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Building Technology
For hundreds of years there has been little revolution
in the construction industry in terms of design
and materials. As Professor Mitch Gohnert of the
University of Witwatersrand (WITS) states, “to change
the way we build we need to consider both the design
and materials”. WITS masters student Vanja Bulovic
took these words to heart and decided to do her
thesis on sustainable low-cost housing with different
materials and not necessarily using conventional
designs.
Since some 30% of the building cost in standard houses
is spent on the roofing structure, which does not add to
living space, Bulovic theorised that it would be possible
to reduce the cost by also using roofing space for living
space. This led her to designs featuring an inverted
catenary curve to produce a curved roof that holds its
own weight under perfect compression.
In practice she was able to produce the design by using
Hydraform interlocking blocks. This resulted in still more
cost savings through the shorter construction time and only
needing mortar in 30% of the structure. The Hydraform
splitter brick was then used to build the curved roof structure.
The house Bulovic constructed at WITS has an area of
around 75m
2
– almost double that offered by current low-
cost housing. As it stands, and without factoring in labour
and finishings, the dwelling cost just under US $10 000
to construct. The dwelling is being tested for thermal
efficiency and is expected to perform significantly better
than conventional brick-and-mortar structures.
Hydraform’s hope is that, once fully tested, the WITS
Hydraform house can be replicated in any developing
country. Further cost advantages could be gained by
involving communities in the production of blocks and
construction, thereby also creating jobs.
The future of
construction?
To build a sustainable future, we need new and
innovative methods of construction in developing
nations. Hydraform may have the answer.
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