Designing high-rise buildings to include mixed-income housing : A Cape Town case study

by Jochen Schmidt von Wühlisch

Architectural challenges of urbanization in South Africa

Many people are unaware of the significant responsibility architects have towards society. As designers of the built environment we are the shapers of the vast urban spaces which, by 2050 over 70% of earth’s population will inhabit. This projected growth not only intensifies the challenge the profession faces, but also puts emphasis on one key responsibility of our work: The task of figuring out how to create an environment that helps create equal opportunity, egality and general wellbeing for all its inhabitants.

This challenge is, as most of us are aware, one of the most important aspects we have to confront in South Africa. Apartheid Spatial Planning has left a legacy that shaped and is still shaping our cities in a way that only perpetuates the inequalities plaguing our society.

From this, a chorus of conversations have sprung in all directions about how we are to undo this legacy, and how we should shape the urban environment for the future growth of our cities and the people that live within them.

Purpose of the thesis

My thesis for the masters in architecture was aimed at synthesising a design method that allows professionals to utilize architecture as a social tool to create public spaces that facilitate the evolution of collective identities of South Africans. Spaces that lend themselves to bringing people together during their everyday lives, spaces for exchange, spaces for engagement. One aspect of the exploration in the thesis dealt with residential typologies: A study of how we can use residential developments in our cities to bring people back together into one space.

The main argument of the work acknowledges that the current response to city sprawl has been a reactionary trend towards densification of our city centers. And while in and of itself this does make sense, one must ask who the targets for densification are? Densification logically equals taller buildings, thus more expensive real estate, and therefore more and more people are either evicted from their current areas of community through gentrification, or excluded from ever being able to be reintegrated into the fabric of the city.

My thesis chose the Cape Town Station as a testing ground for all the theories that grew from the exploration it undertook. As part of the work, I studied the Cape Town Station in terms of its relationship with its surrounding context, in terms of density and height, and concluded that it was a strong indicator that the site needed to be utilized much more efficiently, for the sake of dense and economic use of already limited space in the city.

Cape Town station within larger context of the Cape Town CBD

Diagram of land ownership in the CBD. This image illustrates the disproportionate amount of area taken up by the Cape Town Station, compared to the surrounding fabric of the city.

Diagram of public space in the CBD illustrating the disruption of public space by the infrastructure of the Railway Station, if not used in more ways than currently.

Potential of the Cape Town CBD and Cape Town Station

In terms of high-rise developments though, the city centre is saturated with commercial office space. Over the last few years there has been a steady amount of vacant office space in the Cape Town City Center (Colliers International Quarterly Market Analysis), indicating that this market has been saturated. However, the City of Cape Town has marked an area along major routes and centers as Urban Development Zones (UDZ). These zones are subject to special policies that grant developers tax deductions for different types of development. Low-cost high-density housing is categorized with the highest rate of 25% tax deductions over 11 years.

Model of the Cape Town Station context

The Cape Town Station falls within the UDZ. And due to the sheer amount of space it inhabits in the Cape Town CBD, an alteration and/or further utilisation of this space should be explored in order to give it back to the city and its people. As part of a larger master plan in the thesis I proposed a mixed income high-rise development as a pilot project to show how residential architecture could be integrated into an area usually dedicated to only the infrastructure of transport.

As it currently stands, the daily life of the station precinct is limited to hours of operation and is quiet and under-utilized over weekends. A residential complex within the Cape Town Station precinct would extend the lively hours of the day to 24 hours, as well as 7 days a week. This makes high-rise or high-density residential development in this area more feasible. The UDZ classification would make the proposal of mixed-income high-rise developments part of the greater solution our city requires.

Precedents in big cities around the world illustrate the success of blended-complex models, comprised of subsidized social housing units and market rate private residential housing. Of course here in South Africa, for mixed income housing to be scalable, we will require a shift in mindset and more changes in policy on a municipal level. In the meantime, however, the proposal for a high-rise residential building at the Cape Town Station can be viewed as a pilot project for a new concept of blended housing in the inner city.

The residential tower

The concept for this residential tower is relatively simple. It is derived from taking a row of walk-up three storey buildings in a linear arrangement and re-arranging them in a courtyard. This arrangement could then be transformed into a cell which will be stacked on top of one another, resulting in a denser, vertical version of what usually is a fairly standard layout for general residential developments.

Diagram illustrating the concept of the three storey cell.

The idea of splitting the overall high-rise building into smaller cells is aimed at bringing down the scale of the communities within the building and thus supporting a smaller communal engagement amongst tenants. Each cell would follow the idea of blending market rate apartments with affordable units, as well as subsidized social housing. This would avoid the temptation to locate the richer tenants at the top of the building, and affordable/social housing tenants at the bottom; Which in itself would contradict the intent of integrating groups of society within the building. Each cell within the building also has its own courtyard which is shared by the residents of the three storey cell. This shared space encourages community, allows for a sense of unity, and provides the space where people can interact with one-another outside of their homes.

The integration of social housing 

While mainly the current conversation around residential developments in Cape Town’s CBD leans towards more affordable housing; a fairly more important question which should also be dealt with is how one integrates social housing into a mixed-income development. The national social housing project is run by the Social Housing Regulatory Authority (SHRA). This government body, headed by the Minister of Human Settlement, facilitates the construction/creation of social housing, and also manages the implementation and regulation. The proposal for a mixed-income, blended high-rise residential building in the CBD would be achieved by the collaboration between SHRA and the private sector developer. This would increase the social impact of such a development by not only having a mixture of market rate apartments and affordable units, but actually also include subsidised social housing units. If a specific amount of units in a building are able to be built, so that they can be offered at a cheaper rate through the tax incentives offered to developments in the UDZ (and simple cost savings on finishing etc, instead of square meterage), these units could match the criteria to be incorporated into SHRA’s Social Housing Investment Programme.

Social housing is typically aimed at the upper end of the lowest income groups (R1500 – R7500pm) and also relies on government funding. This can have the effect that social housing developments are usually built cheaply and without any emphasis on the architectural quality and character/aesthetic of the buildings. The concept of mixed-income high-rise residential developments has the potential to break this mold. Moreover, the possibility of integrating private sector investment, and/or the provision of large tax incentives to developers applying the mixed-income housing concept to their developments, would create a larger budget and allow these buildings to be designed with more care for aesthetic. So apart from finally creating opportunities for people from the whole spectrum of income brackets to be accommodated in previously exclusive areas of the city, it also gives the people living in these ‘blended’ buildings, especially the people who inhabit the social housing units, more integrity, a sense of value and a stronger identity.

Strand Street view of mixed-income residential tower, within larger master plan of proposed Cape Town Station re-design

Station Square view of mixed-income residential tower, within larger master plan of proposed Cape Town Station re-design

Jochen Schmidt von Wühlisch was born and raised in Namibia, and moved to South Africa to pursue an architecture education in 2006. After finishing his undergrad at the CPUT he spent five years gathering experience in the profession, and finally completed his architecture studies with the Masters in Architecture at the University of Cape Town in 2016. Jochen is passionate about pushing boundaries when it comes to architecture as an art, and architecture as a tool for social evolution. He strives to grow his career in order to successfully make a meaningful impact through his work. 

All content and views expressed in this article remains the property of the author(s) and does not constitute an endorsement by Future Cape Town.

Read other articles on housing in our 80:20 Series:

Image Credits

  • All images supplied and owned by Jochen Schmidt von Wühlisch


  1. Colliers International
  2. SARS
  3. Cape Town Partnership – How to: Make the UDZ work for you
  4. The New York Times
  5. Social Housing Regulatory Authority (SHRA) – About
  6. Social Social Housing Regulatory Authority (SHRA) – Capital Invetsment
  7. Regulatory Authority (SHRA) – Investment Programme
  8. Cape Town Partnership – Affordable housing in the central city: frequently asked questions

This article was based on the thesis “(Re)Programming Typologies of Public Infrastructure to serve as a Tool for Cultural Evolution: A Re-imagination of the Cape Town Station” by Jochen Schmidt von Wühlisch; University of Cape Town; 2016.