Construction World December 2016

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Building Contractors

As the only surviving example of a Victorian Theatre in Africa, leading specialists in the construction, renovation and recycling of buildings, GVK-Siya Zama was enlisted to ensure that it would be preserved for future generations to enjoy. The topography presented the contactor with tight spaces and tricky heights: approximately 10 m x 10 m, on a 12 m slope of more than 45 degrees. Getting big machines into that space for the excavations was a challenge and the stability of the embankment was always a concern. The contractor excavated from the top down first and continuously made sure that the embankment’s angle of repose was within reliable limits to ensure that there was no slope failure. Options were explored to deal with these challenges. External consultants were called in to conduct thorough geotechnical explorations. Borehole extractions measured not only the water table levels but also the condition of the rock. The contractor decided to dig an additional 1,75 m – more than double foundation depth – and to then build back up again with imported layer works, using soil raft foundation, so that the floor levels of the new and existing building could meet. The foundations were also reinforced to allow for any possible further settlement. Once construction of the new, extended facilities were finished, the project moved inside. • New staircases and lifts were constructed within the shell of the existing building • The original staircases had to be cut out and the existing roofs supported while that support structure was gone As the Opera House is a heritage site, strict regulations were applied to the design and construction work, and the architect received official sign-off before work began. The oldest theatre on the African continent and in the southern hemisphere, the PE Opera House, has recently undergone intricate renovations and expansions. The building was transformed from a heritage site into a first class facility. PORT ELIZABETH OPERA HOUSE

That said, especially on such an old building, once the contractor starts opening up, there are all kinds of surprises and the team discovered that the drawings simply did not match what they found inside. Despite having designs to start with, many aspects had to be redesigned based on site conditions – and as everyone was working in a tight time frame, there were times when pressure started running high. As there was insufficient leg-room for theatregoers in the suspended Gallery, it was decided to increase the size of each step but reduce the number of rows. There were no existing plans of the structure, so new plans had to be drawn up. The size of this upstairs theatre area needed to be increased – however, the rock face is so close to the building that there was simply no room for traditional extension supports. Instead, innovative and modern-looking suspended clip-on boxes were designed to provide additional room. The heavy steel support columns, though, were found to be in the way of the new fire escape, so they had to be shifted around until they were no longer an obstruction. Now in place, they offer a chunky, industrial aesthetic appeal that is in pleasing contrast to the ornate Victorian character of the original building. It is difficult to get a heritage building to within the Green Star rating requirements, because the origin of material and methods of construction are not clear. However, we are always cognisant of environmental best practice and strived to incorporate the Green Star guidelines in terms of our applications. On the Opera House, the contractor used material such a concrete cement containing extenders like fly ash, to reduce the carbon footprint. Approximately 30% of the work was allocated to local emerging contractors, particularly start-up construction labour contractors.

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Project information • Company entering: GVK-Siya Zama Construction • Client: Port Elizabth Opera House • Start date: 24 March 2014 • End date: 20 November 2015 • Main contractor: GVK-Siya Zama Construction • Architect: The Matrix • Principal agent: The Matrix • Quantity surveyor: Markus Burri QS • Consulting engineer: AfriCoast Consulting Engineers • Project value: R24 113 559

Construction WORLD

DECEMBER • 2016