Table Bay Mall

July 28, 2022
Roof Structure

A SAFAL STEEL PROJECT SHOWCASE

The R 290-m (so-valued in 2017) Table Bay Mall is an outstanding example of the use of Zincal® AZ200, specified to meet the environmental challenges posed by an aggressive coastal climate. The mall is situated 2 km from the rolling surf of Blouberg Beach, Cape Town and the West Coast is notorious for both wind and sea mist during certain times of the year. In addition, the roofing profile specified, Klip-tite 700 by GRS, dealt with the wind performance criteria in the most economical way at the time.

This roofing was fixed to purlins by means of a KL 700 clip with Class 4 screws, says the roll-former, GRS Roofing.

Architect and director of Vivid Architects of Cape Town, Nic Cloete, says that the mall uses a traditional structural steel truss roof system and that these are supported by the conventional steel/concrete columns. Tilt-up construction methods were deployed on the external walls and coated steel cladding utilised in strategic places to provide a pleasing exterior facade.

“Considering the location of the mall in close proximity to the coast, as well as the mall name, the overall design aesthetic has been inspired and influenced by a contemporary nautical theme. Vivid Architects took inspiration from modern super yachts, incorporating curved flowing lines and using contemporary materials such as glass, stainless steel, aluminium paneling and natural timber. The aesthetic is continued internally with extensive timber paneling, providing a warm texture throughout the mail experience. The mall entrances are emphasised with double-height flushed glazed curtain wall glass, contrasted against polished concrete entrance portals and columns. The extensive glazing provides natural light into the lead-in malls. The inclusion of natural light is an essential element of the mall design and is provided by a continuous central skylight throughout the mall.”

We noted that insulation under the roof is provided by foil laminated insulation batts. In addition, Zincal® has legendary solar heat reflectance of 63% and handles a much higher surface temperature than the popular galvanized steel that is ubiquitous in SA and is a great choice in terms of inbound infrared radiation..

Having developed a number of shopping centres prior to Table Bay Mall, the developer, Zenprop and their professional team were able to utilize some tried and tested building techniques. These include the extensive use of tilt-up concrete panel construction for nearly ¾ of the overall building façade. This has massive implications on reducing the external façade construction time as well as providing a well-finished final product. It does however require extensive pre-planning and resolution of services and structure in order for its use to be successful. In addition, Vivid Architects had to understand the limitations and benefits of the material in order to maximise its use in creating good aesthetic design solutions.

“Rigorous building economics and value engineering continued throughout the design and construction process, resulting in a project that is incredibly efficient from a GLA/GBA perspective, with a construction cost per sqm well below the industry average. This has resulted in a development being completed within budget but completed to a very high standard, with a look and feel that is far superior to the final costs. This is a key element of our approach to create beautiful buildings that are well crafted and cost-conscious”, Cloete concludes.

We say: “Architects and builders are looking for ways to bring individuality, style and character to their projects.

“Steel’s most valuable property is that it can be recycled many times without loss to its inherent qualities. In fact, it is the most innovative, recyclable and sustainable material of the 21st century. Indeed, one of the environmental highlights of the Table Bay Mall project has been identified as the fact that all reinforcement steel utilised on the project has been manufactured and procured from recycled steel in addition to the already high recycled content of our product” – Safal Steel.

Products used & contractors

life-expectancy-of-az-tech-graph

SAFAL AZ200 G550 Zincal®. Specified due to meeting performance criteria to proximity to sea and requirement for 20 year guarantee. Vertical cladding (as per the AZ150 roof sheeting) was used where roof returned to tilt-up façade  or other outer wall surface.

 

Product – Safal Steel: Zincal®AZ200 TCT: 0.53mm

  • Roof: 79 000m2 53mm AZ 200 Klip-tite 700 Zincal®
  • Cladding: 5 000m2 53mm  AZ200 Klip-tite 700 Zincal®

Roll former: Global Roofing Solutions, Cape Town  (Craig Uys)

Roofing/cladding contractor: Chartwell Roofing (Toyer Royepen)

Roofing & Cladding material Supplier: Safal Steel

building roof development

Professional team

Client/developer: Zenprop

Architect: Vivid Architects

Main contractor: Group 5

Project managers: PCPM and WT Mcclatchey

Engineers: Structural, civils, plumbing/drainage & fire: Aurecon

Mechanical engineer: Graeme Page Consulting Engineer

Electrical engineer: Quad Africa Consulting

QS: MLS

Photography by: Peter Hassal, Gareth Griffiths and Vivid Architects

view of building roofing from the inside

About Zincal®

Safal Steel is a licenced user of the highly respected 55% Aluminium, 43.5% Zinc and 1.5% Silicon coated steel technology from BIEC International Inc. The company is the first and only

licensed producer of this patented coating alloy in Southern Africa, which is used to manufacture the highest quality metallic and pre-painted coated steel used in roofing, cladding, and many other structural applications.

This coating on Zincal® protects the steel substrate in two ways: The aluminium part of the coating provides a tough physical barrier, while the zinc component  provides sacrificial protection, also protecting the steel at the cut edges. The superior corrosive property increases the life of the steel core up to four times longer than that of conventional galvanized steel. An additional huge advantage of Zincal® or Colorplus® is its lightweight nature when compared with typical galvanised steel. This lends itself to modern sustainable construction methods, promoting dematerialisation, lower transport costs, longer life in service and reducing the footprint of the building on the earth.

zinc roof sheets

About our warranty

Safal Steel warrants its Zincal® and Colorplus® (colour coated steel) to have a service life (prior to perforation by weathering in the natural elements) from date of installation. Warranty periods are determined by Safal Steel and may vary according to project design and location. A Provisional Warranty may be applied for at project design stage; this warranty serves as a guideline as to the final warranty Safal Steel may issue on project completion. A Final Warranty application form may be submitted to Safal Steel by the roll former on project completion, requesting Safal Steel to issue a warranty for the specific material used on a specific project.

Look for the trademark. All Safal Steel prime material is branded on the backing coat – insist on Safal Steel material.

For any technical queries please contact Safal Steel and ask for the representative in your area.