The AR travels through three climatic zones on the West coast of Africa to discover the region’s myriad strands of vernacular architecture
This is an architectural journey through the west coast of Africa. Why the west? Because the east coast of Africa is a path well trodden and well documented - the champagne tour of Africa. But as east Africa’s bad older brother, west Africa has a far darker reputation. Very little is written about it, especially its architecture. For so long, much of west Africa has been inaccessible through war and coups d’état.
My trajectory took me through every country with a coastline and en route I visited and stayed in many different kinds of vernacular dwellings.
In doing so, I experienced some of the most inaccessible, beautiful or unusual sights on the planet: kasbahs in Morocco, minefield borders in Western Sahara, the Sahara Desert in Mauritania, wrestling in Senegal, slave stations in Guinea-Bissau, mines in Guinea, diamond mines in Sierra Leone, rainforests in Liberia, mass deforestation in the Ivory Coast, savannahs in Burkina Faso, stilt villages in Ghana, voodoo in Togo and Benin, surfing hippos in Gabon, the Skeleton Coast of Namibia and South Africa’s Table Mountain.
This survey looks at vernacular building in three different climate zones north of the equator. By its very nature, vernacular architecture inhibits classification, as it depends on tradition, social norms, domestic priorities, climate and the availability of skills and materials. These factors vary from country to country, region to region, village to village and even family to family
To categorise by country would disregard the context of African history, in that most African countries and borders have been artificially created by European colonial powers over the last hundred years or so. Going further back in history, it is possible to trace the influence of Africa’s indigenous empires on the vernacular, but again this gives an incomplete picture.
Most villages I visited were organised by families or clans who use architectural means to identify themselves. Walls are painted with family motifs, ventilation holes form characteristic patterns, and even the men bear scars on their temples to indicate clan membership. The number of African clans is enormous. In Nigeria alone there are 36 states, with 250 ethnic groups and 521 languages, giving some indication of Africa’s powerful and pervasive tribal history. Identifying cultural influences is clearly not a complete system for analysing African architecture.
Driving through this vast continent, there is one glaringly obvious common denominator: poverty. As a result, the vast majority of Africans live in shelters built from cheap, natural materials or the vegetation found around them.
As local vegetation is linked to climate, grouping architecture by climatic region helps to explain construction techniques. While there may be an infinite number of architectural variations between villages, inhabitants are still limited to the availability of materials in their certain climatic zone. So while scale, function and details can vary, construction techniques are broadly similar due to the inherent properties of these materials.
Desert climates extend from northern Africa to below the Tropic of Cancer. The Sahara, a vast, barren and desolate swathe of land, dominates north Africa. Natural shelter is hard to come by and protecting inhabitants from the sun is essential. On the edges of the rolling sand dunes of the Sahara, vegetation may be scarce but rocks are plentiful. In Morocco, houses are made of local rocks, built using dry-stone walling, a technique similar to that found in rural parts of the UK.
Roofs are constructed by stretching a large piece of fabric across the structure and anchoring it in place with rocks along the edges. To repel sandstorms and heat, windows are typically small and high, and sometimes non-existent. In common with other desert structures dwellings are dark and cool inside.
Along the coast of Western Sahara and Mauritania, the desert meets the sea in spectacular fashion. Inhabitants are either fishermen or soldiers (patrolling the coast for illegal immigrants coming ashore), who construct huts from driftwood and anything else claimed from the sea. Without natural materials, these coastal structures are an eclectic mix of wood, plastic bottles and other discarded materials washed ashore, all wrapped in fishing nets. Roofs are usually constructed either from fabric or timber planks and are tied down and anchored with large rocks to protect against fierce sea storms.
Across the Sahara, I encountered Berber and Bedouin desert nomads with their famous tents. Strips of cloth are sewn together on ground looms or by hand; originally these were made of goat hair, now brilliant white canvases reflect the desert sun.
Strips are held in tension with anchored ropes, the number of which varies depending on the size. Either a single central pole or a ridge (to prevent the pole piercing the fabric) gives the tent its shape. The loosely woven fabric creates a cool space inside by allowing air to circulate and contracts in the wet to protect its inhabitants from leaks. Bedouin tents in the Atlas Mountains have steeper pitches for snow than the flatter variants in the Mauritanian desert.
The availability and flexibility of mud has made it the most common building material, from the top to the bottom of Africa. Typically used for wall building, its application and properties vary enormously. Chemically there are many types of mud, all with their own qualities, acidities and colours. Dry desert soils of rock and sand are alkaline and especially suitable for building.
The combination of these properties have been utilised over centuries of desert trading, culminating in the mud-built kasbah. While the Bedouin tent is lightweight, the kasbah has the advantage of having heavy walled construction with its inherent thermal mass mediating temperature fluctuations.
Lying south of the Sahara, the Sahel is a vast, semi-arid region that forms a transitional zone between the desert and dry tropical climates. While largely earth and sand, an increasing amount of vegetation colonises the barren landscape. As with desert regions, shade is vital to Sahelian inhabitants.
In these harsh arid climates, grasses, the sturdiest of vegetation, are found everywhere, even in conditions where other plants fail. Mostly non-structural, grasses are commonly used for roofing where they are cut by hand, bundled and tied. Laid on thin timber frames, the resulting thatch is lightweight, waterproof and insulates against the sun. Thatched roofs are built up in layers. In northern Senegal I ate cassava stew in a hut with a thatched roof built from three layers, supplemented by sacking on the underside to provide additional protection against the rainy season.
Many Senegalese structures have no walls to encourage airflow, while others have thin walls constructed from woven grasses stretched between timber frames. In the West there is a tendency to ‘overbuild’ by sizing structures to exceed the everyday live load requirements from people, wind etc. As a result, these buildings tend to last. In poorer African countries buildings tend to be ‘underbuilt’, if finished at all. This is partly due to structures being temporary, partly due to lack of resources and partly to protect inhabitants during failure.
The biggest problem faced by African builders is the dead load of the roof, its weight carried by supporting walls.The resulting movement is often left untreated, so buildings continue to be occupied until they eventual collapse. In the West, the solution to this problem is often to triangulate the roof structure using a tie beam. However in Africa, walls tend to be much lower, with the roof used as head room.
It is far more common to employ lightweight thatched roofs so when failure occurs (as a result of the rainy season), the problem area can be quickly rebuilt. Often, replacement roofs are erected on the ground, ready to be lifted on to walls when the existing structure fails.
The tropical savannah climates have a pronounced dry season, with the driest month experiencing precipitation of less than 100mm (by contrast, the rainy season can experience up to 600mm of rain in a month). Most places that have this climate are found at the outer margins of the tropical zone.
As with Sahelian climates, mud and grasses are the most readily available building materials.When wet, mud is incredibly malleable and capable of producing wonderful forms built up using handfuls of the material. When evaporation causes the mud to dry, the soil shrinks, bringing layers of mud together in compression and strengthening the structure.
In northern Ghana, the Ivory Coast and Burkina Faso, individual huts are linked together with mud walls to create compounds. These villages consist of conical moulded huts for sleeping, cooking and washing as well as huts for food and livestock. Everything in these villages is created with mud including walled thresholds, seats and shelves.
Other conical solid mud towers contain the ashes of the recently deceased. Honoured with liquid food, the columns are allowed to collapse with time and so the deceased are returned to their ancestors. In the town of Nangodi in Ghana, the location of the new walled village is the responsibility of a land priest called the tendaana, who approves requested sites and helps lay the foundations of each new structure.
One advantage of brick construction is that some spaces can be left to create vents. To create basic bricks, mud, water and straw are moulded by hand into rough cubes and left in the sun to dry. Wealthier communities fashion bricks using wooden casing or even metal vices to produce a more standardised shape with sharper edges. The bricks are then either stacked directly on top of each other or staggered, creating circular or rectangular structures, and additional mud is sometimes used as mortar. The entire structure is then finished with a plaster of mud and straw.