Up to 1,000 recently completed Sydney-based apartments are now at risk of total collapse due to “serious damage” to concrete in basements, according to the New South Wales building watchdog.
On Monday, Greenland – one of China’s largest real estate developers, was issued an urgent rectification order over four apartment buildings at the Lachlan’s Line development at 23 Halifax Street in Macquarie Park and provided 14 months to repair “shoddy works.”
According to NSW’s Deputy Acting Building Commissioner, Matt Press, “the issue compromises the concrete slab’s structural performance and adequacy,” and “As a result, it is likely to cause the concrete slab to be unable to withstand the carpark and ground floor loads.”
The project is the latest concrete-based high rise at risk of collapse, highlighting the difficulties of using heavily loaded concrete when designing and using concrete products in the foundations of buildings.
“We must realise that such mass concrete structures are three times heavier than a mass timber equivalent,” a Sydney engineer told Wood Central last year (after the high-profile Mascot Tower collapse).
“That’s a hell of a difference when designing foundations,” he said. “So, it’s a no-brainer that timber greatly reduces the risk of a foundation failure; it’s much lighter than concrete.”
In the defect rectification order obtained by Wood Central, the Building Commission found that “serious damage and spalling of the concrete slab at the joint locations in basements and the ground floor caused by defective workmanship.”
It also confirmed that the cause was “a defect in a building product or building element that causes or is likely to cause the basement slab to fail, namely, to fracture and collapse, leading to the destruction of the building or any part, or the threat of collapse of the building or any part.”
The Lachlan’s Line development features a “range of stunning apartments” that were “perfectly positioned above a bustling town square,” according to information on the Greenland website.
“Featuring impressive interior design touches in every room, from quality timber floorboards to distinctive black tapware and superior stone-based kitchen benchtops.”
Documents show the commission informed the developer, local council and owner corporation in late October that it intended to issue a rectification order, sharing a draft copy. According to the commission, Greenland responded by the start of December with two specialist reports and a request that the order not be issued.
“The developer also requested amendments to the periods of compliance, the areas required to be slab scanned and the number of expert reports required under the order,” the order read.
The order “notes the developer’s request that the department exercise discretion to not issue the order. In circumstances where the defect is not disputed, I believe it is appropriate to issue the order.”
Greenland Group is one of China’s largest real estate developers and is one of the Chinese conglomerates fuelling the global timber supply chain. It is also at the forefront of the build-to-rent movement that is taking the Australian property market by storm.
Last week, NSW Building Commissioner David Chandler offered owners of apartments in Sydney’s Mascot Towers a lifeline after facing significant repair bills from cracks discovered in the basement in 2019.
If approved by the owners, the deal would wipe the debts of unit owners and will give owners less than the original purchase price.
Nonetheless, it would allow residents with outstanding strata debts and mortgages on the 11-year-old building – deemed too expensive for the strata to repair – to walk away from their losses.
- Greenland has no involvement with the Mascot Towers development.
