Cape Town hotel to feature in London architecture exhibition

Tsogo Sun hotel complex in Cape Town, designed by Dexter Moren Associates

The London: Design Capital exhibition forms a key part of NLA’s expanding International Dialogues programme, a year-round programme of international conferences, visits and debates to share best practice and foster cross-city dialogue. The exhibition features 220 projects in 65 countries around the world to showcase the global reach of London’s built environment profession.

The Tsogo Sun development is one of 21 projects from Africa that are being showcased.

'Quintessential African feel'

South African-born and London-based Dexter Moren, founding director of Dexter Moren Associates and architect for the project, says: “The design of the hotel is a merger of the best in global architectural trends with a quintessential African feel. It was important to us that the design respected Cape Town’s rich heritage.”

“The site is a prime location in the city bowl and posed some interesting heritage design challenges”, he continues. “The top of the hotel has a distinctive profile which works with the taller scale of surrounding buildings on Strand Street. The middle reflects the rhythm and proportions of the typical Bree and Buitengracht Street buildings, while the base has been designed for the pedestrian, with canopies, active frontages and street block diversity.”

DMA were selected as the architects for the hotel by Green Willow Properties, owners of the hotel site, after participating in a design competition in 2014.

Principles of passive design

The firm drew on its experience in hotel design to optimise the efficient and sustainable internal spatial planning of the hotel and used the principles of passive design wherever possible to make the most of the specific conditions of the Cape Town site.

The adopted building massing, notably the lower scale base and centre block vertical tower, is designed to sustain the natural light reaching all streets in the city block development. This approach aims to enhance the existing trees surrounding the site, sustaining the greenery and ecology in the city and providing natural shading in the summer. In addition the design enabled an additional row of trees on Strand Street.

Projecting canopies at street level allow for all-year weather protection for pedestrians and create solar shading to the extensively glazed shopfronts at street level, protecting them from excess solar gain and reducing the demands on artificial cooling. In contrast, at roof level, the swimming pool and associated roof-deck have been located to optimise solar exposure.

Spaces that don’t require artificial cooling, such as the carpark, have been designed to benefit from natural cross-ventilation, achieved by the use of a perforated brick façade. Whilst permitting natural air circulation, the brickwork creates a visual screen to the street which provides an animated facade when backlit at night.

Limiting heat loads

In contrast to the fully glazed facade approach, windows are located within a generally solid façade to optimise focused views while maintaining a passive building envelope. The windows also feature double glazing with SolarVue solar control glazing, limiting heat loads on the building, heat losses in the colder periods of the year and providing an acoustic barrier to traffic and wind noise. The brick work used on the facade and internally also has the dual benefit of having a high thermal mass which works to both absorb and release heat energy keeping the building cool, whilst the tiling, which is part of a 'rain screen' cladding system, acts as a solar shade.

By preserving, renovating and reusing the historic Tothills Building, DMA has ensured it remains a part of the cultural heritage of Cape Town.

Moren adds, “We are proud to be featured in the NLA London Design Capital exhibition to celebrate the capital’s creative minds and breadth of expertise. It showcases a variety of interesting and amazing global projects that are hopefully an inspiration to many in the built environment.”