2019 Volume 84 Issue 763 Pages 1903-1913
The purpose of this study is to reveal the “architectural conditions”, such as structure, building age, historical importance, and changes on size and uses of a building, which will lead architects to their design decision. In this paper, we set our original indicator, “quantitative similarity of the old and the new” and analyze trends and characteristics of retrofit architecture in these several decades. This study will give us important clues on systematizing and generalizing the design method of retrofit architecture.
The subjects of this study are 100 cases of retrofitted modern architecture, which were printed in the magazine, Shinkenchiku, from 1974 to 2017. First, for analysis, we set 7 items as “architectural conditions” and a 19 items as “design decisions”, and both include the item of “the distance between the old and the new”, which is important to each other. Second, we prepared a matrix whose rows are the 100 cases and whose columns are the “architectural conditions” and the “design decisions” and calculated cross-tabulation of all items. In addition, we did Chi-Square test to check its significance.
As for the relationship between the “architectural conditions” and the “design decisions”, especially in a category of “shape”, historical importance is relevant to flatness of façade, height of façade, alignment of façade and shape of window and change on uses is relevant to allocation of façade material and shape of window, ratio of the old and the new has relation to flatness of façade, maximum height, allocation of façade material, key element of façade, shape of window. Items of the “design decisions” in a category of “finishing” has few relation to any items of the “architectural condition”.
Especially as for the relationship between the “architectural conditions” and the “distance between the old and the new”, it has relation to ratio of building area of the old and the new and ratio of total floor area of the old and the new. It has also relation to flatness of façade, shape of roof, maximum height, height of façade, allocation of façade material, key element of façade, alignment of façade and shape of window, which are all in the category of “shape” in the “design decisions”. We can also see relation the “distance between the old and the new” and material of façade and color of joint elements.
Thus we analyzed trends and characteristics of retrofit architecture using an indicator of “quantitative similarity of the old and the new”, and clarified what kind of “architectural conditions” have affected “design decisions”. Through this analysis we find that architects tend to put more importance on “shape” than “finishing” when they think about the combination of the existing part and the new part, and that the “distance between the old and the new” is influenced by the “architectural conditions” and also have affected “design decisions”.
