The South African National Roads Agency Limited (Sanral) has become the first South African parastatal to achieve a Green Star South Africa (SA) rating for one of its buildings, the Green Building Council of South Africa (GBCSA) said on Tuesday.

Sanral’s new corporate head office, in Pretoria, was awarded a 4-Star Green Star SA - Office Design v1 rating. A 4-Star rating is defined as “best practice” in the rating system.

The building, which cost over R100-million and was completed last year, included a “green roof” planted with water-wise succulents, solar-generated hot water for a fresh air heating system and a facade consisting of two layers that increased natural light and views while decreasing heat build-up.

The building also comprised a specialised outer shading layer, or vertical green walling system, which provided essential sun screening. Further, combined with the green roof, the system reduced the urban heat island effect, which was a significant environmental benefit, said GBCSA CEO Brian Wilkinson.

“The Sanral building scored particularly well in the energy and water category - significantly reducing the building’s use of these scarce resources,” he added.

The air-conditioning systems consisted of two air-cooled reverse-cycle heat pump chillers with a combined capacity of about 75% of the peak building-design cooling load.

“Green building offers one of the simplest, most immediate and cost effective ways to reduce human-generated carbon emissions - it is essentially the ‘low-hanging fruit’ - and it is through the efforts made with buildings such as the Sanral corporate head office that South Africa will begin to move towards our commitment of reduced carbon emissions,” he said.

South Africa committed to reducing its carbon emissions by 34% by 2020 and 42% by 2025 below the business-as-usual scenario.

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