The 9 Tsubo House was originally designed and built by the late Japanese architect Masuzawa Makoto in 1952. The tsubo is a traditional Japanese unit of measure that equates to two tatami mats placed side by side. A tatami mat is roughly 3′ x 6′ so one tsubo would be 6′ x 6′ or 36 square feet. The 9 Tsubo house, therfore measured 18′ x 18′ for minimalist footprint of only 324 square feet. When a second floor loft is added the total square footage typically ranged from 500 — 540 square feet.
The reason for Makoto choosing these exact dimensions was based on a program offered by the houseing corporation of Japan after World War II. They would only provide loans to those people building a home of 50 square meters or less (~538 square feet). Anyone needing a larger house was assumed to be wealthy enough not to require a loan. Wouldn’t it be great if a US bank had a program like this incentivising people to build smaller homes?
Modern 9 Tsubo Houses by Boo-Hoo-Woo.com
In 2002 a company by the name of Boo-Hoo-Woo decided that this old 9 Tsubo House concept was pretty cool. They assembled 5 current Japanese designers to develop a line of homes all based on the original 9 Tsubo house by Mokoto a half century ago.