There are two fundamental problems with cement: first, it is very expensive, and second, it is incredibly energy intensive to produce, making it quite harmful to the environment.
Cement is expensive all over the world, but it is especially expensive in Rwanda. This is because most cement is imported, and Rwanda’s landlocked geography raises transportation costs of a heavy material. The high price of cement in Rwanda is a key reason that most floors are made with very little cement and very thin pours, which is a reason that almost all concrete floors in Rwandan villages crack. While a cracked floor with cement is nearly impossible to repair, an earthen floor without cement can easily be repaired and re-sealed.
Cement and concrete are also responsible for 5% of global carbon emissions. Cement is the second most used material in the world, after water, and requires significant energy to produce. Meanwhile, earthen floors have 90% less embedded energy and are structurally strong, waterproof, and abrasion resistant. There are significantly more environmentally sustainable building materials than cement, and part of our mission is to put the developing world on a more sustainable development path.