Zero km. House
Zero km. House
Zero km. House
in Ghana, Butre
Year: 01/2023 - xxxx
Type: Rammed earth & Wattle incl. Daub Walls
Location: Ghana, Butre
Our first project in Ghana, the Zero km house, demonstrates that it's possible to build a structure entirely from locally available materials sourced from the nearest area. Simultaneously, we are using this challenge as an opportunity to develop a type of building that thrives in Ghana's humid-hot climate, merges traditional building methods with modern design, and represents a solution for affordable housing. In the future, the Zero Km House will be the main building of the Isopterra Earth Building Center in Butre. It will be used for workshops, training programs and support offerings for the local community and small enterprises.
The entire project, from the initial idea to the final construction, was completed by committed students in their free time outside of their studies. They handled everything from the design and raising funds to the hands-on construction at the site. A key part of the project was working closely with the local community. There was a strong exchange of knowledge between the students and the local builders of the community. All participants learned a lot about earth construction through this project and are now able to use these skills on other construction sites. This sharing of skills is important for helping the building industry in Ghana grow in a way that uses local techniques and improves skills. The house itself got a lot of attention and led to more projects that are focused on being sustainable.
“Support us”
CONCEPT.
The design is based on a building module that can be combined in different ways, depending on the environment where the house is located. The combination possibilities fall under the theme of "Urban, Rural, Suburban". In urban areas, the modules are arranged to form a courtyard house, maximizing privacy and shade. In suburban or rural areas, it's either built as a U-shaped structure or as a single unit. In all design options, effective and natural ventilation of the spaces is desirable. Due to the small temperature fluctuations between day and night, it's additionally important to aim for minimal heat storage in the building components and, where possible, to prevent their heating. As this climate often includes long periods of rain, it's essential to protect the building from potential damage through structural safeguards. In many regions, these requirements have led to a preference for using lightweight materials like wood or bamboo.
Most of the walls were made from rammed earth. This natural material is versatile, suitable for both interior and exterior walls, and as flooring indoors. It stands out for its unique look and feel in various shades and acts as a natural, eco-friendly binder with low energy needs. Plus, it's completely recyclable and can be reused directly. Its ability to absorb and release moisture creates a comfortable indoor climate.
The cross walls were built using one of Ghana's traditional mud-building technique called "Wattle and Daub." Wattle and Daub is a method that combines wood and mud. For this, a special, very hard wood from mangroves is used. This wood was chosen because it's resistant to termite attacks.
One of the walls was built with specially made CEBs (Compressed Earth Bricks). The CEB technique offers several significant benefits. Using mechanical presses leads to a big improvement over traditional methods, achieving consistent product quality. Due to the flexibility of this production method in both rural and urban areas, CEB was used as the third mud-building method in the house.
The entire roof structure was made as a bamboo construction. Bamboo is a fast-growing grass found in tropical and temperate regions, growing three times faster than most other plant species. It was chosen for its flexibility and strength.
The roof is designed as a double shed roof with a 150-centimeter-wide overhang. This type is more material and cost-efficient than a traditional saddle roof. Additionally, the top opening on the southwest side helps with airflow, taking advantage of the usual direction of the wind.
The connections were made either with threaded bolts, washers, and nuts or with bamboo dowels, depending on the load. All connections were additionally tied with strong rope.
Butre
The execution site of the project will be in Butre. Butre is close to the coast and is located in the South of the coastal area in Western Region of Ghana.
Butre is a small fishing village located on a sheltered bay by a forest, between the communities of Busua and Asemkaw. Now the village inhabits 400 inhabitants, largely from the Ahanta ethnic group. Butre was among the early historical towns generated by 17th century inter-European and inter-African conflict.
The Western Region has the highest rainfall in Ghana, lush green hills, and fertile soils. The culture is dominated by the Akans.
The main economic activities in present-day Butre are fishing and subsistence farming.
