the fire at Grenfell.
But the government said Dame Judith was “an independent and authoritative voice”.
Her review is aimed at making sure similar events do not happen in the future. It is separate to the judge-led inquiry into the Grenfell fire, which will start taking evidence on 21 May.
Dame Judith’s interim report, published in December last year, found building regulations were leaving room for shortcuts.
She said she was “shocked” by some of the practices she had seen and a “cultural change” was needed. The fire “should not have happened in our country in the 21st century”, she added.