SCEBs - University of Colorado Boulder

2.1. SCEB Technology Advantages
The motivation of this thesis is the standardization of earth as an alternative
building material. Concrete has grown into the most important building material over the
last century and in industrialized nations the annual production amounts to 1.5-3 tons per
capita (Glivand, Mathisen, Nielsen; 2005). The use of cement in the production of
concrete contributes vastly to the construction industry‟s carbon footprint.
Cement production is responsible for 10% of global CO2 emissions (Keefe, 2005).
Aggregate is often created by mining, and crushing rock to the desired specifications.
Building sites are rarely located within proximity to the mining sites, necessitating
additional energy requirements to transport the materials. This process requires a huge
amount of “embodied energy”. Embodied energy is the sum of all the various processes
involved to implement a material into production. Keefe (2005) offers an embodied
energy consumption value for various building materials. “Concrete block” registers
600-800 kWh/m 3 and “Earth” registers 5-10 kWh/m 3 , clearly indicating an advantage to
earth building. The addition of cement triggers a chemical reaction which emits
noticeable amounts of carbon dioxide into the atmosphere. One mass unit of cement
generates approximately an equivalent mass unit of CO2 emissions (Glivand, Mathisen,
Nielsen; 2005).
To investigate additional advantages of SCEBs, current research is investigating
the indoor climate regulating effects of structures built from earthen blocks. Minke
(2006) presents data showing that earthen construction materials are able to absorb and
desorb moisture more efficiently than any other building material, allowing them to
regulate indoor climate. He suggests a range of 40-70% relative humidity as ideal for
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