Architect and Builder August/September 2019 | Page 55

resistance to seismic events are well document, hence it needed no additional motivation as the building material of choice. In addition to the above, developments in concrete mix designs over the last few years have increased the environmental consideration of concrete use, specifically relating to incorporating slag in the concrete mix. The concrete contained a high slag content, which is a by-product of steel production, is used to ensure the durability of the concrete and limit early thermal shrinkage/cracking of the concrete. Special care was taken with both the mix design and the construction procedure. Pour breaks and construction joints were carefully considered to mitigate the impact of shrinkage and the erection and installation sequence of the construction. Casting of floor slabs was mostly scheduled to occur in cooler temperatures during late afternoons and early evenings to assist in reducing the effect of heat and cold on materials (thermal effects). Given that the construction took place as the City of Cape Town was experiencing a drought, snagging was offset using a combination of curing compounds, wet sand and hemp sheets for vertical members. The building is a calculated play on concept, massing and forms whilst addressing intense requirements from a space planning and work environment point of view. The result is a building which has successfully created an inspirational environment where the organisation has flourished and settled for years to come. 1ST FLOOR 3RD FLOOR Water & Sanitation 6TH FLOOR 55