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Architectural Cultural Heritage Asset
Preliminary Public Record
Date: 2026-06-10
Asset ID
22-ACH-001
Title
Hatchobori Ouan
Status
Preliminary Public Record Version 1
Purpose
This record serves as the initial public documentation of Hatchobori Sakura-an, a contemporary urban residence located in Chuo-ku, Tokyo, Japan.
The purpose of this archive is not to claim value, but to preserve, organize, and disclose historical records, publications, cultural connections, architectural significance, and human experiences associated with the work.
Overview
Hatchobori Ouan is a small urban residence designed by architect Ken Yokogawa and completed in December 2006 in Chuo-ku, Tokyo.
The residence later became recognized through multiple architectural publications, public media exposure, academic selection, international architectural exchange activities, and long-term preservation efforts.
The owner resided in the house and has continued to preserve records, materials, memories, and related assets associated with the project.
Architectural Record
Project Name
Hatchobori Ouan
Location
Chuo-ku, Tokyo, Japan
Architect
Ken Yokogawa
Completion
December 2006
Structure
Steel Construction
Site Area
40.98㎡
Total Floor Area
108.26㎡
Publication Record
Confirmed publications currently identified include:
Housing Special Issue
December 2007
MY HOME 100 Selections
Vol.9
Sumai no Sekkei
December 2009
Architectural Institute of Japan
Selected Architectural Designs 2011
Housing 2000–2010
Shinkenchiku Special Edition
December 2010
Academic Recognition
Hatchobori Ouan was selected for inclusion in the Architectural Institute of Japan Selected Architectural Designs 2011.
This selection represents one of the most important currently confirmed records associated with the project and demonstrates that the residence was recognized within the academic and professional architectural community in Japan.
Media Record
The residence was featured on the long-running Japanese television architecture program:
Watanabe Atsushi’s House Exploration
(Television Asahi)
According to the owner’s record, the residence was visited, documented, and later broadcast by the television program shortly after completion.
Additional broadcast documentation remains under collection and verification.
International Architectural Exchange Record
According to the owner’s firsthand record, Hatchobori Sakura-an was opened to visitors as part of an architectural tour associated with the UIA 2011 Tokyo Congress and the Open! Architecture program.
The owner personally attended the event and welcomed architects and visitors from Japan and abroad.
Related materials currently identified include:
UIA 2011 Tokyo organizational records
Open! Architecture committee materials
UIA-related business cards and documents
Further archival investigation is ongoing.
Influence and Legacy
One of the most significant records associated with Hatchobori Sakura-an is its documented influence on subsequent architectural projects.
According to the owner’s record, an individual who encountered the residence became sufficiently inspired to seek out architect Ken Yokogawa directly and commission a new residential project.
A new residence was subsequently designed and built.
This represents an example of architectural influence extending beyond the original work itself.
Human Experience
Beyond architecture, publications, and public recognition, Hatchobori Sakura-an represents a lived human environment.
The residence functioned as a place of daily life, memory, learning, architectural dialogue, international exchange, and personal development.
The owner considers the residence an important chapter within a lifelong exploration of architecture, culture, experience, and value creation.
Preservation Record
The residence continues to be maintained through periodic professional cleaning, repair, and preservation activities.
According to the owner, comprehensive maintenance is performed approximately every two to three years in order to preserve the original architectural quality and appearance of the work.
Future Direction
The purpose of this archive is to establish a long-term public record that may assist future researchers, architects, students, cultural historians, and visitors seeking information about the residence.
This archive remains under continuous development.
Additional publications, photographs, architectural records, television documentation, UIA materials, and preservation records will be added as they are identified and verified.
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