Building our future

By Maxine Volker

In the last decade, South Africa’s construction industry has taken substantial steps toward going green. November 2011 saw new energy-efficient building regulations come into place, boosting a growing trend of cutting-edge green architecture throughout the country. The implementation of these regulations included a strict set of rules which construction companies had to follow. New buildings are now required to use solar water heaters, heat pumps or similar technologies. It is also now compulsory for walls, ceilings and windows to meet the minimum requirements in insulation in order to minimise heating in winter and cooling in summer. These are just a few of the parameters which have been set out in recent years. They are laid out in the South African Bureau of Standards and are enforceable in terms of the National Building Regulations and Building Standards Act. The regulations apply to all future energy-consuming structures, both residential and commercial. Local authorities are now responsible for the administration of the regulations as well as on-site inspections. Currently, South Africa is one of the global leaders in green building, implementing a number of sustainable practices, methods, materials and technologies.

If we look at environmentally friendly construction as a pyramid, sustainable practices essentially from the base of the structure. The way these practices are put into place set the tone for the eventual outcome. The practice of green building in South Africa is overseen by The Green Building Council of South Africa (GBCSA) which was launched 2007 and works with its membership community in an effort to encourage a built environment in which both people and planet thrive. The GBCSA has developed Green Star SA rating tools, an initiative aimed at providing the property industry with an objective measurement for green buildings and to recognise and reward environmental leadership in the property industry. Each Green Star SA rating tool reflects a different market sector. These include retail, office, multi-unit and residential.

September 2014 saw the launch of the EDGE (Excellence in Design for Greater Efficiencies) rating system. EDGE has been implemented in South Africa thanks to the GBCSA and its partnership with World Bank Group member, the International Finance Corporation (IFC). The primary aim of EDGE is to facilitate a transformation of the property sector in rapidly urbanising countries through influencing design considerations. To achieve the EDGE standard, minimum savings of 20% energy, water, and embodied energy in materials must be met. EDGE has been adapted for the local South African context, especially in light of the SANS 10400 Part XA energy efficiency building code. This code was promulgated for all new buildings in 2011. The total number of green-construction projects certified by the GBCSA has increased by 121% since 2009.

When it comes to going green within the construction industry, the methods and materials used are a vital element. As we move toward efficiency and sustainability, industry experts are utilising new, innovative materials as well as a resurgence in certain age-old materials which have naturally environmentally friendly properties. These days, the list of eco-friendly building materials is extensive and ever-growing. Environmentally friendly or sustainable building materials refer to those that are reused or natural, minimising environmental impact.

The distinguishing factor between building materials that are sustainable and those that are not, is the amount of embodied energy the material has. The term ‘embodied energy’ refers to the sum of all the energy required to mine, manufacture and then transport the material. Ultimately, the lower the level of embodied energy a material has, the more sustainable it is for use.

Wood is one of the most popular eco friendly building alternatives as it is able to provide durable and solid insulation structures. Straw bales are utilised as a renewable energy source because if efforts to keep them dry are put in place, they can last many years. Although an effective alternative, it is important that when utilising this material steps are taken to prevent rodent and insect infestation. Additionally, appropriate measures to prevent damp must also be taken. Sandbag construction, essentially a technology in which bags are filled with locally sourced natural materials, lowers the embodied energy that comes with the manufacturing and transportation of regular building materials. Utilising sandbags requires no cement or binder and also has the advantage of being versatile − the bags can also be filled with rubble, gravel or clay.

Other eco friendly building materials being used in South Africa are recycled steel, mycelium, thatch and bamboo. ‘Hempcrete’, which combines hemp fibre, water and lime which are then moulded into lightweight blocks, has seen massive popularity worldwide as it a renewable building material that can be grown and replenished quickly. Hempcrete has not yet been legalised in South Africa, but efforts to commercialise it are being explored and proposals being put forward to government.

Green building technologies have seen a surge in popularity in recent years. These technologies, which make buildings more sustainable and energy-efficient, are farreaching and having massive impacts on the construction industry. One process which is making leaps and bounds in sustainable construction in South Africa is 3-D printing. 3-D printing, or additive manufacturing, is essentially where 3-D objects are created from a digital file. In the context of construction, 3-D printing is used in a variety of ways. It may be used to create construction components or even ‘print’ entire buildings. The construction industry as whole generates a huge amount of waste and because it is so multidimensional, progress towards sustainability can often be slow. When looking at eco friendly construction as a whole, we know that supply chains in the industry are complex, often resulting in sustainable practices having little impact. There are numerous companies involved in a single construction project. This can make it extremely difficult to ensure a sustainable approach is employed throughout the entire supply chain. This is where 3-D printing comes in. These disruptive technologies have the potential to change the way that products are not only designed, but also manufactured. Basically, they can change the structure of supply chains.

The construction industry, which has been known to impact harshly on the environment, has taken massive strides towards being environmentally friendly in recent years. With a growing worldwide emphasis on the need for climate-change mitigation, South Africa has become one of the global leaders in green building. As built-environment professionals become more inventive and resourceful, eco friendly technologies and methods only seem to be evolving. However, having a lower carbon footprint requires more than simply following a set of procedures. It requires an innovative approach and open-mindedness. We need to look towards the future we wish to build for generations to come, and then implement the strategies needed to sustain it.

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