WSP Africa achieves two 5 Star Green Star ratings for new Group Five Head Office

WSP in Africa is thrilled that the new Group Five head office has achieved both a Design and As Built 5 Star Green Star rating from the Green Building Council of South Africa (GBCSA). 

The building, located at the Waterfall Estate in Midrand and developed by ATTACQ, received the award in recognition of the environmental sustainability of the building.

The project came about after Group Five made the strategic decision to consolidate all its offices into a new head office and approached WSP to be their sustainable design and building consultants. Alison Groves, Sustainability Consultant, WSP Africa's Building Services, says; “As the sustainable design consultants for this project we were involved with, and oversaw, all crucial elements of the project related to the sustainability of the building. From the schematic design stage, right through the construction phase, to the comprehensive reporting and handover, we helped Group Five to ensure that the building reflects the company’s commitment to environmental sustainability.”

Construction of Group Five’s new 24 000m2 head office started in October 2012. The building was awarded a 5 Star Green Star SA Design certification in 2013 under the GBCSA’s Office v1 Rating Tool. Once construction was completed a comprehensive assessment was undertaken, and in February this year the building was then awarded a 5 Star Green Star As Built Certification under the Office v1 Rating Tool of the GBCSA.

Indoor environment quality

The primary role of a sustainable building is to provide a comfortable and healthy environment for the occupants of and visitors to the building.  To that end the building has been designed to achieve a minimum 150% improvement on required fresh air rates and to ensure good quality air for all office usable areas. In addition, CO2 sensors provide constant air quality readings to the Building Management System (BMS) which will automatically adjust fresh air rates should CO2 levels rise. 

Additionally, the building has been designed to combat daylight glare, while 80% of the office’s usable areas have access to an outside view. Internal air quality is preserved by the use of low volatile organic compounds paints, carpets, and sealants, and dedicated tenant exhaust risers extract printer fumes at the source, reducing the build-up of harmful indoor pollutants.

Energy and water ecology

“It is important that energy savings are achieved without inconveniencing building users or relying on individuals to take responsibility for energy saving. Occupancy sensors are one example of how automation can realise significant energy savings in a building.  Energy meters are extensively used to monitor energy use and identify unusual or excessive consumption.  This is an important mechanism to manage the building, and optimise operating schedules. Group Five also took the decision to install ammonia chillers which operate at higher levels of efficiency to conventional chillers. Additionally, a thermal storage system has been provided to reduce peak energy demand on the national power grid,” says Groves.

In terms of water, low flow rate fixtures and fittings were installed throughout the building. These fittings restrict flow, but do not impact on comfort and utility. Further water savings are achieved by capturing rainwater for reuse in irrigation and sanitation. Water meters have been installed throughout the building which continually monitor all major water usages and aid in early detection of water leaks.  The project elected to use air cooled heat rejection for the ammonia chillers, removing a huge water burden from the operation of the building and ensuring air conditioning resilience in a potentially water stressed future.  

“The site is positioned adjacent to the Juksei River.  It was vitally important that the project didn’t increase the runoff rate into the river, and to ensure the quality of stormwater leaving the site is free from pollutants.  To this end, the landscape and stormwater management systems were designed to work together. Two large attenuation dams were built to reduce and infiltrate stormwater.  The dams themselves form important features in the landscape and provide a habitat for wild life and birds,” says Groves. “The bulk of the landscape has used indigenous plants that are well suited to survival without irrigation. These plants are more resilient to local pests and as a result require fewer insecticides and artificial fertilisers in order to thrive.  Additionally, the gardens planted between the wings of the building use drip irrigation and are regulated by soil moisture sensors, where these areas also predominately use rainwater for irrigation.”


The project provided the minimum parking bays as required by the local authority. In addition, five percent of these bays are designed for motorbike parking and a further five percent are reserved for fuel efficient vehicles. The Waterfall Estate has numerous bicycle routes and is designing the precinct with “complete roads”.  Bicycle storage facilities are provided, as are showers and lockers. As attitudes to bicycle commuting  change, Group Five will have the facilities in place that will allow building users to make that choice more easily.

“The site is currently served by the Sunninghill Gautrain bus and we anticipate that, as development increases in the vicinity, the public transport offering will also improve. This will continue to create access to alternative means of transport for the building’s occupants,” adds Groves.

WSP also worked closely with the project team to ensure the materials used at this site were in line with sustainability requirements – and that overall the greenhouse gas emissions associated with the operational phase of the Group Five Head Office were reduced as far as possible. The team worked closely with Group Five in the 12 month handover period, which included monthly monitoring, quarterly reporting and a full re-commissioning at the end of the project.

“As a construction company, Group Five sought to be on the forefront of sustainable design – bringing best practice initiatives into their very own building. The building is a great example of what can be achieved when partners who share a passion for sustainable design meet,” concludes Groves.