Sustainable Solutions for a Two-Tower Building
102 Rivonia Road was constructed to replace EY’s former office space, so a fast-track process was put in place to meet the firm’s strict 18-monthcompletion deadline. The building is situated in a strategic location offering connectivity to major transport links, including the airport.
A plaza has been designed at street level to encourage collaboration and communication between colleagues from different parts of the office complex. In EY’s tower, this collaborative environment is reinforced through the use of criss-crossing bridges above the atrium. The office space has been designed with an activity-based philosophy in mind, providing employees with a variety of amenities and choices of where and how they wish to work. The inclusion of green features such as the green wall in the reception area that reduces noise, improves air quality, and induces a general sense of wellbeing, is central to the design.
We provided electrical design and sustainability consulting on the project. This new development is designed to be 50% more energy-efficient than the average office building offering a reduction in carbon emissions of approximately 130kg of CO2/m2/year compared with a similar building. The use of passive shading systems prevents excessive heat in the office and reduces the need for air conditioning. A solar control glass was used for the fully glazed façade which blocks up to 72% of solar heat by reflecting it to the outside while still admitting an abundance of natural light: this creates a comfortable environment for the occupants. The glass façade also provides 60% of the floor area with a view on the outdoor. Additional passive design strategies allowed us to further reduce the energy consumption while achieving an optimal indoor temperature.
Water consumption was significantly reduced thanks to air cooled chillers and fire systems that recycle used water, and rain water is harvested and used for toilet flushing. The use of fly ash in the Portland cement allowed a 30% decrease in material use, further lowering the carbon footprint of the project.
Presence sensors control lighting to avoid unnecessary usage when the open office space is unoccupied, and spaces smaller than 100 square-meters have individual switches. The objective was to achieve an electricity consumption of less than 2 watts per square meter per 100 lux. These green building design solutions resulted in both towers achieving a 4 Star rating in the Green Star SA rating system.