![](bg7.png)
these poles were then bent which gave the rounded to the hut. The third component of the structure is
the torus wrapped in papyrus, this one was a spiraled coil that surrounded the whole house to
consolidate it. The fourth component part of the structure is the supporting pillars, they supported the
hut from the inside and leaned on hooves. These supporting pillars were 8 to 13 depending on the
size of the hut. And finally the whole structure of the hut was covered by thatch while looking for a
beautiful aesthetic effect (Figure 20) [3].
5. Construction materials
Burundi's traditional hut was entirely constructed of plant materials. The materials found mainly
were straw (roof, floor,), bamboo (structure, walls), palm (mat, spiral ceiling), papyrus (ropes,
braided blankets), reed (torus, walls), thorny (piles of the palisade), erythrin (piles of entry) and many
others.
In our case, we will focus more on 2 building materials, straw and bamboo because of their many
qualities and varied applicability nowadays.
In 1994 task group 16 of the Conseil International du Bâtiment (CIB) defined 7 principles for
sustainable construction: Reduce/resource consumption _Reuse/reuse resource_ Recycle/recyclable
resource_ Nature/protect nature_ Toxic/eliminate toxics_ Economics/apply cycle costing_ Quality
[4].
5.1. Straw
Straw which is a well-known material in the traditional architecture of Burundi. Nowadays this
material resurfaces because of its various qualities.
Advantages:
straw is in abundant resource, can be cultivated or it can be just the residue of the cereal plants, is
light which reduces the loads on the foundations, is a good thermal insulator, when the straw of a
building is damaged by moisture, it can be reused as fertilizer for crops, Straw is often a local
building material for this it does not need to be transported long distances which would cause CO2
emissions, can be used in the raw state, it does not need special treatment and is environmentally
friendly and does not release toxin [5].
Limitations:
The big enemy of straw is the water that's why when using the straw to cover the roof we must
ensure a good slope to the frame for a good flow of rainwater. It is also necessary to change the part
of the straw damaged on the frame, since straw is an agricultural product, its compatibility with other
building materials for good finishing is restricted and if straw is not well fixed it can catch fire.
PS Although most people are worried that straw could catch fire easily several studies show that this is not
the case, indeed the fire needs oxygen to spread and when the straw is stacked well it can hardly catch fire [6].
5.2. Bamboo
Advantages:
Bamboo is flexible and easy to handle, is quite resistant and used as structural elements, is not
pollutant and does not release toxin, does not break easily when curved which gives it a great
resistance against the earthquake; can be used for permanent or temporary constructions, is easily
renewable because it grows quickly.
Limitations:
After being cut, the bamboo can be easily attacked by insects so that it must be well dried or
treated, bamboo does not have the same diameter throughout its length but also when it dries its
diameter decreases and it can interfere during construction, when the bamboo is dry it can catch fire
but it can still be treated by fire-resistant substance [7].
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