More than 400 apartment owners in Melbourne have been ordered to replace non-compliant external cladding after a devastating fire hit their building last November.

The blaze at the Lacrosse block in Melbourne’s Docklands spread rapidly thanks to flammable cladding called Alucobest, which had been imported from China and not tested to Australian standards.

“The Municipal Building Surveyor has issued the orders after previously giving owners the opportunity to provide an alternative building solution to replacing the cladding,” a spokesman for Melbourne City Council told insuranceNEWS.com.au.

“This is to bring the building into compliance with the Building Code of Australia.”

The cladding must be replaced within 350 days and owners have 30 days to appeal to the Building Appeals Board of Victoria.

The owners are believed to be considering a class action against, among others, the builder and building surveyor.

Meanwhile, the Victorian Building Authority (VBA) says the construction industry has an “inconsistent understanding” of how aluminium composite panels (ACP) should be used.

The VBA is auditing 170 Melbourne buildings following the Lacrosse fire, and has released initial findings.

“Several brands of ACP have been used for cladding the external walls of public and residential buildings in central Melbourne and immediate surrounding suburbs,” it says.

“However, apart from the Docklands apartment building, the use of the Alucobest-branded product has only been identified in two buildings to date.”

The VBA says ACPs are often used on external walls for decorative purposes, but no single builder is consistently responsible for non-compliant use.

“Decisions made by different [builders] at different stages of the building process have contributed to ACP being used in ways that do not comply,” it says.

“There appears to have been an inconsistent understanding among the building industry of the requirements of the [code] in relation to the use of ACP.”

Buildings featuring non-compliant panelling have included an aged-care facility and hospitals.

The VBA stresses a building can still be safe to occupy despite the presence of non-compliant panels, because other features such as sprinkler systems can prevent the spread of fire.