With an increasing population and intense pressure on resources, the environment and infrastructure, we want to investigate the growing importance of sustainable construction in Southern Africa. Additionally, we will get into the evolving role of cement mixers and how they can be used to help reshape the construction industry, which should help combat the impact of the industry in terms of carbon emissions and harmful pollutants.

 

We will be looking into sustainable construction methods like rammed earth, cob construction, and greener solutions to conventional cement, as well as exploring a few incredible building designs in South Africa that have taken innovation and sustainability to the next level.

 

The Growing Importance Of Sustainable Construction In Southern Africa

 

According to Global Data, The South African construction market is projected to achieve an average annual growth rate (AAGR) of more than 3% from 2024-2027. This growth is due to investments in transport, energy, industrial, and housing projects. Growth trends and Forecasts for 2024-2029 also show that multi-million-dollar construction projects are taking off all around the African continent, transforming cities to meet the needs of the growing population and making construction the largest sector in Africa.

 

Africa is an appealing destination for many large economies due to the availability of natural resources, inexpensive labour, and investment opportunities in infrastructure. According to The World Bank Population Growth Indicator, Southern Africa experiences an average growth rate of 2% yearly, significantly higher than the global average of 1%.

 

As growth continues across Southern Africa, it becomes increasingly important that sustainable construction practices are implemented. Especially if we want to preserve our rich biodiverse ecosystem and its natural resources for future generations, encouraging long-term goals.

 

As sustainable practices become increasingly popular, along with growing pressure to align with the United Nations Sustainable Development Goals (SDGs), economies that prioritise sustainability are likely to be more appealing to foreign investors – encouraging tourism and enhancing their standing in the global economy.

 

 

The Environmental Impact Of Construction

 

As populations grow and technology advances, infrastructure development, including the building of roads, hospitals, schools, and energy systems, plays a vital role in meeting the needs of our societies. However, with this increase in development, there are severe environmental consequences that need to be considered.

 

Habitat destruction: Construction requires space, and this means converting natural landscapes like forests, wetlands, and other ecosystems into built environments, which could be a significant threat to biodiversity. The destruction of ecosystems means the loss of habitats for a variety of different species that occupy these spaces. For this reason, it is crucial to take steps to safeguard these diverse habitats around us.

 

Water, air, noise, and soil pollution: According to the latest research by construction blog Bimhow: the construction sector contributes to 40% of drinking water pollution, 23% of air pollution, and 50% of the environment pollution from landfills. Construction activities like chemical contamination from cleaning agents and construction materials, as well as sediment runoff and erosion, and interfering with natural environments which have natural water filtering systems negatively impact healthy soil and our access to clean drinking water.

 

While these numbers may appear distressing, many courses of action can greatly reduce these environmental issues. As we venture into the future, it becomes increasingly important to proactively analyse construction practices, and opt for greener options wherever possible. Fortunately, as the demand for a greener future grows worldwide, we are seeing more sustainable building solutions being implemented to help mitigate the environmental effects. Let’s get into a few of them.

 

Sustainable Construction Practices

 

Although infrastructure development may be necessary, we should aim to achieve a balance between progress and environmental protection. While cement mixers are not inherently ‘sustainable’, the way we choose to use them can contribute to more sustainable construction practices. Below are a few eco-friendly cement mixing techniques which the construction industry is making good use of:

 

1. Using Sustainable Materials

 

According to the Princeton Student Climate Initiative, concrete is the most consumed product in the world after water. The use of cement dates back roughly 5000 years and can be seen in many ancient civilisations, such as the Romans, Mayans, and Egyptians. Traditional cement production, however, differs from that of our ancestors in that we rely on Portland cement. The creation of this modern cement is the most carbon-intensive part of the concrete process. Here, we will explore a few alternate materials which can be used in the production of cement.

 

Utilising Recycled Materials: Construction leaves behind a lot of waste, however, wasted materials such as glass, plastic, and crushed concrete can be reused and combined instead of having to quarry for unspoilt sand and gravel. Cement mixers can be used to combine the recycled materials with a sustainable binder.

 

Creating Sustainable Cement Binders: The use of Clinker in traditional Portland cement is a major contributor to high C02 levels. Low Carbon cement requires less clinker by using alternative binders such as lime-based and earth-based binders. There are also new, innovative binders which are being investigated such as the use of seaweed, recycled plastics, and even bacteria.

 

Green Cement: A better alternative to traditional Portland cement is green cement, also known as sustainable cement, which boasts 90% lower carbon emission rates. Green cement is created using recycled Portland cement and incorporates supplementary cementitious materials (SCMs) such as slag or fly ash, which require less heat and gas during production – often creating a stronger material than traditional cement.

 

 

2. Optimising Material Usage

 

Precise Mixing: There tends to be a lot of wastage in the construction industry, to prevent this issue, it’s important to use various measuring tools and scales to ensure you are creating the exact amount required for your mix.

 

Minimised Water Usage: Water is a critical component in the creation of cement, it is important to use water wisely during this process to reduce wastage and to ensure the best performance of your cement product. Techniques like curing blankets and fogging will help retain moisture, reducing water consumption and wastage.

 

Repair And Reuse: Instead of demolishing and rebuilding, aim to repair existing concrete structures, wherever possible, to reduce the use of new materials.

 

Reusing Leftover Materials: Leftover mortar or concrete can be used for tasks like patching or grouting, and a variety of other DIY projects like benches or stepping stones.

 

Responsible Waste Management: As a last resort, dispose of leftover materials responsibly. This means finding suitable disposal facilities and adhering to local waste management regulations. Better yet, see if any local building retailers, landscaping companies, or community groups will accept your unused concrete for their projects.

 

3. Using Sustainable Techniques

 

When we look back at ancient construction techniques in Southern Africa, we find natural resources were used to create aesthetically pleasing designs that were built to last. We can use this traditional wisdom and adapt it to modern techniques to create an infrastructure that respects the needs of the human population, as well as that of the natural environment.

 

Creating Rammed Earth Walls: This technique involves the use of locally sourced ingredients such as soil, chalk, gravel, or lime, to create walls that provide wonderful natural insulation and require very little energy – they are also known for their durability and low maintenance. What’s more, the earth used in the production of these walls absorbs and stores carbon dioxide.

 

Cement mixers can be used in the construction process to mix the earth, stabilisers, and other native ingredients to create a well-balanced mixture. Using the right mixture of ingredients is important to ensure the strength and stability of the wall, cement mixers can provide increased control over the ratio of the mixture.

 

Building Cob Houses: The cob mixture combines sand, a fibrous organic material (typically straw), and clay with no additives or chemicals needed. Cob is porous, so it can withstand heavy rains while also being fire resistant. The thick walls created with cob provide insulation and help regulate indoor temperature.

 

For larger cob projects, like commercial or community-based installations, using a cement mixer can drastically speed up the process. Just like in rammed earth walls, cob is most effective when it has a consistent and homogenous mix, which can be achieved with the use of cement mixers.

 

 

Examples of Sustainable Buildings in South Africa

 

These awe-inspiring buildings across South Africa are all vastly different in their approach to sustainability, they have either used eco-friendly materials, repurposed old structures or have been inspired by biomimicry to create a design that uses fewer resources.

 

The Discovery Head office- Johannesburg, South Africa:

 

This incredible building is proof that it’s possible to create a large, high-performing modern building with a minimal impact on the environment. The Discovery Head Office is one of the most sustainable buildings in the country and was awarded a 6-star green rating by the Green Building Council of South Africa (GBCSA). This building was constructed using recycled and locally sourced materials wherever possible. Its insulated concrete panels and double-glazed windows help to keep the space cool in summer and warm in winter, reducing the need for energy-intensive heating and cooling systems.

 

The Silo District- Cape Town, South Africa:

 

This series of buildings was repurposed from old grain silos into a luxurious hotel, apartments, art museum, office, and retail space, and it has become one of the most iconic buildings in Cape Town. This unique building proves how we can save resources by repurposing existing structures.

 

The Eastgate Centre- Harare, Zimbabwe:

 

This magnificent creation was inspired by the efficient ventilation system of termite mounds, which efficiently regulate temperature and humidity. The architect wanted to achieve energy-efficient climate control, the result, a unique, low-energy, and resource-efficient design that can adapt to local weather conditions.

 

About BS Commercial Power

 

We are a Cape Town-based company supplying a vast range of tough, high-performance tools and machines, from cement mixers to plate compactors. Intended for individuals and companies in the construction, forestry, agriculture, and a variety of other sectors across Southern Africa. At BS Commercial Power, we believe that sustainability encourages innovation – we are always on the lookout for ways to be more innovative and stand out as leaders in high-performance commercial equipment in Southern Africa.

 

 

With rising concerns about climate change, it’s more important than ever that we explore and adopt sustainable practices to create greener spaces for a healthier and happier planet. We hope this article inspired you to look out for upcoming projects and see how you can educate your teams and implement greener construction practices into your work. Remember, even small changes can make a big difference. Feel free to reach out to our experienced team to assist you in finding the right equipment for your next project.