2 July 2014 — One of many bonuses of the high-level Green Star office for the Australian Taxation Office in the Victorian-NSW border town of Albury was the boost the project gave to the sustainable construction capacity of the area’s building trades.
Doma Group, the developer/builder, also likes to say the 5 Star Green Star Design and As Built building, which also has a 4.5 NABERS energy rating, has been future-proofed by intelligent building design, or “value engineering”.
The six-storey office building is located on a former at-grade car park. In an arrangement with the site owner, Albury City Council, a 500-car multi-level carpark was constructed and the balance of the site used for the building, on which the ATO took out a 15-year gross lease prior to construction.
The ATO specified the ratings outcomes but, according to Gavin Edgar, Doma manager of development, based at the company’s Canberra headquarters, the building’s actual performance is between 4.5 and 5 star NABERS, due to the inherent thermal and energy efficiency performance of the base building.
“We have a proven formula for achieving NABERS ratings, and it is to get the building fabric right,” Edgar says.
“We spend money on the building fabric. If there is one thing we know about from developing office buildings in Canberra, given how cold the winters are, it is how to design and build to prevent air leakage.”
The curtain wall façade system for the ATO office has been designed to manage the rate of infiltration through the facade, which is something Doma had thoroughly analysed with the consistent 5 Star NABERS performance on the completed 46,000 square metre Sirius Building Project for Department of Health and Ageing in the ACT.
Double glazed integrated glazing units were used for the curtain wall and fabricated offsite as there was a degree of uncertainty about the air leakage of locally available window wall style systems.
Like Canberra, Albury is also prone to extremes, with an average minimum July temperature of 2.7 degrees Celsius and summer days often hovering up around 35 to 40 degrees.
“It’s pretty simple really – if the mechanical system has to work harder to compensate for air leakage there will be increased energy use. So we are trying to get an airtight fabric when we build, because mechanical systems are the big energy user,” Edgar says.
“Many builders just think of doing the cheapest façade and don’t consider the long term benefits of an increased capital investment in curtain wall style systems.”
Because Doma is a developer/builder, Edgar says the company would prefer to outlay the budget towards an excellent building envelope to guarantee a minimum 4.5 NABERS rating for the Commonwealth long term rather than use lower capital options and increase the builder’s profit margin. This approach also enables them to extract greater value out of the mechanical design, as well as gaining a substantial number of Green Star points for having a high performance facade.
“So you get a win on NABERS and a win on Green Star,” Edgar says.
Other Green Star projects
Doma has developed five previous Green Star projects in Canberra, in addition to other commercial, hospitality and major residential projects including Hotel Realm Precinct, Department of Human Services Headquarters, Burbury Hotel and Dockside Apartments Kingston.
While the ATO building has since been on-sold, there are several ACT commercial office projects leased to the Commonwealth that the group maintains ownership of. Edgar says the understanding of the operational and maintenance phase informs the approach to design and construction.
“All our decisions are made in view of the long term and we are now turning these principles to our newest office development at 18 Honeysuckle Drive in Newcastle.
“Buyers of a project look at the income stream, and a high NABERS rating does help in terms of the sell. We can say, ‘This is the quality of the asset you are buying,’ and there are some informed buyers who are technically minded who will do the due diligence and say to the client, ‘This is a good long term, high performing asset’.
“There is merit in doing it. Energy usage is a big part of the commitment, and in the market there are big penalties in play in terms of value if you don’t get the [high] NABERS rating.”
There is mandatory disclosure of NABERS ratings when a building is sold or leased, and Edgar says the over 2000 sq m Commonwealth tenants in the Territory would not accept anything less than a 4.5 NABERS rating for property they lease.
“In the end the ATO and the Commonwealth were very supportive of Green Star [for the Albury project]
“The key thing was to work with the locals to upskill them so they then understand what you are trying to achieve. The subcontractors were very cautious and tentative when we first came to town. The investment of time our construction manager Drew Matthias gave people won them over.
“In the end, 80 per cent of the work on the project was done by Albury locals, and only the specialists we needed came from elsewhere.”
This included the Canberra concrete pumps and crew, as no local pump of sufficient boom length was available, the curtain wall team delivered by Yuanda, and the project management and site management team, which were relocated to Albury during of construction.
How to source the right skills subbies – the BER helped
The project started in March 2011 and was completed in October 2012, with the 5 Star As Built Green Star rating formally awarded in April 2014.
Before work commenced, Doma personnel made numerous visits to Albury to understand the subcontractor market, before engaging in a very structured procurement process.
“We found there were a lot of highly skilled subcontractors down there who had been upskilled in Commonwealth procurement processes by the [Building the Education Revolution] program,” Edgar says.
To create a legacy of future green building skills, during the project the construction team undertook a series of initiatives with the local TAFE to show the students techniques that hadn’t been used in the area before.
Canberra work helped develop skills base
Doma currently has eight ACT projects in progress, including residential and serviced apartment projects, hotels, and mixed-use developments with commercial office space, and a mixed-use project in Newcastle.
Edgar says Doma – and the Canberra market – were early adopters of Green Star construction, and have developed a thorough understanding of what it takes to meet the requirements.
“Our guys on sites have a proven formula, they hold Green Star meetings on site with all the subcontractors and suppliers. There is a very good skill base around Green Star in Canberra,” he says.
“The reality is that Green Star has done great things for the industry, and a lot of those things are now adopted as the norm. That’s why I like focusing on NABERS, and I think that’s where the [new Green Star] performance tool is heading.”
Some of the design and construction approaches, which comprise the “new normal”, include drain down for fire services to conserve water, the use of low VOC paints and carpets, and the inclusion of bicycle and cyclist change room facilities.
These are things that are now incorporated as standard into all the company’s projects, whether they are aiming for a Green Star rating or not.
“Clients are getting a lot of Green Star-type elements inherently now in their briefs. It has also impacted on suppliers and manufacturers, for example, it has changed the way carpet manufacturers in Australia make carpet,” Edgar says.
“It was a case for manufacturers of ‘adapt to Green Star or die, fellas’ and particular manufacturers did have to go away and find ways of delivering the required products.
“People now say it’s easy to get Green Star ratings, and that’s okay. We’re already changing how tenants lease space; it’s no longer the norm that the executives get the car space for example. When you stop and think about how it was five to 10 years ago, what we were doing then and what we’re doing now, it’s a fabulous achievement. The Green Building Council deserve all that credit.
“The question is, where to go next?”
One of the areas Edgar wants to see progress is in the reduction of packaging waste.
“Have you ever noticed how much packaging is produced by airlines to give you a tiny little snack? Even the major supermarket chains now sell fresh produce in wrappers. The same trend is happening in the construction industry. So one way to tackle carbon emissions and landfill is to get smarter about what and how we package things. That to me is the next big industry challenge,” he says.