How NABERS is Shaping the Future of Sustainable Buildings
Our Senior Sustainability Consultant, Jaime Oliver, shares her thoughts on the evolving nature of sustainability certifications, the growing influence of NABERS UK, and what architects and developers need to know about its role in real-world building performance.
What is NABERS?
NABERS is a certification that measures the operational energy use of commercial office buildings. Unlike other certifications that focus on design, NABERS is based on actual metre data, making it a more accurate reflection of a building’s real-world performance.
It uses a star rating system, typically ranging from three to six stars, to indicate how efficiently a building operates. The goal is to help building owners track performance over time, maintain their rating, or improve it by identifying and addressing inefficiencies.
In a nutshell, NABERS provides a reliable way to assess and improve the energy performance of office buildings.
How long has NABERS been around?
NABERS is fairly new in the UK, but it’s been around for quite a while in Australia—it actually started there and has been widely used for years. New Zealand also adopted it before it made its way over here.
When it first arrived in the UK, it was under BRE but has now been recently taken over by CIBSE. So, in the UK, it’s still in its early days.
Do you think NABERS will help our clients?
Certainly, I think it’s a really useful tool—especially for developers with an estates team or clients who will actually be occupying and managing their own buildings.
“The key thing with NABERS is that it’s based on a full year of operational data, so it gives a true picture of how a building is performing, rather than just predicting it. That means it’s less relevant for clients who are simply developing and selling on a building, as they can’t guarantee a NABERS rating until that data is collected. This is where the Design for Performance assessment becomes beneficial, the design for performance assessment allows developers to commit to designing, building and commissioning to achieve a target NABERS energy rating, allowing tenants or building owners to then carry out the NABERS Energy rating.”
But for those who will be running the buildings long-term, NABERS fills a real gap in the market. Traditionally, everything has been focused on design once a building is handed over, that’s it—but NABERS brings accountability to the operational side, which is a game-changer.
What are the main benefits?
The biggest benefit of NABERS is that it’s based on real operational data. That means it helps clients spot inefficiencies, identify where things aren’t working as expected, and ultimately reduce operational costs. Plus, it also benefits the people using the building, helping to improve comfort conditions by ensuring things like heating, cooling, and lighting are performing as they should.
The key difference between NABERS and other certifications, like BREEAM, is that NABERS looks at actual performance, while BREEAM is based on design intent. There’s something called the ‘performance gap’—where a building is designed to meet certain sustainability targets—but once it's in use, real-world factors come into play. You can’t always predict how people will use the space, how long they’ll leave lights on, what temperature they’ll set the thermostat to, or how efficiently the building will actually run.
That’s where NABERS comes in—it bridges that gap between predicted performance and real-world operation. But both NABERS and BREEAM have their place; BREEAM helps set ambitious sustainability goals from the outset, while NABERS ensures those goals translate into real, measurable outcomes.
Why is NABERS only being used for offices spaces within the UK currently, and no other sectors?
In Australia, NABERS is used across multiple sectors, but in the UK, it’s currently limited to commercial office buildings. The main reason for this is likely that NABERS is still relatively new here, so there may not be enough benchmarking data yet for other building types.
Because NABERS ratings are based on actual energy use, there needs to be a solid dataset to compare against - without that, it’s difficult to accurately determine whether a building is performing at a three-star or four-star level, for example. In Australia, where NABERS has been established for much longer, they’ve had time to collect and refine this data across different sectors.
That said, this is just my take on it, and it would be interesting to see if CIBSE plan to expand NABERS UK across other sectors in the near future.
In terms of the UK’s Net Zero goals, do you think NABERS is going to help much?
Definitely, it’s already being closely aligned with the new UK Net Zero Carbon Building Standard (UKNZCBS), which is a big step in the right direction. If a building is aiming for a NABERS rating, it’s likely also working towards meeting net zero targets, which makes it a really useful framework for clients looking to future-proof their buildings.
Since NABERS focuses purely on operational energy, it directly supports net zero strategies by ensuring buildings aren’t just designed to be energy efficient but are actually performing that way in real-world use. And that’s key—because when it comes to net zero, it can’t just be about ticking design boxes, it must be about making sure energy use is as low as possible in practice.
It’ll be interesting to see how things evolve over the coming years as net zero standards continue to develop. With the push towards stricter carbon reduction goals, we’ll likely see more refinement in how these frameworks work together. But NABERS is already playing a valuable role in driving real performance improvements.
What’s your process when you work with a project team on the sustainability side of things?
Early engagement is key, that’s always our focus. The sooner we’re involved, the more we can help shape the sustainability strategy in a way that’s actually achievable. A client might come to us and say they want to pursue NABERS, but if we look at the design and realise they won’t score well, it’s much better to address that early rather than further down the line when changes are harder (and more expensive) to implement.
“Collaboration is about having those conversations upfront, discussing what certifications or sustainability targets make the most sense for the project, what’s realistic, and what can be done to improve performance. It’s all about tailoring the approach to align with both the client’s ambitions and what’s feasible in practice.”
Any pain points?
Managing expectations can be a challenge. Sometimes project teams come to us with a plan that, on paper sounds great, but when we look at the M&E strategy, it might not actually align with the sustainability goals they’re aiming for. And if the project is already quite far along, making changes at that stage can be costly.
That’s why we always push for early conversations, it’s much easier (and more cost-effective) to make informed decisions at the beginning than to retrofit sustainability measures later. Transparency is also crucial. We want to work closely with clients to make sure their sustainability goals are realistic from the outset, so they’re getting the best outcome in terms of performance, cost, and efficiency. The sooner we collaborate, the better the results.
Looking ahead, how do you see sustainability frameworks and regulations evolving within the building sector?
There’s definitely a shift towards using real operational data—meter data, rather than just predictions on paper. NABERS is already doing that, and the new UK Net Zero Carbon Building Standard (UKNZCBS) is following suit. I think we’ll see more frameworks moving in that direction, where buildings aren’t just assessed at the design stage but are actually measured on their performance in use.
Right now, with certifications like BREEAM, SKA, and even WELL, you do all the assessments, testing, and compliance work before operation—but once people start using the building, things naturally evolve. Occupancy patterns shift, energy use changes, and a building might not perform exactly as predicted. So, I think there’s going to be a stronger push to evaluate buildings over time and ensure they’re working as intended.
That said, it’s important that frameworks don’t just become a box-ticking exercise. It’s all about striking the right balance, making sure we’re actually driving sustainability forward without overcomplicating things for clients. The goal is to make it easier, not harder, for them to meet net zero targets, and that comes down to collaboration. If we work closely with clients and project teams from the outset, we can find practical, effective ways to meet sustainability goals without unnecessary roadblocks.
Were there any personal challenges for you when gaining this qualification?
It’s definitely a tough qualification to achieve, but it’s fair and it’s difficult for a reason. There’s a lot of M&E knowledge required, which I didn’t have at first, so that was a challenge for me early on. But the exam is a good reflection of the actual assessment process. Now that I’ve passed it, I feel confident in carrying out assessments because the exam really prepares you for what’s involved.
At CPW, we work closely with our engineers, and there’s a lot of crossover between our specialist teams, particularly between Sustainability and MEP. That collaboration helped me build on my knowledge and develop the skills needed to navigate the qualification process.
Are there any other certifications that compliment NABERS?
I think WELL and NABERS complement each other perfectly. WELL is focused on wellbeing, ensuring the end-users of the building are comfortable and happy, whereas NABERS is more data-driven—looking at the actual operational performance of the building. So, together, they offer the best of both worlds.
That being said, most certifications have some crossover with NABERS, because at their core, they all aim to improve energy efficiency in buildings—that’s what NABERS proves.
When it comes to choosing a framework for a project, a lot depends on location and market demand. For example, when I worked in London, there was a big push for WELL because it was new and heavily marketed. In the Midlands, the market is different, and that trend hasn’t been as strong. Planning requirements also play a big role —BREEAM is often a planning condition, which means there’s less flexibility in choice. Other certifications, however, are more dependent on the sector. For instance, universities often prefer SKA over BREEAM, likely because the Higher Education sector is more familiar with it, and it’s become more of a norm for them.
What’s the usual standard for the commercial sector in the UK?
The City of London have officially made NABERS a planning regulation for office developments, as of last year, so the certification is increasingly gaining momentum. As part of the plans to achieve net zero by 2040, a minimum NABERS UK rating of five stars is required.
However for the majority of the UK currently, I’d say BREEAM. The commercial sector is unique in that most certifications apply to it, so there’s more flexibility in choosing a framework. But if you take warehouses, for example, they’ll almost always go with BREEAM because there aren’t many other tailored options for them. While commercial buildings can opt for various frameworks, BREEAM remains the most popular standard across the sector.
What are the advantages of NABERS over BREEAM?
One of the key advantages of NABERS is that it places less burden on the design team in terms of box-ticking and documentation. We, as assessors, take on most of the work, as long as the design has considered NABERS requirements from the start. That’s why early engagement is so important.
NABERS is also more performance-driven. If we’re reducing energy use, we need to focus on the building fabric and M&E strategy—but rather than prescribing rigid criteria like “this must meet that,” NABERS takes a more holistic approach. It’s about making the building genuinely sustainable, rather than just complying with specific checklists. That flexibility can be a real advantage.
Want to learn more about how NABERS and other sustainability certifications can benefit your project? Get in touch with our team today.