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Case study: The secret to sustainability success

Case Study | 15 Dec 2020

NABERS Commitment Agreements: The secret to sustainability success

Standing sentinel on the sinuous Brisbane River, 1 William Street is a catalyst project that reconnected the city to its waterfront, sparked the transformation of Queens Wharf and brought 5,000 Queensland Government employees from 20 different offices under one roof. Dubbed the “Tower of Power”, 1 William Street is a distinctive statement on the skyline that reminds Queenslanders of the hard work that goes on within its walls. Less visible, but just as important, is the commitment to energy efficiency and sustainability that underpinned 1 William Street’s design.

We felt a responsibility to create something that all of Queensland could be proud of – a building that stretched sustainable best practice and took innovative workplace design into the public sector

- Bronwyn McColl, Principal, Woods Bagot

Designed by Woods Bagot, and owned by Cbus Property and ISPT, 1 William Street is a beautiful building to behold.

A glittering façade reflects the aqueous light from the river and the changing colours of the sky. A distinctive sharp chamfer defines the building’s crown, while the splayed rooftop terrace offers panoramic views of the city.

Each of 1 William Street’s 43 levels offers exceptional 360-degree views. Generous floorplates – some up to 2,100 sqm – are flooded with daylight. A unique sky garden and laneway through the core of the building provide both collaborative and concentration spaces.

The building was conceived “from the inside out”, with a full-height atrium supporting a non-hierarchical, inclusive workspace, explains Woods Bagot Principal Bronwyn McColl.

“We thought about the people who would work at 1 William Street first, and then designed an efficient building that would support them,” Bronwyn says.

The walls of glass are windows onto the world that remind the building’s occupants of the communities they serve. At the same time, transparency gives those outside the building a sense of the people dedicating their time and talent to Queensland.

A 5 star NABERS Energy rating was a specific requirement of our tenant, the Queensland Government. But we also signed a NABERS Commitment Agreement so we could promote our design target and establish explicit obligations for our builder. - Adrian Pozzo, Chief Executive Officer, Cbus Property

Pushing the boundaries of best practice

Working just as hard are the mechanical services, innovative façade system, and passive design features that deliver an impressive 5.5 star NABERS Energy rating. That commitment to energy efficiency was embedded in the project before a design was determined or a sod on site turned.

“Often we find the architects are trying to convince the client to pursue a sustainable design, but in this case, our clients wanted to push the boundaries,” Bronwyn explains.

Pushing those boundaries meant setting an ambitious 5 star NABERS Energy target in 2013 – an achievement that was met and exceeded in 2018.

The building’s owner, Cbus Property, has the highest-rated NABERS Energy portfolio of 5.5 stars in Australia. 1 Willian Street’s co-owner ISPT also had strong sustainability mandates, and the Queensland Government had high aspirations, says Cbus Property’s Chief Executive Officer Adrian Pozzo.

“At 1 William Street, the NABERS Commitment Agreement formalised our 5 star NABERS Energy target and added weight to energy efficiency as a key driver of the design.”

What is a NABERS Commitment Agreement?
A NABERS Commitment Agreement is a contract signed by a developer or building owner at the design stage. More than a piece of paper, the agreement outlines a commitment to design, build, and commission a building to achieve a specific NABERS Energy rating. Commitment Agreements can be signed for new builds or refurbishments and across a range of building types.

While the Queensland Government’s clear mandate was an obvious driver, Adrian says several secondary drivers were also at play.

“Being able to promote the NABERS design rating at an early stage of a project can assist in attracting tenants and setting expectations from a design and delivery perspective,” Adrian adds.

A Commitment Agreement can help owners attract blue-chip or anchor tenants looking for space that aligns with their values, but it is more than a marketing exercise. The Commitment Agreement process requires a transparent third-party design review that can uncover opportunities and obstacles to high performance. The result? Building owners routinely report lower operational energy costs and increases to capital value.

It is essential that your building goes beyond setting targets and actually signs a Commitment Agreement contract with NABERS to ensure that all stakeholders can see that the project is following the correct process and the target rating is more likely to be achieved.

NABERS Commitment Agreements by the numbers
- Available for star ratings of 4, 4.5, 5, 5.5, or 6 stars
- Target NABERS Energy rating must be 5 stars or above for office base buildings
- To meet energy efficiency requirements in the National Construction Code, the Commitment Agreement must target 5.5 stars or above.
- 91% of buildings with Commitment Agreement’s met or exceeded their target by their third rating
- 85% of new buildings with Commitment Agreements met their target at completion
- 43% of buildings who met or achieved their target at completion exceeded it by at least 0.5 stars
- 91% of new buildings meet their targets in their first three ratings.

Independent Design Review drives innovation

A NABERS Commitment Agreement may set a project team’s sustainability aspirations in stone, but that doesn’t act as an obstacle to innovative design.

“NABERS didn’t stifle us from creating a beautiful building – it just validated the design process,” Bronwyn explains.

“When you are working with best practice design and a rigorous design process, a NABERS Commitment Agreement supports rather than hinders your ability to deliver the best building.”

An Independent Design Review is an essential step in the NABERS Commitment Agreement process. The review is usually undertaken when the project is 30-60% complete – at a stage when there is enough documentation to make informed judgements while still leaving capacity for changes to the design.

“The Independent Design Review added a level of integrity to the design and a level of comfort to the owner and tenant that there would be no risk to achieving 1 William Street’s required NABERS rating,” Adrian explains.

Adrian points to the collaborative attitude of the project team was a “huge contributor” to the project’s success. “From design input at the early stages to robust design documentation, and tuning and commissioning, the project team was pivotal in us elevating our operational rating to 5.5 stars,” he says.

“I think the most pleasing part of the process was that we were able to deliver a building half a star higher than the NABERS Commitment Agreement design target. Our first certified rating was 5.5 stars and we have maintained that rating since.”

Tower of energy-efficient power

Years on, 1 William Street is still held in high regard as a benchmark of best practice sustainability.

“Many people who work there said the building changed the way they felt about their work – and that they are proud to work for the Queensland Government because of 1 William Street,” Bronwyn explains.

Adrian agrees, arguing that 1 William Street has allowed the Queensland Government to compete with the private sector in the battle for talent. He calls the building an “investment in efficiency”.

“In many cases, the government was leaving old, inefficient, and under-occupied buildings that were unattractive to workers.”

Bronwyn’s advice to other architects starting work on a project with a NABERS Commitment Agreement?

“Embrace the process. A NABERS Commitment Agreement is a benchmark that can help you create a better product for people and the environment.”

NABERS can be a tool to get people excited about a project. There is a real sense of accomplishment when a NABERS rating is achieved post-completion. It’s a tangible measure of success

- Bronwyn McColl, Principal, Woods Bagot & Cbus Property

NABERS Commitment Agreements in five simple steps

  1. Enter a contract: Sign the Commitment Agreement contract and pay the fee. NABERS will send you a counter-signed contract. You will then have a limited licence to promote your target rating (using approved wording).
  2. Design, document, and model: Design the building or space to operate at the energy performance level outlined in your Commitment Agreement. Prepare the model, simulation report, and minimum documentation as detailed in the Handbook for Estimating NABERS ratings.
  3. Secure and submit an Independent Design Review report: Contract a member of the Independent Design Review Panel to assess the project and provide a report. Share your report with NABERS. More information on how is in the Handbook for Estimating NABERS ratings.
  4. Promote your target rating: Once NABERS has approved your report, you have a full licence to promote your target rating. This includes using the Commitment Agreement certificate and logo.
  5. Get a NABERS performance rating: Once your building is operational, arrange for a NABERS Accredited Assessor to carry out a Performance Rating based on 12 months of real, operational energy usage.