The Atholl Towers office development, located in Sandton, Gauteng, was awarded a 5-Star Green Star SA Rating by the Green Building Council of South Africa (GBCSA) this month.

Engineering Firm Aurecon was commissioned by property services company ALW Estates to provide environmentally sustainable design (ESD) services for the project, which exceeded the initial Green Star ambitions for the building by incorporating a range of innovative sustainable features.

Located between Katherine and Patricia streets, Atholl Towers was developed in two phases. The first phase was completed in 2011 and comprises a 4 500 m2 office building for Volkswagen Group South Africa’s sales and consists of 10 211 m2 of office space and 480 parking bays, and five basement levels.

Aurecon ESD consultant Marni Punt says the building is a modern, iconic design with open concept spaces. Some of the noteworthy aesthetic features include full-height façades, frameless glass and overhanging elements that create uniquely framed views of a shared public outdoor area between the two phases.

“Aurecon’s ESD team worked closely with project consultants to create an energy- and- water-efficient building that meets the sustainable development needs of the client. For example, the frameless, full-glass façade is not only energy efficient, but it has a self-cleaning silicone base that ensures minimal maintenance over the coming years,” says Punt.

Some of the other energy efficiency features include improved air conditioning, a central heat recovery system and motion sensor light fittings.

The domestic hot water system is integrated with the air conditioning system to receive recovered heat during cooling or simultaneous cooling and heating modes. When cooling is not required by the air conditioning system, it acts as an air-cooled heat pump to efficiently deliver heat to the domestic hot water system.

Sustainability initiatives that were incorporated include the use of recycled shutter boards for concrete casting, recycled steel components, the use of low-volatile organic compound paint, low-formaldehyde timber and finishes, the smart application of insulation materials and blinds to increase thermal comfort for building occupants, as well as a rainwater harvesting and water conservation systems.

“Atholl Towers marks the first speculative Green Star Rated building for Aurecon and is proud to be involved in this landmark achievement for our client,” says Punt.

Improving the Building’s Efficiency

While the building is efficient in terms of energy and water consumption, the project team took the concept of ‘building efficiency’ one step further when planning the design, layout and building services.

“Building efficiency refers to the efficiency of the usable area to meet functional needs such as tenants’ work flow requirements, office design, and personnel comfort, notes Aurecon ESD consultant Kyra Young.

She adds that the efficiency of a building is dictated by a variety of factors, including the building shape, core location, floor size, leasing depth and corridors.

“These are conventionally addressed in the building design stages but not conventionally carried over to the system design and building operational stages by its tenants,” she explains.

The approach of the Atholl Towers design team was to not only create a highly efficient design but also to ensure this was carried over into the operational stages of the building and maintained by any prospective tenant as well. Efficiency principles were also incorporated into the electrical and mechanical systems design of the building.

Aurecon created a building user’s guide that includes details for tenants, owners and facility managers. Some of the efficiency initiatives include a power grid system that was planned around the building installation design. The power grid and outlets were designed in such a way that tenants will have flexibility in terms of how they plan and use their spaces.

“Tenants at Atholl Towers won’t have to lay a host of data cables after they move into the premises,” explains Young, adding that materials that will be needed to make layout changes for future tenants have been reduced.

“By thinking ahead and merging the building layout, systems and operational design, an innovative and highly efficient building that will have reduced measurable operational costs has been created. Tenant fit-out costs and, most importantly, reduced impact on the environment will be the direct results of these efficiencies,” Young notes.

The project also has an extensive metering system connected to a fully automated building management system. A total of 55 power meters are distributed throughout the building and water meters have been installed for all major water uses.

This is an important building management tool that will assist the facility managers to efficiently manage the building in future. Access to consumption data is provided through the local facilities management PC or a Web browser.

Trend logs will display the history of the water and electricity meter values, allowing usage trends to be accumulated and analysed to identify when and where peaks occur.

“Green initiatives such as these help owners, tenants and building users to understand how sustainable buildings are performing and where improvements could be made. Aurecon is proud to be a part of this noteworthy project,” concludes Young.