Restoration Research Taiwan Governor's Office Monopoly Bureau Taichung Branch Re-drying Chamber Of Historic Buildings

Tobacco was original from the Americas and it was brought to the Philippines by the Spanish before being spread to Guangdong in China,and later on it was brought to Taiwan by immigrants.By the time when the species of tobacco changed from China species to yellow species tobacco from the United States,the processing procedures of tobacco acquired through contract production from the four major tobacco planting areas.Monopoly Bureau of the Taiwan Governor's Office established two associated re-drying chambers and three dedicated re-drying fields in total during Japanese occupation period.The age of attached re-drying chambers ended and they were replaced by the independent re-drying field.The original attached tobacco re-drying chamber was moved to dedicated-built re-drying chamber,and its layout upgraded along with the prosperous tobacco business.The additions of building width and length expansion were for placing additional re-drying machines,the outreach power room and the cooling and moisture venting pipes only for re-drying machines rugged out the roof plus the modified Osaka transom window installed on the roof created the identity and architecture features of the re-drying chamber.The re-drying procedure on the tobacco leaves after initial drying would be able to advance the flavor of the tobacco as well as avoid them going moldy and rot.The critical equipment,re-drying machine,was it consisted of functional tanks for drying,cooling and moistening.The brewery factory of Taichung branch in Japanese occupation period,the re-drying operation group buildings included re-drying chambers,tobacco leaves and tobacco warehouses,and operational field.The first construction of the re-drying chamber was built in 1933 and additional buildings were built in 1938 before it reached the scale of two drying machines and three compressors.The existing historic building at the moment is the south part of the re-drying chamber.Checked the historic files of Monopoly Bureau of the Taiwan Governor's Office,and the materials of re-drying chamber used for construction were Japanese fir and Taiwan.The building in the south section of the old re-drying chamber is the one and the only one survived and it registered as a historic building.Complying with the principles of authenticity,reversibility and dissemination regulated by the Venice Charter,and carried on with the rehabilitation design.In terms of scientificity,instrument was used for non-destructive testing on wooden material and classified the structure of the whole house into three types for large timber mechanical analysis.The degree of damage proposed was divided into three levelsreservation,maintenance and replacement.The wood components that were damaged seriously were replaced with Alaska cedar.Wood threshold and between pilasters used improvement method.External angle bracing was restored according to the original wood material used.Bamboo-mud-walls,weatherboards,metal house surface plate,and windows were repaired by the original engineering methods.The material selection for large timber structure was based on the top material defined on production material classification.ACQ agent was injected into the material used for threshold in high pressure after needling.In the purpose of termite-proof,monitoring stations were set up around the buildings,and Hexaflumuron underground bait stations were installed after the completion of the construction for prevention.The contacting areas between wood materials and construction were coated with creosote and ACQ before being covered by cooper strips for damp proof;the horizontal beams and joggle joints for rafters of the large timber house frame were mainly moldboard joints and they were replication;lime work preparation was done in advance for the use in the final construction surface of bamboo-mud-walls;in conclusion,the engineering process of the historic building rehabilitation from the beginning to the end was recorded in a written document as the reference for future wood construction restoration as well as for the evidence of the important segments on the re-drying facility in tobacco industry.