High-rise towers in inner Melbourne may be at risk of damage by fire and the residents could face other safety concerns, an audit of Victoria's building permit system found.
The audit revealed a pattern of poor compliance with regulations.
As fire authorities continue investigating the cause of a blaze at a 21-storey Docklands apartment building last month, The Sunday Age can reveal documents for hundreds of building permits checked by the state's construction watchdog were substandard, with many lacking key fire safety details.
Paperwork for 64 per cent of the commercial building permits audited lacked enough detail and drawings to tell if they met fire-resistance standards, leading the Victorian Building Authority to conclude the "buildings may be a risk to occupants in a fire situation".
It could also potentially lead to "safety issues, particularly the safety of occupants in case of fire and the spread of fire within a building and between buildings".
The statewide audit examined 1000 permits from 20 different local government authorities and found 450 were missing information ranging from minor details to potentially alarming health and safety breaches.
The authority quizzed surveyors about the 450 substandard permits and found 95 per cent "posed no risk to health and safety," the authority's technical and regulation director Jarrod Edwards said. About 1 per cent with serious breaches needed enforcement action, he said.
But with 100,000 building permits issued in Victoria each year, the lack of compliance revealed by the audit sample suggests paperwork for as many as 2250 permits may harbour serious breaches, calling into question the effectiveness of fire safety and other building regulations.
Under Victoria's privatised system, local councils aren't responsible for checking permits for compliance. Private building surveyors lodge files they have approved with councils for storage.
Responsibilty for the system lies with the VBA. Victoria's new Planning Minister Richard Wynne said the number of problematic permits was unacceptable and showed there had been a "systemic failure".
"The investigatory and compliance regime isn't working as effectively as it should," he said.
The audit results and last month's blaze have sparked concern in the industry.
Builders Collective of Australia director Phil Dwyer said the very high non-compliance rates were an "indication of an accident waiting to happen".
"One permit might represent a 70-level tower. If something went wrong, it could be catastrophic," he said.
The audit included 21 multi-storey residential buildings, one of which had fire safety issues that were resolved.
Safety concerns have become more pronounced in the past four years after former planning minister and newly appointed Opposition Leader Matthew Guy sparked a city-wide apartment building boom, approving dozens of tall towers.
Nobody was injured in the Lacrosse building fire, which roared vertically up the side of the building from a lower-level balcony, causing a mass evacuation and $5 million damage, but apartments in the complex suffered water and smoke damage.
As The Age reported on Saturday, residents of the building are now considering launching a class action. Some who fled on the night of the blaze reported fire alarms failed to go off.
Fire investigators are investigating whether materials used to construct the apartment's exterior walls and air conditioning units and other items stored on balconies contributed to the rapid spread of the fire.
"Obviously that material played a big part in this fire," MFB acting director of fire safety Michael Coombes said.
Under current regulations the external walls of taller apartments must be made from non-combustible material but they are not required to be fire resistant.
"In apartments of Type A construction (more than three storeys) the external walls of the building are not required to be fire-resistant if they are non-loadbearing and are situated three metres or more from a fire source feature," Mr Edwards said.
The VBA audit also found about 60 per cent of building plans submitted were "poorly prepared, incomplete, unclear or [had] erroneous drawings [that] can lead to building work being constructed incorrectly and not meeting legislative requirements".
This could have the knock-on effect of causing disputes and litigation, it said.
The authority began the audit in 2012 after damning findings by the state's Auditor-General about the previous regulator, the Building Commission's, lax oversight of industry standards.
