The rammed earth Tulou of the Hakka people, China

 
   
     

 
 

These are Tulou, built by the Hakka people of China. The Tulou are massive rectangular (representing Earth) or circular (representing Heaven) fortress walls of rammed earth several meters thick. These buildings have survived since the 17th century demonstrating the durability of rammed earthen structures. Rammed Earth Consulting in the UK are an example of today’s rammed earth builders.

 
 
 
       

Before a Tulou was built the locals would take the advice of a master of Feng Shui to place the building correctly with relation to the hills, trees and the river. The walls of the Tulou consists of a lower section built from stone blocks held together with lime or clay with rammed earth walls on top.  The earth used to build a tulou is mixed with sand, silt from the river, egg white and the starch from sticky rice soup. The walls are re-enforced with horizontal bamboo sticks. The walls were built inclined toward the centre so gravity pushes them together.

The Tulou are three to four storeys high. The bottom two storeys have no outward facing windows as a defensive measure. The thick walls also incorporate escape passages. These homes typically house around 500 people. They are a UNESCO World Heritage site.