Changes to Gasshō-Style Houses over Time
Gasshō-style houses were built in Shirakawa-gō and Gokayama for about 250 years, from at least the early eighteenth century until the 1950s. The houses have always had their characteristic triangular roofs, but over time they have changed significantly in other ways.
One example is the evolution of their interior layout. A major difference between the oldest house in the museum (the Former Yamashita Harurō House, built in the mid-1700s) and later houses is the addition of a guest room with a tokonoma alcove. Such rooms were not adopted in Shirakawa-gō until the late 1800s. They frequently had their own entrances and were used to house important guests. An example can be seen in the Wada House, where the family often received high-ranking visitors and even samurai as part of their governmental duties.
Furthermore, while earlier homes were centered around a large, central room called an oe, where the family cooked, ate, and performed many daily activities, later homes are divided into an increased number of smaller rooms. Many also have engawa verandas.
After Japan opened its ports to the West in 1854, the houses evolved further in response to the growing silk trade. Shirakawa-gō residents needed more temperature-controlled workspaces to expand their sericulture industry, and that necessitated larger attics. Later gasshō-style houses, therefore, employed teppōbari (thick roof beams with gentle curves at their ends). Teppōbari could support larger attics, and they also raised the height of the eaves, which is advantageous during heavy snowfall.
Although the body frames of gasshō-style houses were built by professional carpenters from outside the village, the use of teppōbari is thought to have been devised locally by the villagers and carpenters working together.
