One of the most spoken about new buildings to open its doors in Cape Town recently, has undoubtedly been the new Zeitz Museum for Contemporary Art Africa located in the V&A Waterfront. Originally an old grain silo complex that consisted of 42 33-metre-high concrete tubes, each with a diameter of 5.5 metres.
The mammoth task of redesigning these silos into a functional exhibition space of the highest possible quality, yet being strongly inspired by its own historic character, was given to internationally acclaimed designer Thomas Heatherwick and his innovative team of architects. Their brief was to create a space that would not only pay tribute to its original industrial design and soul, but would become a major, not-for-profit cultural institution that houses the most significant collection of contemporary art from Africa and its diaspora.
It was clear that this was a project that called for a solution that would be unique to Africa. It was therefore only fitting that a unique construction solution developed and used in South Africa – by making use of recycled polystyrene, was to be used for this project.
Greenlite Concrete products were specified by the architects owing to the fact that the structural engineers were concerned about excessive loading to the existing structure.
“The original concrete frame of the old silos building was built in 1924, making the building 94-years-old. The developers therefore needed a screed solution that would not put unnecessary load on the structure, yet would not compromise on quality, strength and durability,” Greenlite Concrete’s Technical Director, Hilton Cowie says.
Concrete blocks manufactured with Greenlite Concrete weigh a quarter of typical concrete. They are also produced in sizes that are easy to handle for quick construction. According to Cowie, more than 2 000 square meters of lightweight screeds were installed – equating to around 200 cubes of Greenlight lightweight concrete being used at the Zeitz Museum Hotel. The total weight of lightweight screeds once installed was around 100 tons, compared to the 400 tons that conventional screed would have weighed.
“We recycle post-consumer polystyrene back into beads through our recycling plants. This material is then used as aggregate mixed with cement and additives to form insulated, soundproof, fireproof, water-resistant lightweight concrete blocks and screeds,” Cowie explains, adding that they successfully recycled and diverted more than six tons of polystyrene from landfill with the Zeitz project. “Our screeds were not only specified for their lightweight aspect, but also for their outstanding acoustic performance which was an important factor for sound proofing the hotel floors.”
With climate change looming and the rising cost of energy, using recycled polystyrene in building and construction applications is becoming an increasingly popular solution for architects and material specifiers. Last year alone, more than 2 036 tons of polystyrene were recycled countrywide for this use in a wide variety of different types and sizes of buildings – ranging from schools, shopping malls, state-of-the-art museums and designer homes, to low cost housing solutions, schools and community clinics.
This material is lightweight and widely used by fast food restaurants and canteens, or as packaging material for meat, fruit and household appliances. “We are urging South Africans to realise the tremendous value of this lightweight material that is not only able to reduce the structural concrete and steel requirements, but offers excellent insulation and ensures significant energy savings,” concludes Adri Spangenberg, Director of the Polystyrene Association of South Africa. “Please recycle your polystyrene!”