3.3.3 On Dismantling and Reassembly Restoration
Article 3.5 in the ICOMOS Charter Principles for the Analysis, Conservation and Structural Restoration of Architectural Heritage pointed out that “Each intervention should be in proportion to the safety objectives set, thus keeping intervention to the minimum to guarantee safety and durability with the least harm to heritage values.”[66]Article 3.15 also declared that “Deteriorated structures whenever possible should be repaired rather than replaced.”[67]However, most of China's architectural heritage uses wood structures which is not easy to sustain for a long period, even with regular preventive maintenance.Article 4 of Qufu Declaration declares that the main disadvantages of Chinese woodframed buildings are that “they are easily decayed, wormed and burned.Decay is the most important problem.The most perishable part of the timber frame is the wooden pillars buried in the walls and roofing wood beams, … The rotted root can easily cause the sinking of the column which will then cause the upper frame to deform, allowing the roof to leak.The result is that the leaking roof will increase the risk of damage to the timber frame.”[68]Therefore, it is not realistic to preserve the original structure when it has serious rot damage.In this case, the decaying materials have to be replaced to ensure the safety of the entire building and any visitors.
In addition, the structures of traditional Chinese wood building are connected by special non-rigid joinery Sunmao and support Dougong without glue or nails, which make the buildings flexible and at the same time make it easy to disassemble, replace and repair.The article 6 in Qufu Declaration stated that “the dismantling of wooden structures is one of the important methods for its restoration.It is a thorough and effective traditional repair method for architectural relics.”[69]But at the same time, the process of dismantling and reassembly restoration should be prudent.It has been found that “this method should [only] be used when the wood structure has deep damage to the whole or key parts and cannot be solved by other methods.”[70]Beijing Document highlighted that “All works should be properly recorded...Replacement timber should be used with due respect to relevant values.New members or parts of members should be made using the same timber species but where this is not feasible, it is essential that the similar characteristics to the original members should be maintained.”[71]In this procedure, any significant material removed from the site should be preserved for research and education.In the Principles for the Conservation of Heritage Sites in China, Article 27 also stated that “Major restoration through complete disassembly of a structure should be avoided as far as possible; … Restoration through disassembly should result in the removal of all unsafe elements and should ensure that no further treatment is necessary for a long period.”[72](https://www.daowen.com)
Disassembling of a wood frame is a traditional conservation method of Chinese architectural relics.This kind of metabolic protection method with respect for the historical information still conforms to the principle of authenticity.Especially for religious architecture, updating the decaying materials and renewal of components are inevitable.At the same time, the process of dismantling and reassembly is also a means to review the ancient architectural crafts to update procedures and increase our understanding of historic construction methods.