A minka house that has been restored by architect Takumi Osawa and relocated to Kanagawa prefecture, near Tokyo.

A minka house that has been restored by architect Takumi Osawa and relocated to Kanagawa prefecture, near Tokyo.

 Photographer: Noriko Hayashi/Bloomberg

Recycling Our Cities, One Building at a Time

From abandoned Japanese farmhouses to retired New York City water towers, builders are mining existing structures for materials to make new buildings greener.

Takumi Osawa kneels on the narrow balcony of a wooden house outside Tokyo and describes how, 140 years ago, workers would have hoisted baskets of mulberry leaves to the second floor to feed silkworms. When they ate, it sounded like rain.

Known in Japan as minka, these locally crafted structures with characteristic pitched roofs were built for hundreds of years to accommodate farmers, artisans and merchants. This one was originally constructed in 1879 and housed a family on the first floor who tended silkworms on the second and third. Minka are typically designed like an interlocking puzzle, without nails or screws, which allowed Osawa and a team of craftsmen to take the building apart, move it about 90 kilometers (56 miles) east and reassemble it closer to Tokyo, where a couple now live in it.