Construction World February 2016

ENVIRONMENT AND SUSTAINABILITY

This is not only the first Six Star rated green building in Rwanda, but on the entire continent outside of South Africa. WSP|Parsons Brinckerhoff Africa, one of the largest multi-disciplinary engineering consultancies in Africa, has achieved a six star rating for its Nobelia Office Tower in Kigali, Rwanda. > RWANDA’S FIRST six star rated green building

is in its infancy, a local context report had to be developed so as to establish the ground- work for the Green Star and set the appro- priate standards for the climate and environ- ment in Rwanda, as this is to be the standard to which all building projects will be rated. This process required a significant amount of research and assessment, all undertaken by WSP Green by Design, and submitted for assessment by the Green Building Council governing body. However, Naicker comments that under- taking this process also provided the Green by Design team with invaluable insights on the local environment, which was influential to key innovations within this project. Some of the innovative and significant sustainable features of this building include: • Offsetting the importation of building products and related carbon emissions for changing cement, which would normally have been imported from South Africa. Rather these products were substituted for volcanic ash, which is a natural substance and widely available within Rwanda. • The façade of the building contains no glass and rather is made of a polycarbonate material mesh structure that allows plants to grow under it. The objective was to ensure vegetation could grow all over the mesh, thus creating natural shading. In addition to this, the entire façade is manufactured for 100% disassembly – for reuse or recycling. • A sophisticated HVAC system had to be incorporated to dehumidify the fresh air, which will be distributed through hollow core floor slabs, where the air is fed at floor level, displacing the air in the room and extracting it higher up at ceiling level. • Onsite waste management needed to address as all organic waste will be used to create compost onsite – adding ecological value by improving soil, plant growth and biodiversity. • An onsite water treatment system that resulted in a 90% total reduction of water discharge by treating black and grey water for reuse onsite (in irrigation, etc.). • A 430 panel PV installation generating 198 804 kWh/year, which will reduce the peak energy demand of the building by 53,4%. • All usable areas have 100% LED fittings, with intuitive daylight sensors, which can detect how much natural light is available

The Nobelia Office Tower in Kigali, Rwanda, will be a 19 storey tower, of which 16 floors will be dedicated to office space. With a total gross floor area of 11 469 m 2 , the building site is on previously developed land, to prevent urban sprawl. The building is also located within close proximity to commercial, residential, recreational and retail zones. The final assessment for the design of the building is completed, where the project owner is lobbying for funding to go ahead with construction. WSP’s Green by Design team was appointed to this project based on the company’s expertise and reputation as sustainability consultants, as well as its working relationships within the broader industry. Eloshan Naicker, sustainability consultant with the company says, “We are extremely proud of this Six Star rating achievement. At the onset of the project the owner’s brief was to produce a design that would set the bar for green buildings in the country – and we have certainly met the client’s brief.” According to Eudes Kayumba, Green Building Council of Rwanda, “We are so impressed with the Six Star Green Star rating of this project that we are aiming to use the design of the Nobelia Office Tower as the benchmark for all future green build- ings in Rwanda and the wider Central East African region.” The design phase of the project commenced in 2014 and was completed in October 2015 where WSP Green by Design was involved from conceptualisation through every phase of design – finding ways to be innovative and delivering consultation to the project team around Green Star require- ments. Additionally, the consultants devel- oped a high level strategy for the project team and facilitated the implementation, to ensure quality of services could be maintained. “The Six Star rating was not easily achieved, as we had a number of challenges on this project – not least of all developing the rating standards, which first had to be established for a Green Star rating to be possible in Rwanda,” adds Naicker. As the Green Building Council in Rwanda

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and compensate for the difference, as well as occupancy sensors. • Further recommendations were made that no formaldehyde products, or ozone depleting products, be used in the construction of this building, improving the quality of the indoor environment. “Overall, during the design assessment the building achieved a high score for its energy performance potential. This score can be attributed to the reduced carbon footprint and CO 2 emissions that the design was able to achieve. “To achieve a Six Star rating you need to be prepared to push previously conceived boundaries. And, through the collective and dedicated efforts of the project team, not only were we able to achieve the best possible outcome on this project, but we have certainly set the benchmark high for future green building projects in Rwanda,” concludes Naicker.

CONSTRUCTION WORLD FEBRUARY 2016