The BMW headquarters in Midrand were given a modern look with the installation of a Rheinzink prePATINA blue-grey roof and facade.

The transformation of the South African property industry to ensure that buildings are designed, built and operated in an environmentally sustainable way continues apace. Apart from building green, property owners are taking the opportunity when refurbishing existing buildings to use resources efficiently and address climate change, while creating healthier and more productive environments for people and communities.

The refurbishment of BMW South Africa’s headquarters in Midrand is one such project.

The building was originally designed by Hans Hallen in 1984/85 and has become an architectural icon adjacent to the Pretoria-Johannesburg highway. The recent modernisation, devised by Boogertman + Partners Architects, reflects BMW’s corporate identity while embracing South Africa’s energy efficiency and sustainability principles.

In equipping the building to face the future on an equal footing with contemporary developments, the lighting and ventilation solutions underwent a complete reinvention. Another significant area of renovation involved roofing and the facade.

The circular roof and facade
The old slate was removed for reuse in feature walls in landscaping and replaced by the contemporary aesthetic of zinc sheeting. The chosen titanium-zinc alloy, Rheinzink prePATINA blue-grey, was installed on a 2 600m² area by Rohde Roofing CC, using a double-standing seam system – a complicated installation since all the roof sheets had to be tapered and crafted on the circular roof.  

Rheinzink prePATINA blue-grey was also chosen for a 500m² facade area and installed through use of a flat-lock tile system with an angled standing seam.

Rohde Roofing CC, which has been installing Rheinzink since 2005, is led by Fred Rohde, a master roofer who learned the trade of hard metal crafting in Germany.

Titanium-zinc building material
“The choice of Rheinzink for the BMW refurbishment is yet another example of how South African architects are increasingly turning to the titanium-zinc alloy, as a long-lasting and maintenance-free building material, to enhance design options and to meet the challenges of energy efficiency and sustainability,” says Stephen Wilkinson, Rheinzink’s sub-Saharan Africa regional director.

Energy use and sustainability are essential design considerations, both during the construction process and for lifecycle building costing, and with Rheinzink’s low primary energy demand and 100% recyclability, all criteria are successfully fulfilled. Consequently Rheinzink carries top German and European quality certificates and the environment certificate IBU based on lifecycle analysis (LCA).

Wilkinson also emphasises that durability is a vital consideration in the choice of roofing and cladding material, and together with the aesthetical quality of the pre-weathered sheet finish, Rheinzink provides a complete technical and sculptural solution.

As an alloy, Rheinzink consists of 99,995% high-purity zinc and precisely defined amounts of titanium and copper, and is not merely coated with zinc, as with galvanised steel. This allows for maximum structural integrity. The company asserts that with proper design, fabrication and installation, a realistic roof life expectancy of 100 to 120 years can be expected and 150 plus years for wall cladding.

Rheinzink
Tel: 021 671 2600
Email: info@rheinzink.co.za
Website: www.rheinzink.co.za

Award-winning revamp
The building was honoured with:
•    The South African Property Owners Association 2015 award for refurbishment.
•    A five-star Green Star As Built rating from the Green Building Council of South Africa.
•    A special award in the GIFAwards 2015, presented every two years by the Gauteng Institute for Architects to recognise and celebrate outstanding achievements and excellence in architecture and the built environment.

These awards acknowledged efforts to enhance the building’s natural light, energy efficiency and thermal comfort, as well as achieve a considered, productive working environment.