Abstract
Repair and renovation works in the building lifetime are usually executed while the buildings are in use and require considerable amount of incident work, and the reduction in incidental work is of great importance. In the case of repair or renovation of some building element, other accompanying elements which must be removed temporarily in advance, are considerd to exist on the "shallow" position to the repaired element Such relation "accessibility hierarchy", can be indicated as a tree chart drawn continuously from the earth to finishes. This chart can clearly indicate a group of accompanying element works in repair and renovation. Planned lifetime of deeper element in the "accessibility hierarchy" should not be shorter than the lifetime of the adjacent shallower element, and the deeper lifetime should be an integer multiple of the shorter one. Longer economic lifetime, having a wide latitude, may be easily adjusted without any specification change. This co-ordination system can synchronize the lifetime of a deeper building element to the adjacent shallower building element lifetime. The preceding life cycle co-ordination system, as. 2^n cycle, can reduce accompaning works and propose a scheduled repair and renovation in building lifetime.
