Our design proposal would be a stepping-stone towards the creation of a densely populated, but highly livable, neighbourhood. It is intended for a mild climate and a culture that has a tradition of courtyard housing, so it is most probably located in Africa.
To begin, a sloped area of land with a relatively deep layer of natural soil is needed. This could be provided by a sponsoring agency, or perhaps a group of existing residents is persuaded to take-up a temporary residence, demolish their substandard homes, and offer their land and labour, in exchange for the chance at building a higher quality of life.
The land parcel must be large enough, at least 1000 s.m., to enable the excavation of a new road loop, founded about 75 cm. below average grade, so as to provide positive surface drainage for the project area. The work could be done manually, and would yield an initial supply of raw earth for the manufacture of CEBs.
This approach answers one of the main criticisms of CEB technology: that the mining for the soil creates unsightly, and potentially mosquito-infested, remote excavation pits, as well as entailing high transportation costs.
The land in the centre of the loop would then be subdivided into individual lots. In our proposal there are twelve lots, 4.5 m. wide by 9 m. deep. These would provide additional earth sufficient to complete a fully developed block of single-storey buildings.
The Phase 1 building program is the construction of three small 4-square CEB buildings, at the intersections of four lots. These will provide the initial accommodation for the 12 owners, each in their own $300 house, with shared walls between them. It will give good quality shelter, a high level of security, and a home-base for obtaining financial stability.
There have been several kinds of CEB suggested in this competition. Many could be useful for the concept; but that would depend greatly on where the project is actually located.
We have chosen the i-Brick process, developed by an African company, Ikhaya Brick Technologies Pty. It appears to produce an extremely high strength and durable compressed earth brick, with published material properties. The required clay content is very low, making 95% of African soils suitable for use. Also important for this competition, the cost (not including earth or labour) is known, at up to USD 0.30 per brick, when used for a large production run.
Earth-brick technology is very similar to traditional adobe-brick construction. Many local techniques for stacking bricks, to make arches, parapets, and other building features, could be easily adapted for use and decorative purposes.
PHASES 2, 3 & 4
Over time, the owners can take advantage of the surplus earth available on their lot, and their acquired skills, to build additions, at a similar low cost. This will represent a continuing opportunity to improve their standard of life, provide possibilities for rental income, and increase the value of their holdings.
Phases 2, 3 & 4, lead to the eventual development of a complete block of single-storey courtyard houses, each individual house growing almost 600% to approximately 29 s.m. of gross floor area. With a second level added, the potential would be for a home that approaches first-world standards in size.
The courtyard house is the traditional housing form for a great many of the cultures now suffering the brunt of rapid urbanization and overpopulation. But the project could be many other buildings types too, including mid-rise apartment blocks, where appropriate.
The buildings could be retro-fitted with electrical and/or plumbing conduits quite easily. The i-Brick is manufactured with holes that align vertically, which can be accessed after construction.