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Creaking and cracking noises are common in tall buildings from my experience, but in this case it seems an actual crack in the structure has been found
But not suddenly starting and running for the course of an hour or so, and audible from neighbouring apartment blocks.
To any structural engineers, what kind of tolerance are buildings like this usually built to?

How much movement can they take? 2mm doesn't seem like much at all.

Also depends on what moved, and in which direction. I’m sure the building sways much more than that in the wind, or expands more than that on a hot day.
2mm is fine and normally within measurement error.

However, buildings should be designed to not fail disproportionately, so there isn't sudden failure such as like with the Miami footbridge. Design errors can lead to sections being over reinforced or other issues which could lead to collapse with little warning, which is what the concern will be.

Edit : also with cracks it depends on where they are and what causes with them. Cracks are normal for concrete and the size should be controlled through detailing. Where cracks are larger than this it can indicate whether there are issues in bending/shear. Structural design also often takes into account behavior of cracked concrete.

Buildings are designed to move, because that's the way they absorbe energy without suddenly breaking. The deformation up to breakage is deemed to be in plastic mode, so the building "advises" when something is wrong by exerting plastic deformation and cracking. The modern building code of australia is aimed at plastic deformation, and the formation of fissures, that's considered a fair balance between safety and cost. The deformations seen in this building are in the millimetres, but if doors and windows are jammed, then there is a more serious problem, it could be a foundations' problem, it could be the precast system problem, it could be the main frame, or anything in between. I am an unemployed civil engineer because companies fill their vacancies with adventurers from overseas, pakistan or Filippines for example. I have been forced to work as a draftsman while these people, often on working visas take all the jobs, because they are cheap professionals and workers. this is how low the professions are falling in Australia. I don't see the moment to finish my masters and run from Sydney. I am sick of the things I am seeing here.
Will insurance cover this if the building is no longer safe for residents?
Not if the insurance companies can help it.
Theoretically the system is set up to do this but in practice its complex and takes time.

Insurers and lawyers can have a field day over liability. Was it the builders fault? The structural engineer? The architect? Or caused after construction? All of these will have their own insurance and all will avoid paying unless its clear to a court that its their liability.

Of course major issues like this dont happen so often so theres little to reference. But for example there was a recent case where the owners corporration insurance refused to pay for a roof flying off after a storm because in their view poor construction was to blame. Its a lot of time for residents to be without a home while these things are sorted

https://www.smh.com.au/national/nsw/insurer-rejects-stormdam...

In Sydney it's also common for builders/management companies/etc to declare bankruptcy to deflect lawsuits etc, then set up a new company to continue business.
They also don't have to finish everything in the building. Moved into a building where the construction company did this, many things were unfinished. Apparently didn't completely pay the workers, so they just took stuff when they left.
> It's a lot of time for residents to be without a home while these things are sorted.

Though if you're renting, you can break your lease without fees and get your bond back if the building is no longer classified as being safe to live in (at least that's the NSW rental laws).

But of course if you're renting then home insurance isn't your problem (usually you'd just have contents insurance).

Apparently, this is one of the dodgier parts of owning a condo. The condo we used to own had a structural problem - nothing major, but one that needed to be repaired in the next several years, or else it would get worse.

Getting the builder to pay up was very, very hard. Multiple shell corporations, numerous lawsuits, debates on whether this was construction defect, or an insurance claim. The way condo association finally won was by hiring a rather expensive law firm. It took several years, and in the end, a big chunk of the judgement went to the law firm.

And this was for a rather large condo building with 170 units. We were lucky we won, or else all the owners would have had to pay a one-time assessment.

My real estate agent at the time warned me to be careful about buying condos that are less than 5 years old, as that’s the typical time frame when various surprises come out. I am taking that advice to heart.

Fascinating post by a structural engineer who actually inspected projects by this firm is over in the reddit discussion. https://www.reddit.com/r/sydney/comments/a91wit/opal_tower_s...
Feels like I could write the exact same post about software engineering. Some party apply directly (copy-paste with some crucial yet infinitesimal differences).
I've lived in a Meriton apartment complex in Sydney. It was one of the complexes built right in the biggest part of the boom, when they were rolling out "largest development in Sydney/Australia" one after the other, trying to outdo themselves and each other.

We moved in (renting) when it was brand new, peeling the plastic off the appliances etc. Within 1 year they were doing MAJOR fixes to building-scale defects in the construction, and within 2-3 years we had cracks in the walls, paint flaking off, doors that didn't line up, windows that didn't seal when closed. This is on a ~8th level apartment, and these aren't cheap apartments. They're not luxury, but they're comfortable in the "mid-to-high" end of the Sydney scale, just on the edge of the CBD.

We since moved out of Sydney, but we'll never live in a new-build Apartment again. The hell we went through, just as a renter in those few years, was mind boggling. Giving engineers and tradies access to our apartment seemingly every week, sometimes every day for days on end, so they could inspect and fix issues. I can't even imagine how bad it is for people who got suckered/conned into buying those POS apartments.

My experience of equivalent buildings in Melbourne matches up. Leaks and cracks all over the place. All these building seem to be built out of prefabbed concrete panels in a hurry. Bonus points if it's also covered in a flammable cladding.
Yeah we moved from Sydney highrise hell directly into Melbourne highrise hell (we thought Melbourne might be better... Oops) and received a flooded 10th floor apartment in a 1 year old highrise because they "forgot" to seal where the wall concrete meets the floor concrete, and an exterior ledge pooled water until it seeped through the cracks and flooded our apartment.

Multiple weeks with 2 adults and 2 kids and all our belongings in the single dry room while they stripped the inside and outside of our apartment to bare concrete, sealed it all, and rebuilt all the interior, drywall, carpets, etc.

Because we rented, we received no compensation or assistance. Yay Victorian tenants rights (or lack thereof).

We're now in a 30yr old double brick house (with all new high quality interior) in a rural city and never been happier. We'll never live in an apartment or major Australian city again.

Meriton is extremely well connected politically. NSW (the state Sydney is in) has always had a problem with corruption stretching back to the Rum Rebellion [0]. If you are thinking of buying a new apartment in Sydney then just walk away, if the developer is Meriton then run.

0. https://en.m.wikipedia.org/wiki/Rum_Rebellion

Connected politically or not means squat if you build a structure that collapses killing hundreds of people. At least I hope that is the case in any place under rule of law. Of course I would hate to see any kind of building failure that causes mass casualty. But are the execs of Meriton aware of such possibility?

I am reminded of the Sampoong Department Store collapse in Seoul, Korea. This happened in 1995. This was a very high end department store from what I heard. I know acquaintances who know of a family that lost multiple family members.

The family that owned the building was one of those chae-bul family in S. Korea with multiple business interests. I believe in top 50 at the time or something like it. So yes they were politically connected. But because of the catastrophic failure of the building with mass casualty, the family's entire holding was liquidated to pay for compensation to the victims' families. And the owner/owner's son both served lengthy prison terms.

Edit: While reading up on Sampoong incident, I learned the owner wanted original construction firm to take shortcuts to reduce cost, but they refused. So the owner fired the firm and started HIS OWN construction firm to build the building. At least someone had a backbone, stuck to what was right, and lost a big job/contract, but was proved to be in the right. I bet someone at the original construction firm let out a huge sigh of relief later.

Any problems regarding Meriton don't seem to be well documented. The only issue on its Wikipedia page is a fine for manipulating TripAdvisor reviews.
Yes when your buildings collapse you will find you have problems bigger than your political friends can help you with.

Meriton is competent enough to put up buildings that won’t fall down on their own.

Have a look at the James Hardie Industries case to see how large Australian companies avoid legal consequences for killing large numbers of people.

"The total number of past and future claims made against James Hardie for asbestos-related diseases is estimated to be more than 12,500, of which 8103 will be claimed after 2006."[1]

[1]:https://en.wikipedia.org/wiki/James_Hardie_Industries

> Connected politically or not means squat if you build a structure that collapses killing hundreds of people. At least I hope that is the case in any place under rule of law.

I wouldn't count on that. 18 months later there have still been no prosecutions (or even open court cases AFAIK) regarding the Grenfell Tower disaster. It'll most likely be years or decades before that happens.

If it turns out this was caused by someone being negligent, they will continue endangering the lives of other people until that happens.

No case against the government/council? It was the fucking lack of regulation.
A London plumber told me once he spends a lot of time in super poorly made new builds. Construction firms build them super shitty but with a five/ten year guarantee, take the money, then declare themselves bankrupt. The guarantee is worthless because the firm is gone, they make a ton of cash on the build, they set up again and rinse and repeat. I assume it's a little more complicated than that, but he said he'd seen it a lot and spends a lot of time fixing problems he shouldn't. Is this similar in Sydney?
Yup spot on. They're famous for going bankrupt and reappearing under new names.
Phoenixing - ASIC was meant to be cracking down on that but I hear from ppl that work there they cant be bothered with small companies and mainly want to focus on banks etc.
This was the underlying plot of the movie Jack Reacher; shady construction firm that goes from city to city.
So the usual Meriton SOP is to retain control of the body corporate for the duration of the builder’s liability so that they can’t start proceedings against the builder (Aus strata title, body corp coverered here: https://www.lawsociety.com.au/for-the-public/know-your-right...).

Strata title laws have been changed recently, but the system is slow to catch up to these cowboys.

Reading that post and having worked in various contractor roles in construction in Sydney over the last 5 or so years (concreting and general construction) none of what he is saying surprises me at all!

I came from construction out in the mines so OH&S and engineering inspections were quite literally our daily jam, moving to the construction industry for residential/commercial in Sydney I was blown away by what I saw!

We would quite literally have days where the site would be filled with teams of workers brought in on buses, mixtures of migrants from eastern europe (like bulk euro's) and parts of asia who would be PUMPING out the welding, concreting and general construction. The site would literally be buzzing with activity...then you would rock up the next day and the place would be near empty...jobs half done all over the place. Sometime during the empty days...the inspections would happen, be they OH&S or engineering or whoever else had to suss shit out to tick some boxes.

Point is, they would actively pull guys off site because these teams were dodgy as shit at working, I spent my days regularly just counting the OH&S breaches I witnessed. Hell I even called the asbestos investigation team on a company I worked for because the breaches were just too ridiculous for me to handle...nothing happened. Kents are still making their workers rip out asbestos with no protective gear and making a shit ton in profit because they dump it using businesses that dump it illegally. These are MBA registered businesses too, and don't even begin to think the MBA doesn't know this shit goes on regularly, its a large portion of their members participating in these acts. They are dodgy as hell.

/rant

Unfortunately this all matches the stories my friends tell me :(

For our US friends MBA is the Master Builders Assoiciation [0], not people with a Masters of Business Administration.

0. http://www.mbansw.asn.au/About/

It happens in the US too: https://en.wikipedia.org/wiki/The_Harmon

At least they caught it before it was fully constructed, but it still cost almost as much to tear it down as it did to build!

In your wiki link it says the tear down was expected to cost $11.5 million which must be much lower than construction costs. (quick search says $275 million to build) In general it only makes sense that demolition is much cheaper than construction.
I once had a dodgy builder doing work at my place (I didn't realise he was dodgy until it was too late). He had MBA stickers all over his van. I took some photos of it and sent it to them saying he was fraudulently using their name when not a member. Their response was well we can send him an application. Never mind that he had loads of fines and on-going investigations by fair trading.
Shit like this is what wikileaks had promised us.

Those businesses should learn the hard way why it should be cheaper to do it correctly.

I wonder about the human effects of safety engineering. Say you require a 10x margin because you know builders will dilute it to 5x undetectably (say it’s under layers of other material or something). Every time you attempt to compensate for the dilution of the standard in practice, they’ll undo it. But if you stop, they may continue increasing the dilution. There’s a normalization of deviance. And indeed most buildings will still stand because the standard is attempting to handle six nines so everyone involved building will probably ever build something that fails even if they diluted it to five nines.

How do you encourage not doing that? Enforcement is one angle but are there others? Force the buyers to have insurance and then let the insurance company eat the risk assessment?

> But if you stop, they may continue increasing the dilution. There’s a normalization of deviance.

For a very good explanation of the mechanism that causes this kind of normalization of deviance, I recommend Richard Cook's outstanding talk "Resilience In Complex Adaptive Systems"[1].

[1] https://www.youtube.com/watch?v=PGLYEDpNu60

Well one option is to hold designers, developers, builders and inspectors separately liable for the work and inspections they do for their entire lives, not limited to the period of solvency of the company they did the work for.

We’ll see a return to very conservative designs though, with no 100 storey skyscrapers until they find people actually willing to pay for and perform good work.

Until we are actually sending people bankrupt or jailing them, the corruption will worsen. There has to be some actual penalty for people trying to pass off shonky work.

Does this, in practice, mean quality? The aeroplane industry doesn’t do this and they build safe craft.
Aerospace industry has a deeply engrained culture of safety, and improving from failure. Construction industry has a history of building to bare minimum requirements, organized crime involvement, corruption, and passing the buck when anything goes wrong.
I dunno, I'd say there's a very long tradition of safety in construction.

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death." (Code of Hammurabi)

I look at that the other way.

The need for effective regulation and proper enforcement come with a long tradition in construction business.

FAA certified mechanics and inspectors are held personally liable regardless of who they are working for and what they are working on.
This can also be handled by market forces. The people who expect to buy the apartments in a high-rise like this could collectively hire their own inspectors during construction, which would be answerable to them alone. The obvious way to collectivize this is through insurance.

The problem stated by the linked Reddit commentator happens because the interests of everyone (architects, engineers, constructors and inspectors) currently align to de-prioritize safety.

There's numerous reasons why that doesn't happen. One being that no individual apartments might have been sold before the construction is finished, but another reason could be that building codes have been good enough, so people think of that as a waste of money.

But as a neighbour, I don’t want the building to fall on me. Part of the risk is externalized. Do I get to send an inspector too? That over privileges me because then I can stall projects by claiming an ostensible high threshold of risk.
You couldn't stall a project by holding it to a higher standard than the building codes supposedly being violated (if the Reddit OP is to be believed).
Fair point. If the standards were inflated we'd have to bring them back down (which may be politically infeasible) but what you say sounds fine.
Privately hired inspectors is a terrible idea. That leads it to only the rich being able to afford to buy good inspectors leading to only the rich getting safe housing.

Your whole comment can be condensed down to "I think poor people should have to live in dangerously built housing and die but it'll be their own fault for being poor."

There needs to be much more regulation with much higher penalties for failures, and a dismantlement of the incentives of corruption.

Consumers feel like they need to consider the safety rating of cars they buy, and they pay to e.g. buy brands like Volvo or Tesla known for exceeding the bare minimum when it comes to safety.

Yet I don't think you'd say that someone advocating that we continue that system thinks that poor people should drive dangerously built cars, and it'll be their own fault of they die in car accidents.

I'm pointing out that it's interesting that there seems to be no analogous mechanism to ensure safety when it comes to buying houses, which are a much bigger investment than a car.

> There needs to be much more regulation[...]

If the Reddit OP is to be believed the problem isn't that there aren't regulations, but that they're systematically not being enforced.

> [...]with much higher penalties for failures[...]

I doubt that would work as well as aligning incentives. Even if you gave engineers the death penalty for cutting corners they stand to make a lot of money, and most of the time they'd get away with it. How many buildings in Sydney aren't in the news?

> [...]a dismantlement of the incentives of corruption[...]

The best way to dismantle such incentives is to ensure that there's conflicting interests. Here buyers are being screwed over by the builders, certifying authorities and the councils because the interests of all three align to screw buyers over.

> I doubt that would work as well as aligning incentives. Even if you gave engineers the death penalty for cutting corners they stand to make a lot of money, and most of the time they'd get away with it. How many buildings in Sydney aren't in the news?

In the US, Canada, and I presume Australia, the design engineer is actually separate from the contractor. Generally, there is a developer who pays all the design consultants and the contractor to make the project reality. So the engineer really doesn't stand to make money from cutting corners. In fact, they have much to lose, including their ability to continue practicing engineering (it's a regulated profession) Their fee is the same if it gets built correctly or not, and it costs them nothing extra to ensure it's built correctly and mistakes are rectified.

> Your whole comment can be condensed down to "I think poor people should have to live in dangerously built housing and die but it'll be their own fault for being poor."

I think this is accidentally being uncharitable. It's possible that GP did not think all the way through to the conclusion you saw. A more accurate inference that doesn't assume hatred of the poor from GP would be something like "this will lead to a system where only the rich can verify the quality of housing" and stopping there.

A friend's father was working as a private safety inspector after retiring as a civil engineer.

One day someone came to him, offered him additional payment to ignore cost skimming, and told him he's got a nice family and that it would be a shame if something bad happened to them. He quit the same day.

When you have organized crime involvement market forces cannot be relied upon.

This is why there are phased inspection requirements along the buildout - so, when struct finishes/is in progress, an inspection is required to be passed prior to next phase.

The real problem is in the purchasing of Chinese Steel, which supposedly passes muster, but clearly cannot. Hence, Bay Bridge.

But - IMO - this is what was so fucking shady about taking all the steel from the towers on 9/11 and shipping/selling them off to china.

Then we pull a PR Bullshit move of "incorporating" some of the steel in a fucking destroyer ship as some limp "Freedom Flex"

The incorporation of tower steel into a war vessel was a fuck you from the people who profited off the event.

As far as I remember, many of the steel failures on the Bay Bridge were US steel from Ohio through Dyson.
>The eastern span of the Bay Bridge was completed in 2013, six years behind schedule and billions of dollars over budget. Critics say pressure to contain costs and meet deadlines led to poor management decisions, including the use of substandard ---- Chinese steel. ---- Other problems include cracks in the foundation and missing sections of deck drainage that allow rainwater to bleed inside the structure.

https://www.courthousenews.com/engineer-unfazed-reports-subp...

---

There are other articles about it...

> Less than six months after the ill-fated batch of rods arrived in California in 2008, six high-strength rods that Dyson Corp. of Ohio shipped to rebuild the Hood Canal pontoon bridge — which connects the Kitsap and Olympic peninsulas in the western part of the state — failed within days of being installed, according to a review recently made public by California bridge officials.

Right but there are also articles about Dyson Steel:

https://m.sfgate.com/bayarea/article/Bay-Bridge-supplier-fai...

I chose my words carefully. I didn't intend to say that Chinese Steel is magic. Just that they're not the only culprit. If we'd picked up more Ohio steel we'd probably be in the same situation.

Theres a whole field of structural reliability, and it's where they come up with load and resistance factors for design equations, and material testing requirements. I believe the targets are such that the probability of collapse of any structural component over it's lifetime is less than 10%, if it was designed for a utilization of 1.0. In reality, sizes are bumped up so the probability should be even less.

In countries with strong regulatory requirements, you generally don't have to worry about builders 'diluting' because it is inspected by the design engineer and tested by 3rd party testing companies. It is in the engineers best interest to ensure compliance because they are legally liable in that regard. You can actually be suspended from practicing engineering if you do not comply with field review requirements. If our design calls for 35MPa concrete, samples are taken at the job site, tested, and reported back to the contractor and designer. If they come up short, it gets remediated.

The issue is that components dont build systems. Sure, maybe that get concrete that tests to 35Mpa. But was the embedded steel reinforcement coated properly, or will it rust? Were the balconies and doors sealed? Did anyone wash grout down the drains? And then imagine someone finds a problem, like “leaks” in a sibling comment. Do they revisit the strucutral issues that led to it? Or do they patch it up with a new 3rd party tradie and walk away?

The idea being that your point inspection are finite. And the responsibility will be laundered behind a legal or organizational structure. Youre not going to reach anyone “responsible” for systemic issues. And as soon as you do that youll dampen all relevant investment activity. See the Washington State Condominium Act for a great example.

And yet the UK continues to have mini-scandals :

https://www.bbc.com/news/business-46454844

Not sure about UK, but where I'm from this type of single family home construction discussed in the article doesn't normally require a structural engineer. In that case, you really are depending on the reputation of the builder.
Encouraging is easy - put in jail everyone who knew about failures in the process, from the lowest ranking engineer to the top-management, if they were aware. It will put hundreds of people behind the bars at first, but the rest will be more than happy to follow the safety rules instead.
The process would also become a game of whack a mole with safety regulations, as everyone falls over themselves to point out every real or imagined flaw.
I've never heard of anything like this. What happens now? Do they have to demolish the entire building and start from scratch?
> I've never heard of anything like this.

This is kind of small compared to the Millennium Tower in San Francisco. https://www.cbsnews.com/news/millennium-tower-san-francisco-...

I lived right near that thing and knew it was sinking a bit, but had no idea it was leaning so far and with cracks too. WOW! That's terrifying, and I'm more relieved than ever to be away from that thing.

Do you think anyone is going to do anything about this before a catastrophe?

I don't track it, but last I heard there was a proposal that would cost ~$100M to drive micropilons down to bedrock, which is what should have been mandated in the main design to begin with. https://www.sfchronicle.com/bayarea/article/Millennium-Tower...

Some windows are starting to crack as well. https://sf.curbed.com/2018/9/7/17829328/millennium-tower-win...

I recall early stories about Millennium Tower and the builder basically claiming, through a law firm, that it was a normal amount of settling and everything was fine. Nothing to see here....

And I bet the same sort of response will come from the builder of Opal Tower in Sydney.

That's always how it starts, and it always ends with the developer, architect, builder, residents, and local government suing each other for years on end.
Here is my personal opinion on the reason why it was thought to be a reasonable amount of settling: that they were looking at simply the individual millenium towers' effect on the overall area -- but with the addition of the transbay terminal next door - the major excavation which occured with that - then the new load of the salesforce tower and the transbay terminal (which also had been closed due to cracking and settling issues and needs to be jacked up -- I think that whole lot of struct/civ engineers are at fault of being short-sighted about the surrounding load impact on the greater financial district and the standards which were previously thought to be adequate.

So - you have the millenium tower, which was completed prior to any of these ancillary loads were put on the area - but is effectively being squeezed out and squished, and even the most micro-shifts in the foundations of Millenium Tower will be amplified by its mass+height -- but as it was already into a settled-ish position, its now getting worse after its' settling is further distressed due to even a millimeter shift in the lateral load due to compression from and settling of the new towers/terminal....

Millennium Tower will be a multi-decade lawyer-fest. At least four or five parties will be suing each other: The designers, the builders, the city, the apartment owners, insurance companies and probably the neighboring building owners. What a mess.
I live in Sydney and I wouldn't buy any property built since 1970 and especially any property built since 2000.

I have friends in the industry and the horror stories they tell me are shocking. The real problem is coming in a few years as the waterproof membranes protecting the rebar in all these high rise buildings has in almost all cases not been put in correctly - in 10 to 20 years the concrete cancer will be so bad that these building will need to be demolished.

A one kilometer evacuation seems extreme. I assume dust is the justification for that, but surely you could just tell people to close their windows if they're not in range for falling debris.

And where are 3.14 square kilometers worth of people supposed to relocate themselves to while waiting for the building to fall? Do hotels in Sydney really have that sort of spare capacity? I wonder how many people are just going to ignore that 1km evacuation order.

The building in question is in Sydney Olympic Park, a relatively sparsely populated area far from the city center that used to be industrial wasteland and is now mostly sports facilities (surprise!):

https://maps.app.goo.gl/uZDA8

However, there have been quite a few shiny new apartments going up lately, including this one. And as is the case for almost all residential construction in Sydney lately, the quality tends to be shocking.

Update: the wide evacuation has been cancelled and most tower residents can now return. However, 51 units have been declared structurally unsafe:

https://www.smh.com.au/national/nsw/olympic-park-residents-m...

and most tower residents can now return. However, 51 units have been declared structurally unsafe

How does that work? That's a very strange statement to make. They're implying those 51 units may collapse and leave the rest intact...? Even if I wasn't in those 51, I wouldn't go back except perhaps to quickly get some stuff and move out.

That's a good point.

> NSW Police Acting Assistant Commissioner Julie Boon said "an internal support wall failed" in the building.

If one failed, though, is there any reason why others won't?

The article in the Sydney Morning Herald states that they were only allowed back in (and were escorted) to get their stuff and get out.

The 51 figure is saying that the NSW Police believe that those units are structurally unsound, but the rest of the building is still evacuated all the same.

I imagine GP misunderstood one of the article edits.

The building is >300' tall - if it were to fall in any direction, they would need a certain amount of free access. Perhaps that radius is where the 600m came from.
The building is about 100m high. If it were to topple, and then somehow spread debris 500m away in every direction, a safety zone of 1km radius still would have over two square kilometers for “a certain amount of free access”.
Did we just become best friends?
(comment deleted)
Just for context, Sydney is growing by about 100,000 people annually, due to massive immigration from China and India. With this tower having 300 units, and assuming 2 people on average per unit, we would need to build 3.2 of these giant towers weekly to house every arrival...

By 2067, Sydney is projected to reach 9.5 million people from 5.2 million currently, whereas with net-zero overseas migration it would fall slightly to 4.8 million over the same timeframe.

Additionally, Australia's laws on real-estate money laundering are lax, so foreign criminals will dump their ill-gotten cash into Australian real-estate.

Many of these apartment buildings are sold to Chinese syndicates, not Australian families, which is why so many of the apartments are tiny one-bedrooms (allowing a cheaper cost of entry). I've walked into some of the sales display offices of one of these developments before, and all of the marketing material is in Chinese.

There are other failings at an institutional level, where building inspections have been outsourced and can now be conducted by private certified individuals, not Government officers.

So in this case excessive immigration is literally destroying Sydney... And the NSW State Government agrees, as they are requesting the Federal Government reduce immigration numbers.

Annecdote: I often find that buildings in Australia vibrate / shake. One that stands out in my mind, there's a shopping center in southern Sydney suburb of Hurstville, at one particular spot, it feels like a short tremblor is striking every 10 mins, to the point where I looked up if anyone else may be concerned. There are a lot of cracks in the concrete, but I think that I've read somewhere that as long as the cracks are vertical, that's not bad. However, I'm somehow not convinced that this building would survive should a small real earthquake occur (rare for Sydney, but there was a Newcastle one in recent memory).
Also anecdote: I've lived in 3 different Australian states over 30 years and have never once felt the ground or a building shake. This is not an "Australia" thing.
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The Hurstville shopping centre is right above a train station; Australia is largely earthquake free.
I used to work on the 7th floor of the building at 1-5 Railway St, Chatswood. Sometimes at around 5pm the building would shake subtly but noticeably, we theorised it was from the trains passing underneath.
> However, I'm somehow not convinced that this building would survive should a small real earthquake occur (rare for Sydney, but there was a Newcastle one in recent memory).

The last major earthquake we had in Australia was in the 1989 (and was the 5.6 Newcastle one you mentioned). Since then there have only been 15 earthquakes, many of them less than 4th magnitude. A major earthquake almost 30 years ago is hardly recent. We're in the middle of a tectonic plate, earthquakes are extraordinarily rare.

I am a civil engineer, preparing my thesis for a masters in geotechnical engineering, and unemployed. Last job i had was with a precast crook employing chinese designers and workers. I was forced to work as a draftsman, because I could not get a job as engineer. I don't give two cents for the apartments they are building, and I will comfortably move out of sydney once I get my masters degree. That's the sole reason I am in Sydney. I may even contemplate the possibility of moving overseas, Australia is becoming toxic for professionals.
That's what you get for living at the godforsaken end of the world. Y'all have imported a third world mentality during the last two decades... A bit like the US.
Reading a lot of the comments here about poor quality of new construction have resonated with my own recent experience: I left a luxury high-rise in Chicago that had been built within the last ten years. The building was a later addition to a retail building which contained restaurants and shops. Shortly after moving in, I'd come home to find old grease and trash smells or the smell which I can only describe as an old warehouse.

Thinking it was just residual odors, I would clean and re-clean and later installed a couple of hepa portable filtration systems but the odors remained. Started looking around only to find there was little to no sealant around openings for the sprinkler systems, or underneath the sink unit/washing machine, or any of the flooring etc.

Because the building was pressurized, the odors from the grease traps and/or trash units deep below would come in through even the wall sockets. Mind you, this wasn't every day but regular enough to be very unpleasant. Similar complaints from other residents about cigarette odors coming in their apartments but building management would never be able to trace down issue and would just have restaurants empty out grease traps. All this for an apartment I spent nearly 3,000 a month for. My advice to others is to be very skeptical of any new buildings no matter the location and to be very sure you know what you are getting into.