JISC Design Competition 2020 Book

Jos, Plateau State, Nigeria
Construction Process
Excavation is performed for construction of the ground support. The thickness of the excavation is based
on the soil, thickness of the foundation and the type of wall construction. A simple concrete bed of suitable
mix is poured into the excavated area. Once the foundation layer is dried, the brick work is started. The firstclass
bricks with cement mortar of 1:4 ratio are used. This is sufficient to transfer the loads to the foundation
safely. The laying of the bricks must be done only after wetting them. Simple stretcher bond is used when laying
bricks and every course should be truly horizontal, walls should be truly in plumb. Vertical joints of consecutive
courses should not come directly over one another, vertical joints in the alternate course should come directly
over one another. No damaged or broken bricks should be used. Closers should be of clean-cut bricks and should
be placed near the ends of walls but not at the other edge. Mortar joints should not exceed 6mm in thickness and
joints should be fully filled with mortar. Brickwork should be carried out for not more than 1 meter or 3 feet in
height at a time. So as to maintain the shape of the building especially the cylindrical shape adobe building type.
Thatched roof starts with an underlying structure constructed with timber. 2x3inch well-seasoned timber tie
beams are placed horizontally across each other on wall. King posts are nailed side by side to tie beams. Rafters
are placed at an appropriate angle and nailed to the king posts and tie beams. Timber struts are nailed to rafters
and kingpost and braced together. Purlins are placed and nailed above the rafter to have a stable roof. Dried
reeds and straws are harvested from a local source. The best reeds and straw are harvested during the dry season.
This ensures that the reed and straw plant will grow in its place the following year. Reeds and straws are gathered
into bundles about 8inches in diameter and then twisted twice to hold them together until is placeable. Starting
at the bottom corner on one side of the roof, wire and pliers to wire one bunch of reeds and straws at a time to
the cross members, minimal space should be left between each thatch bunch. This process is continued all the
way to the ridge pole, making sure to overlap each upper layer of thatching. A waterproof membrane is placed on
roof member thatching.
JINKAI Initiative Shelter Competition
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