After hearing from building owners who want to be compensated for dangerous combustible cladding on their property, a judge will hear defences to these claims by firms that produced and imported the products.
German manufacturer 3A Composites and its Australian distributor Halifax Vogel Group (HVG) are in court, sued over a type of cladding linked to several disastrous blazes worldwide.
This includes the Lacrosse fire in Melbourne in November 2014 and the Grenfell Tower inferno in London in July 2017 where 72 people died.
A class action has targeted two brands of cladding manufactured by 3A: Alucobond PE, which is banned in Australia, and Alucobond Plus, which has been sold to architects and builders as a more fire-safe solution.
The Federal Court previously heard this type of cladding, which has a flammable polyethylene core, could ooze, melt and deform, ultimately aiding the spread of fire throughout a building.
The building products were marketed as safe by both 3A and HVG without any warnings as to the fire dangers the components presented, Justice Stewart Anderson heard previously.
The class action claims the building products were not of merchantable quality and that marketing material contained misleading and deceptive claims about the safety of the panels.
On Wednesday, the judge will hear submissions by 3A's barrister Matthew Darke SC and HVG's barrister Nicholas Owens SC about why the firms should not be liable for compensating building owners.
The companies have claimed that the fault lay with architects who did not properly assess whether the cladding could be safely installed in the buildings they were designing.
3A also denies it marketed the material or it even carried out business in Australia, because it is a German company.