The relationship between climate, construction trends and human influence in West African vernacular architecture
In previous articles (AR September 2009 and AR February 2010), I described the vernacular architecture I experienced while driving down the west coast of Africa. The route was dictated mostly by the availability of roads, avoidance of hostile areas and a small architectural detour into Burkina Faso. I discovered that vernacular architecture is not grouped by national boundaries, but rather by climatic region.
Due to high levels of poverty, the vast majority of West Africans live in shelters made of the cheap, natural materials or vegetation found around them. As native vegetation is an expression of climate, grouping architecture by region links it directly to construction techniques. Building solutions and forms have thus evolved from the availability of materials and in response to climate. And while there may be an infinite number of architectural variations between villages, inhabitants are still limited to using what is available locally.
Six major climate regions span Africa’s length. Driving south to the equator, these go from Mediterranean to desert, Sahelian, savannah (also known as a tropical climate with dry season), humid tropical to equatorial climates. As I passed the equator, these reversed until culminating in the equable Mediterranean climate of South Africa. Heading south, it was possible to predict (with relative accuracy) climate and therefore vegetation, allowing me to suppose the types of building materials, techniques and architectural forms that might be particular to certain regions. Crossing the equator, I wanted to prove that I had been right in grouping African vernacular architecture by climate, expecting to see the sorts of buildings I had already experienced in corresponding climates north of the equator.
I crossed the equator deep in Gabon. Movement through the equatorial rainforest is slow and dangerous, restrictive to both life and architecture. The predominant building technique across all regions involves a timber lattice or cage, which is then covered in a mud plaster that expands as it dries, strengthening the structure. Roofs are typically constructed with reeds or grasses and windows left open, exposing the lattice in order to maintain structural integrity. This unusual technique dominates a climatic region covering literally thousands of miles. I first witnessed it in Sierra Leone, again in Liberia, Nigeria, Cameroon, Gabon, the Republic of the Congo and deep in its neighbour, the Democratic Republic of Congo. This begs a difficult question: were these identical construction techniques developed in isolated pockets or dispersed through trade and travel?
The spread of knowledge across northern Africa has traditionally been impelled by a number of factors. Small empires such as the Mali empire cultivated and spread knowledge; Islam grew and developed; and the nomadic tribes of Berbers and Bedouins travelled and traded over huge distances, bringing goods and ideas from elsewhere. But life in equatorial Africa has always been very different. Communities are small and fragmented - there are over 10,000 tribes in what is now Nigeria alone. Given the difficulties of travel, combined with the danger of animals and tropical disease, how were these construction techniques disseminated? My sense is that, though land travel in the region is difficult, people (and their ideas) moved by rivers and the sea.
As with the equatorial regions, there is a strong correlation between building types of the humid tropical and savannah climates on both sides of the equator. In the Congos I witnessed the same grass-roofed, mud-walled huts typical of Ghana, the Ivory Coast, Togo and Benin. In the drier tropical savannah climate of Angola, these mutated into huts with increased air circulation, enclosed by lightweight walls of reed and timber. However, beyond these regions, the similarities in vernacular architecture diminished. I now understand that things are far more complicated in Africa than they first appear to be. Undoubtedly, climate is a major shaping force, but there is also a significant human influence.
It is also important to acknowledge the differences between northern and southern Africa. To get some sense of this, the journey to the equator took four months, passing through 18 African countries. By contrast, the journey from the equator to Cape Town in South Africa took only one month and passed through six countries. This is mainly due to geography, but it is also to do with infrastructure. Better infrastructure promotes trade and, as in other parts of the world, many African communities develop and thrive along major transport routes.
Access to imported materials negates the need for a more improvised, local vernacular. With the exception of the Democratic Republic of Congo, vernacular architecture is less common south of the equator.
Without doubt the most memorable examples of African vernacular were all sited in some of the poorest countries in the world, such as the Democratic Republic of Congo, Liberia and Guinea-Bissau. Conversely, South Africa, Namibia and Angola have a far higher GDP and GDP per capita, so buildings tend to be more ‘evolved’. Angola has oil money and substantial credit from China to rebuild public infrastructure. Namibia exports minerals and diamonds and its economy is closely linked with South Africa. South Africa has an abundance of natural resources and well-developed financial sectors. Even the Republic of the Congo has oil money and new roads, thanks in part to its president Denis Sassou Nguesso who has had a tarmac road built to speed his journey from the capital Brazzaville to his home village of Edou in the north of the country. Another human factor is population size and distribution. Namibia, for instance, has the second lowest population density in the world, after Mongolia. In more densely populated Angola, however, nearly 60 per cent of the population live in urban environments; similarly in South Africa this figure is over 60 per cent. These factors all have a profound effect on vernacular architecture, traditionally found in rural settings.
To a lesser extent, cultural influences produce variations between north and south. It was noticeable that the Sahel climate and desert regions south of the equator (such as the Namib Desert) are devoid of tent structures associated with the Sahara because there are no Bedouin and Berber tribes in this region.
Thriving trade routes did not exist south of the equator and Islam is not prominent, so there are no casbahs or moulded mud mosques.
But while south of the equator might be without the influence of nomadic tribes, there are many other ethnic groups in their place. In the Republic of the Congo I stayed with an ethnic group called the Bakongo or Kongo people, whose architecture was very different to anything I had seen before. Structures were rectangular, with pitched roofs made from a structural timber frame completed with woven walls and roofs. In some instances they also had slot windows and sliding doors. Construction was undertaken in stages, built in equal modules of varying arrangements; some in a U-shape around a small garden, others in a line. Those dwellings arranged in a line had pitched roofs in different directions that produced a very distinctive assemblage. Inside the houses, beds and other furniture were constructed using the same technique. Doors could be locked, windows closed.
In another Bakongo village I witnessed an individual (the local witch doctor) who had built himself the only two-storey house in a 100-mile radius, to literally ‘elevate’ his status. Mr Delaspe was exceptionally proud of his mixed-use building with its ground-floor surgery and living accommodation above. The entire building was dependant on a tree, the cornerstone of its structural integrity. Every timber member had been tied to it where possible, but despite this, the house still tilted alarmingly. Downstairs, the surgery was subdivided into a treatment room and another full of bottles and jars. These oddly shaped containers were full of liquids and animal parts characteristic of the traditional Kongo religion. Upstairs was accessed via
a ladder (missing several steps) leading to bedrooms and balconies, one covered and one exposed. It was one of the most incredible handmade structures I have ever seen.
This was not an isolated case of inventiveness. West Africans are masters of creating solutions out of whatever is at hand. On a populated coastal region in Angola I spent some time at a local bar created entirely from rubbish. In all my West African travels, these last two buildings made the most powerful impression. Idiosyncratic in nature, both are a response to and an expression of the surrounding community. As with most vernacular dwellings they are constructed and maintained not by the individual but by the community, whose lives are affected by the presence of built form. So ultimately, what I thought would be a 30,000km architectural journey, turned out to be more about the local people and my perceptions of them.