Sustainable urban dwelling units: Homes for urban poor

Low cost dwellings that are affordable and sustainable have long been the dream of city planners in urban areas of the developing countries, where many of the urban poor are forced to live on streets or in temporary accommodations. The sustainable urban dwelling unit (SUDU) is one such design that aims at achieving environmental as well as economic sustainability in urban areas of poor African countries like Ethiopia by eliminating dependence on imported and expensive building materials like steel and concrete. Ethiopia has few material and financial resources. With an already booming population that is sure to go up tenfold in the coming years, there will be a further increase in demand for safe shelters for the urban poor.

The Sustainable Urban Dwelling Unit (SUDU)

The SUDU is a double story building, made entirely out of locally available stone and soil, resulting in a low cost modest home for the poor. By combining timbrel vaults and compressed earth blocks, an ecologically balanced durable structure can be created without any need for steel, reinforced concrete or wood to support floors, ceilings and roofs.

Soil and stone have less tensile capacity, so building with these materials requires structural solutions based on compression. In SUDU, the construction technique is based on the African usage of cement stabilized and soil pressed bricks, both of which use locally available soil. This method is called compressed earth block (CEB) construction.

The locally available soil is rich in clay particles. The SUDU makes use of rammed earth techniques for constructing the first floor of the building with a 60 cm wide wall structure. The ceilings and floors of the building are constructed using a tiled vaulting technique. In this technique, sun dried tiles are used for the first floor and loam is used for the roof, both made from the same soil. Additionally, this vaulting technique does not require any framework, eliminating dependency on wood. Overall, an eco friendly, sustainable home for the urban poor.