Alternative raw material: Used diapers as building material for houses
First on the baby, then on the construction site: used diapers can be recycled in parts of the house (right).
Source: Getty Images/Stephanie Neal Photography; Muhammad Arief Irfan/Springer Nature/dpa
It sounds bizarre, but it would save resources and protect the environment: Researchers have investigated whether used diapers can be reused as a material in house construction. In fact, they could replace a certain raw material – but not equally for all parts of the house.
An the search for environmentally friendly building materials, scientists have landed on used diapers. Washed, disinfected and shredded, they could replace up to 27 percent of the sand in the concrete and up to 40 percent of the sand in the mortar in structural parts of a one-story house, writes a research group led by Siswanti Zuraida from the University of Kitakyushu (Japan). in the journal “Scientific Reports”. The building regulations in Indonesia were used as a basis.
“Building materials are often the most significant physical contribution to the construction of homes and can account for up to 80 percent of the total value of a basic dwelling,” the authors write. Cost is the first barrier to sustainable construction in low- and middle-income countries.
Due to the annual population growth of 4.1 percent, around 780,000 new housing units are needed in Indonesia every year, but the construction industry can only create a maximum of 500,000. Zuraida and colleagues therefore tested an alternative construction material with the used diapers, which would also relieve landfill sites.
To do this, they made concrete mixtures with different proportions of diapers instead of sand. They allowed the mixtures to cure for 28 days and tested their compressive strength. Using Indonesian building codes, they then determined which parts of the house could hold what proportion of diapers without sacrificing the strength needed.
In a three-storey house, the compressive strength of the load-bearing elements, such as pillars and beams, must not fall below 20 megapascals. That is why the fine grain content in them can be replaced by diapers up to a maximum of ten percent. It is up to 19 percent for a two-story house and up to 27 percent for a one-story house.
In masonry, non-load-bearing walls, on the other hand, the proportion of diapers in the mortar can rise to 40 percent. In the mortar for floor slabs, in the house or on the terrace, diapers can replace up to nine percent of the sand.
Zuraida and colleagues calculated that for a 36 square meter house with a building material requirement of 22.79 cubic meters, 1.73 cubic meters of diaper waste can be used. However, this is not easy to implement in Indonesia. On the one hand, there are no companies there that use disposable diapers as recycling material. On the other hand, the country’s current building regulations would prevent the use of diapers in concrete and mortar.
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