The next principle is repairability

The next principle is repairability, the core component of many existing buildings. It states that repairing architectures is in preference to rebuild ones. For instance, a broken wooden window can be repaired (Carroon, 2010), which is as the same as buildings. In contemporary society, few houses are torn down, people prefer to renovate buildings or transform the facades because the expenditure of rebuilding and the negative effects on surroundings are huge (Carroon, 2010). The building should be torn down at first, and then it has to be reconstructed which will make large noise to nearby residents. However, if the function of a building changes, workers could only rebuild rooms which need to be changed without changing the whole structure of the building. This is a method that can not only save the cost but also reduce the workload of workmen. From this, a new conception, ‘down-cycling’, is mentioned. It is different from cycling. Down-cycling means that a material has lost its original functions but has other basic functions with lower qualities, while cycling is the product can be reused as the same product. When being used in reality, those hard produced energy resources can be used in different ways several times with another format, such as greywater (AI-Jayyousi, 2004).