atsumasa tamura design office has renovated a 70 year old house in wakayama prefecture, japan, seamlessly blending new and modern elements into the traditional architecture of the building. originally used as a structure to teach tea ceremony, the building had since fell into disrepair. despite this, the owner chose to retain and restore the original characteristics of the building rather than build from scratch.

before the renovation: the house was originally used to teach tea ceremony



called the ‘koumori-an’ house, the renovation was carried out under the concept of ‘value in keeping’. although not iconic or outstanding in presentation, atsumasa tamura design office was concerned with preserving the more traditional features of the house as architectural elements that have influenced the landscape and memory of the village. their plan was to change not the style of house, but rather the style of life that it would accommodate.

although not iconic in presentation, the studio was concerned with preserving the traditional features of the house



this union of old and new is achieved by constructing a new, modern extension to expand the single storey house while refurbishing the internal shell of the original. in order to create a harmonious relationship between the two spaces, the extension was built using the traditional japanese measurements of ‘shaku’, ‘sun’ and ‘bu’ rather than the modern metric system — a ‘shaku’ being roughly equivalent to a foot. as a result, the perspectives and dimensions of the two spaces align and the addition blends into and merges with the traditional structure.

the interior spaces are unified under traditional japanese metrics



the original kirizuma roof is restored and the confining peripheral walls of the site are removed, opening the house to the street. an ultra modern black façade is accented by wooden paneling used on the garage, window frames and gutters. the wooden features continue to the interior where sharp modern lines interact constantly with the ornate remnants of the old school.

the sharp modern lines of the interior interact constantly with the ornate remnants of the old school



an open and spacious terrace is arranged in the middle of the house’s complex, marking the intersection between the old building and the new. exposed to the elements, the terrace invite the outdoors in, and creates a sense of unison between the two worlds. standing on its wooden deck, visitors can observe the differences and similarities between the two spaces, reestablishing the firm’s concept of ‘value in keeping’.

the original kirizuma roof is restored and the confining peripheral walls of the site are removed

an open and spacious terrace is arranged in the middle of the house’s complex

intending to invite the outdoors in, the terrace creates a sense of unison between the two worlds

this liminal space reestablishes the firm’s concept of ‘value in keeping’

before the renovation: plan S=1/150 & after the renovation: plan S=1/150

detailed section plan for unifying the inside measurement of the opening S=1/15

field drawing: the firm completed a detailed survey of the field due to the absence of a print for the 70 year old house


project info:


project name: koumori-an 1945-2015
architect firm: atsumasa tamura design office
lead architects: atsumasa tamura
project location: wakayama, japan
completion year: january 2016
construction classification: renovation
structure scale: single-story wooden building
site area: 256.13㎡
building area: 153.54㎡
total floor space: 152.67㎡
design period: march 2014 〜 october, 2015
construction period: may 2014 〜 december, 2016
air conditioning + kitchen facilities: panasonic
lighting: yamagiwa
water faucets: fonte trading
kitchen: tanico
photo credits: sohei terui



designboom has received this project from our ‘DIY submissions‘ feature, where we welcome our readers to submit their own work for publication. see more project submissions from our readers here.


edited by: peter corboy | designboom

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