With 3 000m² of glass on the outer facade alone, the Cape Town Convention Tower is itself an exhibition of the use of glass in commercial building. Not only does the amount of glass incorporated make the tower aesthetically appealing, but it makes it extremely energy efficient as well. Taking 14 months to complete, the project, by architects Dennis Fabian and Berman, needed to provide more than just office space.

Before April of 2008, the five star Western Grand Arabella Quays hotel was the prized ‘glass jewel’ of the Cape Town skyline. Now, the Cape Town Convention Tower offers unparalleled competition, with its beautiful exterior glass facade and high-rising curtain wall boasting spectacular views. It is little wonder, then, that it is the most coveted office complex in the region. Diagonally east of the Convention Centre, in the vicinity of both the V&A Waterfront and surrounding hotels, the Convention Tower is the perfect location for exhibitioners and businesses alike.

Convenco gives the go ahead
Madison Property Fund Managers, on behalf of the Redefine Property Fund, won a tender to lease the land and awarded the project to Dennis Fabian of Dennis Fabian and Berman Architects, for his perceptive design. A design that not only met all of the stipulated requirements, but also allocated the ground floor to the Cape Town Convention Centre (CTICC), providing them with much needed additional exhibition space.

Apportioning the 1 300m² ground floor with its clear height of 9m as a much needed extension of the very successful CTICC, architect Dennis Fabian briefed engineer Brian Richardson to design an 85m long by 6m deep supporting beam that would allow them to build five levels of parking, 2 mezzanine floors, seven levels of office space and a penthouse with terrace above the Convention Centre area. With limited tenants the developers agreed to proceed having been granted the air rights to the land in exchange for constructing the extension to the CTICC.

The gorgeous views, high-tech modern feel and prime location of the building saw every square metre of office space let out before the building was completed, all of which project architects Francois Engelbrecht and Glen Louden capitalised on with an outer facade that consists of about 85% of glass.

Design concept
The design of the building, according to Louden, was ‘simply about mitigating the proportions of the east facade that accentuated the horizontal length of the building with the vertical cores of the north and south elevations, which, seemingly, reduced the width of the north and south facades’. In other words, the focus was on accentuating the horizontal length of the building without reducing its width. The lower floors also needed to incorporate the design language of the existing CTICC, so sandstone clad columns were used, bringing the Convention Centre motif into the new convention space.

Engelbrecht adds that the restricted space forced them to build higher, a fortunate necessity which gives the building its unique appeal. The extensive use of glass on the exterior intended to capture the views of Table Mountain that building higher had afforded them. Not only aesthetic, however, the glass is also employed to help reduce the building’s energy consumption, even though the legislation governing the use of glass for this purpose had not been passed when the project began.

The double glazing installed on the curtain wall on the western and northern sides by Mazor Aluminium, maximises the use of natural light, while reducing the load on the air-conditioning. The eastern facade features sun control louvers for the same purpose.

The glass facade
The exterior of the building is comprised of 2 000m² of Solarvue Serene Green and 1 000m² of Insulvue Solarvue Serene Green Low E. The latter ensuring a green building rating, energy efficiency, solar control and aesthetics. The Solarvue Serene Green reduces heat and eliminates UV rays while still letting in a considerable amount of visible natural light. The PVB coating between the two sheets of glass in Solarvue Serene gives the building a unique, distinctive colour at different angles of reflection.

The Insulvue, commonly used in airports and computer rooms for strict atmospheric control, moderates extreme ambient temperatures via a 6mm or 12mm space of dehydrated air between two double glazed sheets that are held apart by a metal spacer.

Although the innovative use of glass is not confined to the exterior of the Convention Towers. The meeting and boardrooms on the eleventh floor, for example, feature GSA’s privacy glass. This premium product consists of liquid crystal plasma that is laminated between two normal sheets and instantaneous privacy is activated by an electrical current. Normally transparent, the glass can be conveniently turned opaque with the flick of a switch.

A beautiful reflection
The three thousand square metres of exterior glass not only maintains the building’s ‘green’ status, but aptly exhibits the views of Table Bay. Even at night, when the natural light is negligible, the LED panels framing the building maintain its visual appeal, justifying Fabian and many others’ declarations that the Cape Town Convention Tower is, indeed, “the most beautiful building in Cape Town”.