The Challenge
The Pixel Building is a four-storey commercial development located on the corner of Queensberry and Bouverie Street, Melbourne. It is the first structure completed as part of the greater Carlton United Brewery site redevelopment and was designed to create a statement that sets the standard for future development projects. The developer’s brief for the building required it to be carbon neutral and achieve a six star green rating from the Green Building Council of Australia as well as green accreditation from LEED(UK) and BREEMA(USA).
Water sensitive urban design features in The Pixel Building are critical to these objectives. These features include: vacuum toilets, a rainwater harvesting and treatment train, an anaerobic digester and reed beds for processing of greywater and for thermal cooling of the building.
With these innovations the developer has achieved a leading global position in construction of sustainable commercial buildings.
The Project
The Pixel Building incorporates a combination of innovations to achieve high Green Star Rating and balance greenhouse gas production.
The vacuum toilet system uses one litre per flush compared to six litres for a standard system. Vacuum systems are mainly used in ships and airplanes. For this innovative first installation in an Australian commercial building the chosen system also required standards compliance verification and certification.
Rainwater is used for all internal water requirements and is collected through a roof garden and reticulated to a storage tank in the basement of the building. The harvested rainwater is treated using membrane filtration technology to potable water standards. Additionally four mains water taps were installed as an alternative source of drinking water.
Internal greywater use is disallowed under EPA regulations applying to commercial buildings of this size and the energy requirements for greywater recycling were also found to be disadvantageous to the overall green star rating objectives. In The Pixel Building, filtered greywater is piped to cooling reed beds where the quantity is reduced and from there any excess is discharged to council stormwater facilities.
Blackwater from the toilets and kitchen facilities is collected in an anaerobic digester at the base of the building. Methane produced from this waste is used to generate power for the building’s hot water system. The waste sludge produced from the anaerobic digester is discharged to sewer under a trade waste agreement. This agreement was a new step for the water authority as well and involved extensive learning and consultation.
The Outcome
With a unique combination of water and energy saving innovations, The Pixel Building has achieved the highest green accreditation ratings from Green Building Council of Australia, LEED(UK) and BREEMA(USA). Construction pushed the boundaries of regulations and provided the developer with valuable experience in green commercial building construction which can now be applied to larger development projects.
