Vernacular architecture highly contributes to sustainable or green buildings. Vernacular architecture is something that has been a part of human evolution. Adobes evolved when humans tried to protect themselves by building using materials available in hand and are found around them. It has lesser impacts on the earth and its environment as they are eco-friendly. Vernacular materials and construction techniques are proven to consume less energy when compared to other materials of the modern world. For all these facts, the world is taking a look back on the vernacular styles and methods to adopt them into their living and practices.
Ghana, a country in West Africa, is known for its various vernacular construction and techniques. Architects of this country constantly strive to adapt and develop building crafts from nature to keep their cultural dogmas alive forever. The architecture of Ghana can be divided into three zones, namely northern, middle and southern zones, as they have distinctive materials and construction techniques of their own.
Materials play a vital role in making the world sustainable and eco -friendly. vernacular architecture- to break it down is simply using the available materials in and around the locality for construction purposes, thus, reducing the travel cost and the pollution caused, resource conservation like coal and fuel,etc. Below is the list of materials used popularly in Ghana Architecture.
The fast-growing bamboo, known for its high tensile strength and low weight, is widely found in Ghana with 25 identified species of native and foreign. Bamboo is made into scaffolding, furniture, panels and boards. In the northern part of Ghana, it is used as a wall structure. It reduces the cost of construction and transportation and is renewable, making it eco-friendly.
Timber is an asset to Ghana for its abundance and is exported to various countries. Its use in Ghana takes the form of both structural and non-structural members: sawn wood, veneer sheets, particle boards, and plywood for both export and indigenous use and as walls and structural frames as structural members. It is known for its durability, fire resistance, and attractive appearance.
Clay bricks are a widely used vernacular material in Ghana. Clay particles are coated with a thin film of water molecules which helps them to balance out the exterior and interior temperature of the buildings. They are environment friendly, locally available, need less manpower, and are energy-efficient materials. It has become one of the most commonly opted materials for suitable or green buildings.
Laterites are all soils and rocks that are reddish-brown due to the residual and non-residual soil of weathered rocks containing rich iron and aluminum. Laterite is one of the best vernacular materials as it is cheap and eco-friendly. As it has greater water holding capacity, it is used for flooring for homes, fills for foundation, and bases for roads. It can also be moulded into bricks, and because of its natural thermal nature, it acts as a coolant to buildings.
This material is used for roofing of various types like the double-pitched, gable-ended, hipped, conical or hemispherical. Thatch is a type of grass that is loosely bundled with twine. It can withstand winds and scour. It is used to reduce heat while using solar radiation.
Construction techniques may be indigenious to the local community or some techniques are found universal. Techniques of construction vary as the materials that are found around the locality vary. People learn to use the materials in different ways. Below listed are the techniques used by the Ghana people for construction purposes.
Wattle and Daub
Wattle and Daub is a popular construction technique in vernacular architecture. It’s a method in which the earth from the site is plastered on skeletal frames acting as structural members and walls of the houses. The horizontal strips are usually made of timber that knit to vertical posts. Ghana’s vernacular architecture slightly differs in this methodology. The site or the profile of the house finalized is marked on the ground using pegs and strings. Later the earth from the marked places of pegs is dug out, and vertical posts are inserted with stone rammed at the base to hold firmly in place.
Wooden strips are interlaced horizontally and vertically, atop which laterite balls are pressed of thickness ranging from 6 to 9 inches, for protection from harsh weather, insects, and animals. The roof is of palm thatch. This construction method is widely found in the rainforest regions of Ghana.
Earth construction, otherwise known as adobe construction, is one of the oldest techniques that have travelled with us for it provides economic and environmental benefits. It is said that 30% of the world’s population live in earth construction houses found most commonly in developing countries and rural areas. It requires less manpower, doesn’t require skilled labour, and reduces material cost as adobe is a low-cost material.
Apart from being beneficial in the reduction of costs, it also has the added advantage of high thermal and acoustical performance. But as its walls are massive, it cannot be built in the seismic zone of Ghana as it can’t withstand earthquakes and can easily collapse. Though they seem highly economical and environmentally friendly, they have disadvantages like maintenance, constant replacement of materials.
This technique can be found on Ghana’s coastal and forest belt and is similar to Wattle and Daub. The grid made of bamboo is laid and is infilled with mud or palm mats. This requires the skill to cut timber precisely in desired sizes and shapes for construction. This method was quite difficult compared to other methods as primaeval Ghana had no mechanical fasteners, yet the locals were skilled in erecting timber structures with their hands.
This technique is considered one important thing to be looked upon as it uses highly environment-friendly wood with advantages like durability, fire resistance, and appearance. In the past 20 years, this timber constructed houses have reduced in Ghana as it requires skilled labour and requires frequent replacement.
Pile dwellings are found in the wetlands or swampy areas of Ghana. They are also called floating dwellings as the structure is lifted entirely by wooden supports, protecting it from the dampness of the ground. Raffia palm trees are used to construct this stilt architecture of Ghana. The raffia posts are inserted into the dug-up holes to lift the structure five feet above the regular water level. Ventilated double roof is used for airflow.
These kinds of constructions are initiated with the climatic conditions of the specific region in mind. They should be able to provide a free flow of vertical movement even with the changing water level underneath. The place where this kind of architecture can be found is in the western region of Ghana.
Rammed Earth / Atakpamé Walls
A technique that is found in the northern part of Ghana where wood is not in abundance. Walls are 300 mm in thickness and have a footing of an average of 45 cm and a height of 2.5 m. Raw materials like soil, gravel, and sand are combined to form a mixture. These materials are highly non-combustible, very durable, and thermally massive. 200 mm diameter laterite balls are moulded.
Five layers are laid separately to a height of 600 mm, each covered with palm leaves. Fan palms are used as marks for lintels. After the last course, posts are inserted at 600mm intervals to act as structural supports for the roof. If it is a flat roof, mud is the choice of material, and if it is a pitched roof, then grass or palm fronds are used. This construction can be done only by skilled locals of the region.
Anon, (n.d.). Available at: https://www.sciencedirect.com/science/article/pii/S2468227620301629.
Anon, (n.d.). Available at: http://ghanarising.blogspot.com/2013/08/tourism-nzulezo-village-western-ghana.html.
Anon, (n.d.). Available at: http://www.naturalbuildingblog.com/rammed-earth-houses-in-ghana/.
Anon, (n.d.). Available at: https://commons.wikimedia.org/wiki/File:Wattle_and_daub_construction.jpg.
Anon, (n.d.). Available at: http://www.africavernaculararchitecture.com/ghana/.
Anon, (n.d.). Available at: https://www.fieldstudyoftheworld.com/painted-earth-architecture-of-the-kassena-people/.
Anon, (n.d.). Available at: https://bambubatu.com/the-best-varieties-of-bamboo-for-building-and-construction/.
Anon, (n.d.). Available at: https://www.build-review.com/understanding-the-booming-popularity-of-timber-construction/.
Anon, (n.d.). Available at: https://robarboring.com/how-to-build-stable-foundations-on-clay/.
Anon, (n.d.). Available at: https://www.indiamart.com/proddetail/laterite-stone-construction-23346765862.html.
Anon, (n.d.). Available at: https://hertsthatcher.com/2015/06/28/preparing-a-thatched-roof-structure/.