Traditional roof in Japanese architecture

TRADITIONAL ROOF IN JAPANESE ARCHITECTURE

The features of Japanese traditional roof

The beauty of Japanese traditional house is most evident in the roof, with curves are sculptured elaborately.
The Japanese climate often rain heavily, so the roof is designed quite wide so that the rain water is not splashed into the house. The roof is slope downwards for the rain water can be escaped easily. In the winter, snow falls to the ground by the slope quickly, the roof isn’t heavy.
On sunny or dry days, the Japanese can open the rain covered installed outside the house, so their living is closer to the nature.
In Japanese architecture, the roof truss is rarely used.

Roof material in Japanese architecture

The roof in traditional architecture is made by heavy wood, and the weight of the roof will help to fix the structure.
The materials are used to make the roof are bamboo, wood, tile, metal, stone.

The types of Japanese traditional roof

Japanese architecture has 3 types of roof, are: Kirizuma (gabled roof), Yosemune (hipped roof), Irimoya (hip-and-gable roof).

• Kirizuma roof (Gassho-zukuri)

Gassho-zukuri architectural style means “praying hands”. The roof of this style slopes down likes 2 side of the triangle or book overturned. Two sloping roofs knit together, the top is like the mountain peak.

The roof is covered by thatched, straw with 50cm in thickness. The slope roof helps the snow falls down easily.  The roof is designed to rotate to the direction of the light, so snow melts easily.
With this roof, we can utilise the above space to use.
The Gasshi style houses are built in snowy regions, rural areas and for building temples.

• Yosemune roof

The Yosemune style roof is popular with Japanese farmers. The roof slopes down 4 sides, usually built on horizontally rectangular houses. The slopes of the roof form the rectangular shape on the long side of the house, and form the triangular shape on the short side of the house. The length of each edge from the top to the four corners affects the slope of the side. If the angle is bisected into two 45 degrees, it’s called “masumi”. If the angle is unevenly devided, it’s called “furezumi”.

When the roof was built in the square house or the houses with the depth greater than the length, the length of the roof edge must be adjusted so that the angle bisected to 45 degrees.
This is the typical architecture style in Ibaraki countryside. This roof is often found in padora or temples.
The roof is covered by straw, thatched, tile.

• Irimoya roof

Irimoya roof is the combination of Kirizuma roof and Yosemune roof. This roof has two floors, a small upstair, slopes 2 directions: back & front, built in Kirizuma style, suitable for snowy areas. The downstair is larger, slopes 4 directions: back, front, left, right, built in Yosemune style, provide the stability for the building. This roof is suitable for strong wind areas.
Irimoya roof is often used for temples and rich families.