The art of inefficient building in South Africa is by no means restricted to low- cost housing. Like clothes and cars, the design of modern South African buildings is only partly to provide utility – it’s also important to signal the status and fine taste of their owners. In doing so they have lost a lot in function. But while economy is often touted as a good reason to buy a particular car, buildings are never advertised as providing “350 un- airconditioned days a year”. Architects have come to specialise in the construction of anachronistic styles – neo-Georgian, Tuscan or Aegean – but pay attention only to looks, ignoring possible environmental efficiencies or deficiencies. Nicole Tsandelis, a practising architect who has never had an opportunity to construct an energy-efficient building, blames the financial imperatives of developers and landlords as much as the tastes of consumers. For builders the economies of building dictate that they can charge most for roofs and floors, she says. Walls cost comparatively little. When one asks for temperature-moderating devices such as verandahs or eaves, they add dramatically to cost, but do not add to the floor area of the dwelling, which is currently the benchmark for measuring the value of a building.
People ignore the “physics of building”, she argues, in favour of the status or style denoted by particular building fashion.
So how does one set about creating a self- regulating highveld home? In winter the aim is to capture sunlight during the day. Sunlight that is allowed to fall on to black slate flooring is absorbed, then radiated at night. This process is almost absent when the floor is carpeted. Thicker walls which increase “thermal mass” resist heat radiation during the day and radiate heat at night. A courtyard with a fountain can provide natural air conditioning for surrounding rooms. An unpowered whirlybird (chimney with a wind-driven extractor fan) installed on the roof to pull out hot air can dramatically reduce the inside temperature. Overhangs – deep eaves, verandahs, loggias – can be designed to admit the sun in winter but keep it out in summer when it rides higher in the sky. But developers don’t like overhangs, deep eaves or covered verandas – witness the many townhouse complexes in which dwellings are left completely naked of any shade- creating devices. “If it’s not rentable, they don’t want it,” says the frustrated Tsandelis. Irurah says new technology is now also making self-powering buildings far more practical. R5 000 buys a solar power-cell system that will support an entire household. Solar water heating is another way of reducing energy inputs and is extremely popular in Israel and Australia, though neglected in South Africa. The tendency to appropriate the wrong trends in world architecture is by no means limited to private dwellings. Tsandelis points out that the ubiquitous glass-clad skyscraper was designed by architectural legend Mies van der Rohe for the German climate, where there is low solar radiation and lots of rain to keep windows clean.
When that design paradigm was transplanted to South Africa, in the form of the Johannesburg Stock Exchange building in Diagonal Street, the reflected solar radiation knocked up the air-conditioning bills of neighbouring buildings by up to 40%. The top three floors of the JSE building are dedicated to the air- conditioning plant and the windows need frequent cleaning. Not that South Africa is alone in being swayed by the wrong design traditions. Tsandelis has worked in the Middle East, where traditionally people built with stone or mudbrick to create perfectly cool dwellings ventilated by specially constructed chimneys. But the glass skyscrapers of the oil economy have supplanted such elegance. “People have to invent ways to spend money and seven floors of air-conditioning seems like a cool way to do that” she says.