By Gordon Brown
According to the World Green Building Council the construction sector accounts for up to 40% of waste in landfill sites worldwide, and while this figure may be lower in South Africa construction remains a significant contributor to landfill content. The National Waste Information Baseline Report (DEA2012) indicates that the construction sector is responsible for 8% of all waste generated, although it is unclear whether this number includes the waste from product suppliers during production, which is significant. Importantly this statistic also excludes the ongoing operational waste generated in all occupied buildings, and so is understated.
Construction waste is made up of aggregates (concrete, stones, bricks) and soils, wood, metals, glass, biodegradable waste, plastic, insulation and gypsum based materials, paper and cardboard, a very high percentage of which are reusable or recyclable if separated at source. Currently 16% of construction waste is recycled in South Africa (NWIBR).
Trends and forces for change
The green building movement is being spearheaded by the CSIR and the Green Building Council of South Africa, the latter having set up rating tools that award points for, amongst other green building aspects, resource efficiency for designs which reduce waste.
Construction waste emanates due in some part to inconsiderate design, construction, maintenance, renovation and demolition, as well as supplier considerations such as packaging. Intelligent design and best practices during each phase can significantly reduce waste.
Architects and engineers have a very significant opportunity to affect the waste generated through the life cycle of a building by determining the method of construction and the materials specified. From simple strategies like utilising building rubble onsite as fill for instance, or reusing items from demolished buildings such as wooden window frames, by specifying materials with recycled content, and adopting strategies and building methods geared to dismantling and designed for deconstruction – design affects everything, and with careful planning and consideration given to waste and reusing materials at concept stage, much waste to landfill can be avoided. An example of this is modular construction.
It is also very important at design stage to consider how the building is going to manage operational waste while the building is occupied – sufficient space will be required for recycling storage and sorting, as well as the access to various floors and of course for collection.
At a waste management level, there are a number of best practices to ensure maximum recyclability of materials on site:
- Make this consideration a key performance criterion when appointing contractors
- Set targets for % of waste not to go to landfill (refer to Green Star SA for achievable best practice)
- Have a waste management plan drawn up according to best practice prior to beginning the project(ie. Part of the tender/brief document)
- Have correctly marked skips for certain waste streams
- Ensure that the correct paper work is filed for all items removed from site
- Safe disposal tickets for hazardous waste must be kept
Keep a monthly and overall project reports of all waste and at the conclusion of the project –confirm whether targets are being achieved
There are many great examples of achieving excellent standards in construction waste management, one of these was the first Green Star SA certified project in South Africa, the Nedbank Phase II building in Sandton – in 2008 the contractor was initially concerned about the high standards set within Green Star SA for waste diverted from landfill (30, 50, or 70% of construction waste). By the end of the project, with the good waste management programme they employed, they were surprised at the incredible success – they were able to divert over 90% of their construction waste from landfill. This is a significant achievement, and is replicable across all construction projects by implementing good waste management programmes.
Product and Material Suppliers suppliers have huge potential to reduce the amount of waste going to landfill. Many suppliers could provide their materials to site in a way that requires less or no ‘packaging’, or packaging that is recyclable, and also ensure that their contract with the construction contractors is such that their packaging is returned to them directly for recycling or reuse. ‘Packaging’ is a significant waste source. (Packaging refers to anything that is not the actual material that will be used and left installed on site.) Besides the ‘packaging’ referred to, the product suppliers are also responsible for a significant amount of waste at their own factory or storage houses – the contractors and design team can have a significant influence on the downstream waste impacts by contracting only with suppliers that minimise their waste production and maximise recycling and reuse of waste.
The building in operation
During the course of a buildings life it will require multiple new light bulbs, new carpets and flooring, painting, filling, stripping, windows due to breakages etc. Good building managers and operators can make the necessary effort to separate materials.
The Green Star SA rating tools will reward designers for making provision for separation operations within the utilities area of the building, and building maintenance would utilise these facilities for its waste streams. It is important to have both the space designed to store and sort the waste for collection, but also to have waste management policies in place for the ongoing operation while the building is occupied.
As the market places a greater value on sustainability, products with recyclable content become more sought after. Masonry bricks made from crushed aggregates, tiles made from recycled plastics, are just two examples of products gaining traction.
On the waste disposal side, costs are rising but it remains relatively cheap to dispose of construction waste to landfill, cheaper in fact than general waste disposal which costs R272.00 per ton.
As costs increase so too does illegal dumping, which poses an environmental problem, and municipalities need to consider increasing the penalties imposed on transgressors and to find ways of policing illegal dumping more effectively. Perhaps funds from increased charges for legal dumping can be directed in part to policing illegal dumping.
The construction sector has a massive impact and a commensurate opportunity to effect positive and meaningful change. Through a combination of product design and innovation, building design and methods, and through best practice waste management on site the sector can radically reduce the amount of waste created and significantly improve on the rate of recycling.
Source: Green Building Handbook Volume 6
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The South African construction market is to be boosted by a new 10-15 year project funded by Chinese company, Shanghai Zendai, to build a new city in Modderfontein in eastern Johannesburg. Once compete, the city will include 35,000 new houses, an education centre, a hospital, and a sports stadium and will house around 100,000 residents.
Chinese firm Shanghai Zendai bought the 1,600 hectare plot of land back in November 2013 for R1.06 billion from South African chemical and explosive company AECI and has plans to develop the site into a world financial centre to rival New York City and Hong Kong. The project is forecast to take around 15 years to complete and will provide jobs for local contractors, engineers and other workers in its construction, as well as 100,000 jobs in the new services available upon completion. The new city site is located on the Gautrain route between the OR Tambo International Airport and the central business district of Sandton in eastern Johannesburg, and will soon include a new Modderfontein station to enable easy access.
The transaction to purchase the property was one of the single largest foreign investments ever in South Africa. Shanghai Zendai is a Hong Kong listed investment company that develops and manages property projects in northern China, Shanghai City and Hainan province and hopes that the Modderfontein project will create a new hub for Chinese firms looking to invest in sub-Saharan Africa.
South Africa is the second largest economy on the African continent and the construction sector is set for a boost due to the South African government’s National Infrastructure Plan which focuses investment in energy, transportation, telecommunication and housing sectors. The construction sector experienced a major boost in 2010 when South Africa hosted the Fifa World Cup, but the economic downturn caused a slow down of growth. Recent government focus on infrastructure development has seen a rapid urbanisation in the country and the project at Modderfontein illustrates the significant influence of foreign investment. Foreign investment is one way by which the South African construction industry is overcoming the challenge of cost overruns that many domestic companies face due to the unavailability of funds, the time-consuming roll out of labour, labour unrest, and major project delays.
Key players in the South African construction market should be aware of the upcoming trend towards ‘green’ buildings. In an effort to promote sustainable development, construction companies are increasingly focusing on developing energy-efficient buildings and sustainable construction solutions.
Source: Companies and Markets.com
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The World Population Bureau estimates that the population of Africa will rise from 1.1 billion in 2013 to 2.4 billion in 2050. This means that most of the continent’s economies will have to double in size in the next 36 years.
If that is to happen, then the stock of Africa’s infrastructure assets, including all of its residential, industrial and commercial buildings and power, transport and sanitation systems, will have to double in size. In other words Africa will have to be built again in a single generation.
This will require unthinkable amounts of cement, building materials, construction planning, manpower, products and services to accomplish such a momentous task. And, for this reason, infrastructure investment is providing the platform for the strong economic growth trends that will pave the way for businesses, to explore a number of exciting commercial and business development opportunities in Africa’s construction sector.
The African Construction and Totally Concrete Conferences and Expos will be returning to the Sandton Convention Centre, between 12 and 14 May 2015. These platforms not only facilitate open dialogue but provide a unique opportunity for a diverse group of professionals involved in the transformation and development of the African construction, cement and concrete industries to network, share knowledge, best practices and the latest thinking.
Africa’s only three-storey expo
The audience comprises 600 – 700 key decision-makers from Africa’s construction, cement and concrete industries who attend the conference; and over 6000 mid-to-senior level executives who visit the expo. Over 200 companies will display their products and services in the first ever 3 story expo in Africa!
“For 2015, we’re creating five unique experiences to culminate into Africa’s biggest gathering of qualified buyers and sellers for the entire cement, concrete and construction industry value chain which includes African Construction Expo, Totally Concrete Expo, Coatings for Africa, Housing for Africa and African Roads Evolution, together all 5 conferences and expos will tell the story of shaping the future of Africa’s cement, concrete and construction industries value chain.” Says Soren du Preez, 2015 Programme Director.
Over 170 speakers will present contents in a variety of formats and cover topics as diverse as 3D printing, mega-project development, self-healing concrete, pavement design, enterprise development and investment in infrastructure.
“Our stimulating conference programme pushes innovation in format delivery! We have reliably built an interactive, participant-led experience leveraging expertise and experience to create a conference that you want to be at and actively participate in!” says Du Preez.
Registration and additional information can be found at www.totallyconcrete.co.za
Resource: African Environment