Recycled PS in screeds & blocks at Zeitz MOCCA museum


PHOTO: The Zeitz MOCCA Museum for Contemporary Art in the V&A Waterfront in Cape Town

ONE of the most spoken about new buildings to open its doors in Cape Town recently, has undoubtedly been the new Zeitz MOCCA Museum for Contemporary Art in the V&A Waterfront. 

Originally an old grain silo complex that consists of forty-two, 33-metre-high concrete tubes – each with a diameter of 5.5 metres - this was once the tallest building on the Cape Town skyline.

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 specified

Greenlite Concrete products were specified by the architects as 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,” said Greenlite Concrete’s Technical Director, Hilton Cowie.

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 000m2 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 explained, adding that they successfully recycled and diverted more than 6 tons of polystyrene from landfill with the Zeitz project. 

“Our screeds where 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,” Cowie added.

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.