The following information was revealed about the reconstruction of main halls. 1. The main reasons for reconstruction of former main halls were deterioration, natural disasters, upgrading of functions and war. 2. The structure of the main hall was wooden in 80%. The use of non-wooden structures peaked in the sixties, but wooden structures have increased again since the eighties nationwide. 3. Reconstruction of main halls could be categorized into those attributable to deterioration, disaster, upgrading functions and no reconstruction. 4. Passing down over many generations and placing importance on tradition will be a guideline for reconstructing the main hall.