The Government’s proposed changes to New Zealand’s earthquake-prone building (EPB) framework represent a significant shift in how seismic risk is identified and managed. While much of the public commentary has focused on the removal of percentage New Building Standard (%NBS) from legislation and the introduction of a new risk-based matrix, the practical implications for building owners are less clear.
How will the proposed system affect different building types and regions, and what should owners be thinking about now, while the legislation is still in draft form? Cathy Thomas, Director and Structural Engineer at Prendos, outlines what the proposed reforms are intended to achieve, why they have been introduced, and how owners can start assessing the real-world implications for their assets.
From fixing the weakest link to reducing life safety risk
At its core, the intent of the proposed changes is simple: a more pragmatic, risk-based system that focuses on life safety, and reduces regulatory burden where it doesn’t make sense.
Cathy sums it up: “The main change is it focuses on life safety.”
That might sound like an obvious outcome to strive for, but the way the existing system has been applied in practice hasn’t always reflected that goal. Under the current approach, a building’s overall %NBS is governed by the weakest element. As Cathy explains, that can create outcomes that don’t line up with real-world safety.
“You’re looking for the lowest percentage element, but what does that mean in terms of the entire building’s safety? Sometimes not a lot.”
She gives a typical example:
“There might be one connection of a concrete beam that’s reducing the %NBS, but I wouldn’t expect the whole building to collapse because of it, so the %NBS doesn’t really relate to the safety of the building as a whole.”
In other words – the rating can be driven down by something that may be important, but not necessarily the thing that controls collapse or major life-safety outcomes. That’s part of why the reforms are aiming to bring the focus onto risk and consequence, not just a number.
What the proposed changes are trying to achieve
The proposed direction is to move away from using %NBS as the legislative trigger and instead use a risk matrix based on factors like higher-risk earthquake zones, building type and height, and whether it’s in an urban centre or less populous location.
“The shift is going from ‘everything could be a risk’ to ‘just high-risk buildings’”, says Cathy.
One way to think of it is that the system becomes less about dragging every older building through the same process, and more about targeting genuinely vulnerable building types in places where seismic risk is higher, and consequence greater.
Which buildings will fall under the new system?
Under the current approach, almost any building constructed before 2004 can be swept into the EPB net, making every building pre-2004 a potential risk.
The proposed system is far more targeted. Rather than treating all older buildings as potential problems, it focuses on building types and locations that are more likely to pose genuine life-safety risk in an earthquake.
In broad terms, the buildings most likely to fall under the new framework are:
- Unreinforced masonry (URM) buildings, particularly in urban centres where falling façades pose a higher risk to the public
- Heavier construction buildings, typically reinforced concrete buildings of three storeys or more, in areas with higher earthquake risk
- Buildings with high occupancy or public exposure, where failure would have more serious consequences
By contrast, many lower-risk building types – particularly low-rise reinforced concrete buildings in lower-risk regions – are likely to fall outside the formal EPB system altogether.
As Cathy points out, this aligns much more closely with real-world performance.
“A single-storey reinforced concrete building has never fallen over in any of these earthquakes.”
For owners, this shift helps separate “buildings that must be addressed” from those where seismic risk can be managed through targeted upgrades, monitoring, or market-driven decisions rather than mandated timeframes.
Why this is happening (and why building owners should care)
Cathy points to a key issue building owners have felt for years: the cost and liability of seismic assessment and remediation can be out of proportion to actual risk – especially when owners are effectively pushed toward increasingly detailed assessments.
“Seismic upgrades have become highly theoretical, which makes it really difficult when you’re taking legal responsibility for it, and why it’s so costly. What engineer wants to stick their neck out?”
For owners, the practical consequence has often been spending significant money on analysis and upgrades that may not meaningfully improve asset value – or may be driven by legal defensibility rather than the highest-value safety outcomes.
If the reforms land as expected, Cathy says it will be a huge win for property owners, who will be able to choose to invest where it delivers the best value.
“Property owners can spend their money on upgrades more in the way they want. They’re not going to be forced down the path of really costly DSAs.”
%NBS won’t vanish overnight – if at all
Even if %NBS is removed from the EPB system as a legislative trigger, Cathy’s view is that market and commercial drivers won’t disappear.
“Lenders and insurers are not going to stop asking for an ISA [Initial Seismic Assessment]. It is a measure of risk for them”, Cathy says.
She also flags tenant expectations – particularly government.
“Government tenants have all insisted on having over 70% NBS, and Mr Luxon can’t stop them doing that.”
This matters because owners shouldn’t misread the reforms as “no one cares anymore.” Banks, insurers, buyers, and higher-quality tenants will still want clarity about seismic performance and risk – particularly on larger assets.
What to do now
- Don’t assume your obligations vanish. Even if your building falls out of the EPB framework, insurance, lending and tenant due diligence may still require a seismic assessment and a plan.
- Focus on “what governs life safety?” Ask what elements genuinely drive the highest risk, and what doesn’t – this is where targeted strengthening can be both safer and more cost-effective.
- Get ahead of the legislation. The best time to map implications is before the final settings are locked in – especially if you’re planning leases, refinance, upgrades or a sale.
How Prendos can help
Our Structural Engineers can translate the proposed changes into plain English and practical decisions for your building: what’s likely to apply, what the market will still ask for, and what a targeted, proportionate remediation pathway could look like.
At Prendos, adding value to your assets is our number one priority. If you’d like to speak with our Structural Engineers about how they can help you maximise the value of your investments, call us on 0800 PRENDOS, email prendos@prendos.co.nz, or fill in the form below and we’ll call you back.
