Concor worked with developers to push the boundaries of sustainable design and construction, with a 6 Star Green Star SA Office V1.1 (recognised as World Leadership) and a Net Zero Carbon Level 1 Base Building certification imminent at its latest project in Rosebank’s Oxford Parks – the four-storey Ikusasa office block. This is the highest level of the Green Star rating awarded by the Green Buildings Council South Africa (GBCSA).
Its commitment to Zero Harm and sustainability ideally positioned Concor to complete the Ikusasa office block in Rosebank’s Oxford Parks precinct to 6-Star SA Office V1.1 green standards.
According to Concor contract manager Martin Muller, the company has constructed a number of buildings in this development and elsewhere to 5-Star Green Star SA level in terms of the Green Buildings Council South Africa (GBCSA) certification. Ikusasa will be the first one of its projects to achieve a 6-Star Green Star SA Office V1.1 design certification. Green Star certification is an internationally recognised mark of quality for the design, construction and operation of buildings, interior fitouts and precincts.
“Concor’s strict performance strategies to manage water use, energy consumption, process waste and pollution all contribute to upholding critical environmental standards,” says Muller. “In addition to carefully applying our client’s sustainable designs, our quality systems all contribute to the points requirement in the GBCSA rating.”
These included Concor’s application of a comprehensive Environmental Management Plan on site, in line with its ISO14001 accreditation. It also applied a rigorous Waste Management Plan, which saw 70% of demolition and construction waste being re-used or recycled rather than going to landfill.
“We also conducted a hazardous materials survey on the project site before demolishing existing buildings, in accordance with the Occupational Health and Safety Act and other legislation,” he says. “Wherever we found asbestos, lead or polychlorinated biphenyls, these substances were responsibly removed as the law required.”
Annelide Sherratt, head of department for green building certifications at Solid Green Consulting, notes that four key members of Concor’s site team completed the Green Star online course – which helps the team understand and apply sustainable ratings on the project. Sherratt highlights that the Green Star certification focuses on nine categories of sustainability achievement, from management and materials to the reduction of energy use, water and emissions.
“In terms of the materials category, for instance, the Green Star rating rewards developers and contractors for reducing the amount of natural resources used, and for reusing materials wherever possible,” she says. “At the Ikusasa project, Concor reduced the portion of ordinary Portland cement used in their concrete mixes by 30% as an average across all concrete mixes used in the project, and achieved a level of 60% recycled content in the steel requirement.”
Local sourcing of materials also played a role in this category, where Concor sourced 20% of the contract value from suppliers within a 400 km radius of the site, and 10% within 50 km.
In terms of energy efficiency, Ikusasa aims to achieve a Green Star SA Net Zero Carbon Level 1 – by generating as much energy on site as the base building would require. This includes the use of a photovoltaic solar generation system on the roof of the building, producing renewable power. The building’s design and operation enhances energy efficiency by applying sub-metering to track and control the main areas of consumption.
“Any energy uses of 100 kVA or more are metered separately so users can benchmark usage targets and implement opportunities to reduce consumption,” she says. “This impacts on the production of greenhouse gasses and other emissions associated with electricity generated by fossil fuels.”
The data generated by the metering system is captured and analysed by a digital monitoring system for building management, but is also shared with the building’s tenants and visitors on a public display screen – aimed at raising awareness and driving energy-efficient behaviour.
Conserving water is another important element of the building’s environmental performance. This is optimised using options like low-flow tap fittings and dual flush toilets, as well as water sub-metering for uses such as irrigation and bathrooms. Plant irrigation was reduced by 50% using water-wise irrigation methods and smart sensors. Also, the heating, ventilation and cooling system is cooled by air rather than by water.