Image Shigeru Suzuki built his house in Tokyo both as a residence and as a showroom of sorts for the surging tiny-home trend in Japan. Mr. Suzuki installed a ladder to a lofted sleeping area.

Kominuro Design found opportunities within fire codes to maximize a tiny lot, building a vertical, 645-square-foot plan.

Japan has a glut of abandoned homes in rural areas and small towns. Government officials are auctioning them off for as little as $500. Americans are getting in on the deal. With home prices and ...