The existing taxi rank on the corner of Katherine Street and Albertyn Road has been transformed into a P-grade office development by Paragon Architects. The Alchemy Properties project, known as 52 Katherine Street, completes the so-called Sasol precinct with a strong street-facing presence.

The design brief was to maximise the permissible floor area ratio, coverage and height as far as possible on what was a complicated site. Standing at a total of four storeys above ground, the building consists of 3.5 basement parking levels. Paragon Architects was responsible for completing Stages 1 through 6 of the works, explains Associate Warren Wesson.

Following bulk earthworks, which took about three months to complete, the main contact commenced in October 2019. The project was scheduled to be completed in December 2020, but was halted due to the Covid-19 lockdown in March.

Once the project was allowed to restart safely, it took a while for the contractor to rebuild lost momentum. Challenges included getting materials to site in time. In addition, the contractor also had to manage additional Covid-19 safety measures. Combined with a very wet summer, the final completion date was eventually moved to April 2021.

The white marble looking walls and strong undulating geometric design of 52 Katherine Street contrasts strongly against the dark organic slate tiled basement façade design of the Sasol head office, giving it its own identity and presence outside of the Sasol precinct.

The façade consists of strong horizontal and vertical elements made up of full-vision dark low-emissivity windows and solid white cladded ceramic tiled walls. The façade is articulated to allow light and views to filter into every office module. The undulating nature of the design creates balconies towards the north and east façade, giving spectacular views over Sandton.

The undulating geometry of the build creates private courtyards in unexpected areas. These courtyards materials include water features, recessed seating and soft surrounding landscaping, which adds to a cool, quiet and shaded atmosphere outside of a busy, loud and hot urban environment.

The building design maximises the coverage of the entire site. Its close proximity to the Sasol head office presented design challenges relating to fire design and compliance. The whole of the south and long west building façade faces onto the Sasol basement façade. Special fireproof Pyron glass had to be introduced for office planning along that façade to receive natural light.

While 52 Katherine Street may look like a simple building, it is in fact very complicated in its interface detailing with regard to the use of glass, aluminium, steel, brickwork and ceramic tiling. “It shows that Paragon Architects can deliver high-quality, cost-effective buildings without the use of the more commonly used and costly unitised aluminium system seen mostly all over Sandton today,” concludes Wesson.