Cheap non-compliant apartment cladding often makes use of glue, cork and other flammable materials and early analysis suggests it may have been linked to the engulfing of a 24-storey high-rise in London's Grenfell Tower within minutes and other conflagrations.

But Australia's authority on fire protection has warned the use of such material presents a latent safety danger for Sydney, which is in the middle of a historic, sustained apartment construction boom.

"We've developed a culture of saying this looks like any other material ... it's fine," said Matthew Wright, the deputy chief of the Australian authority on fire protection, the Fire Protection Association of Australia.

The NSW government, in the wake of a 2014 Melbourne apartment inferno, used national statistical and building approvals data to determine as many as 2500 buildings could be clad in the dangerous material, according to an opposition request under freedom-of-information laws.

But the state government on Thursday played down those figures as "not representing the scale or number of affected buildings", and said neither data set included information about the materials used in the 2500 buildings.

"We are at this point today where we simply don't know the dangers that are lurking in some high-rise buildings," said Labor's shadow better regulation minister Yasmin Catley.

The Melbourne Lacrosse apartment fires in 2014 engulfed a residential tower in close to 15 minutes but without any loss of life.

A survey of new buildings in the Victorian CBD, based on a sample of more than 150, found up to half of them used combustible cladding.

Planning Minister Anthony Roberts said the government had reacted immediately after the Melbourne incident to educate councils, who approve development applications, about the dangers of unsafe cladding.

"My agency will monitor the investigation into the London fire to determine whether there is any relationship with the combustible cladding matter and whether any further action should be taken," said Mr Roberts.

A department of planning spokesperson said the presence of aluminium composite cladding on a building "does not mean it is non-compliant or a safety hazard, the configuration and how it has been used will also be relevant".

Hills Shire councillor Raymond Harty, who runs a training company for construction companies, said the state government needed to overhaul the certification regime for buildings.

"As councillors we can only do so much there have been so many cases where private certifiers who have signed things off that don't meet the conditions," he said.

The state government announced in September plans to rewrite the Building Professionals Act in response to a scathing review by former Treasury secretary Michael Lambert following a fatal fire at a Bankstown block, dealing especially with defensive measures such as sprinkler systems.

Better Regulation Minister Matt Kean's office did not on Thursday say whether the state government would conduct an audit, which insiders say would be very difficult to undertake.

Local Government NSW president Keith Rhoades said councils did their best to crack down on developments found to contain non-conforming building materials, but said there was a "weaknesses in our national system" because "no single organisation is responsible for certifying products as being compliant with the standards".

Robert Marinelli, a member of the Association of Accredited Certifiers, also supported the call for greater scrutiny of material but warned against panic.

"We have a highly regarded regulation system ... close to the best in the world," he said.

Stephen Netting, from Fire and Rescue NSW, said the fire department received complaints about shoddy building materials but did not have the resources to inspect every apartment building after it was certified, making it impossible to know "how big the problem is".