Hexagonal shape architecture

Have you ever noticed the truth that Japanese historical buildings were rectangular shapes? There are so many of combinations of various rectangular shapes. But these are complex consisted with several rectangular buildings and hallways which connect them. So, Japanese complex buildings are all combinations of several rectangular buildings. It's same as the main castle towers, palaces, and farmer's houses.

Isn't there any non-rectangular building? The answer is 'exist', there are hexagonal shapes, octagonal shapes, and other a little bit non-rectangular shapes. Furthermore, if the grounds were not rectangular shapes, buildings were also made in accordance with the grounds. 

However, rectangular shape buildings gained overwhelming dominance until the end of the feudal period. The reason was that they were all wooden buildings. 

Then, why Japanese historical wooden-buildings were made in rectangular shape. Because structures of them was a combination of regularly placed wooden pillars and wooden beams. Conversely, pillars and beams were needed to be arranged regularly according to the structural mechanics valid at that time. If someone tried to make for example orbicular shape or hexagonal shape, he needed to make deformed pillars and beams, also needed to invent new structural method. 

On the other hand, at least, on the aspect of structural mechanics, European historical masonry-buildings would not have such rule. The main reason was their walls were usually made by stone not by wooden pillars and planks. European people didn't need to consider the combination of regularly placed wooden pillars and wooden beams. When they considered the combination, the meaning differed. For example, they wanted to build a religiously mystical interiors, or a majestic floor plans. 

However, several hexagonal shape historical buildings which were technically quite difficult were survived in Japan. These buildings were constructed in the feudal period. As we've mentioned, in this period, they didn't have the knowledge to make non-rectangular shape. How they found the knowledge? And, how they completed?  We will explain some buildings below. If we would say one thing, these buildings were peculiar when they were born.    

Jzo-do(地蔵堂)  

or a Buddhist building enshrined Jzo (one of Buddhist saints) :Shiga(滋賀) Pref. Konan(甲南) Town

 

This hexagonal shape architecture is standing at a corner of a small village. It is standing in the corner of a cross and there aren't any other surroundings. So it is quite eye-catching but doesn't have dignity in our impression. From a historic perspective, it doesn't seem an important property. 

However, there is no hexagonal shape building around, so, it attracts people's attention very much.

According to a record, it was built at 1788 (approximately 230 years ago). The roof is made of 'Kawara(瓦)' or Japanese traditional roof tile. And the building is dually covered by them. It makes the building looking dignified. The building is one-story and a 'Jizo-bosatsu(地蔵菩薩)' Buddhist image is enshrined inside it. However, we cannot look at the image, and only the festival time, we can worship it face to face. 

Choho-ji(頂法寺) temple main hall 

(known as Rokkaku-do(六角堂), Hexagonal shape main hall): Kyoto(京都) Pref. Kyoto City

This hexagonal shape main hall has been existing since a very long time ago. To be more precise, the establishment was later half of 10th century. The oldest record of its existence was written 11th century. It was destroyed very many times because it is located in a center area of Kyoto city and many conflicts at Kyoto city caused the collapses. As much as confirmed as records, the collapses happened 18 times.

The current structure was built at 1877 (approximately 140 years ago). So we doubt the shape is same as the first appeared building or not. The roof is covered with tiles. And in front of this main structure, rectangular shape hall of worship is connected. We cannot enter the inside of the main structure, so, we suppose that even though this building is big, it is also a one-story building. 

We can enter only the front hall of worship. The space is expanded into the main hall, so, one third of the projected area of the main hall's roof is used as a worship space. The area for the main Buddhist image is not pure hexagonal shape. 

It was the birthplace of a famous flower arrangement school, 'Ikenobo(池坊)'. There are fashionable buildings surrounding the main hall. From the upper floors, you can see the pure hexagonal shape roof of the main hall. The precincts are occupied by these buildings, so, there is little extra area in this temple.  

Sazae hall(さざえ堂) 

(or turban-shell-shape Buddhist hall) :Fukushima(福島) Pref. Aizu-wakamatsu(会津若松) City

This hexagonal shape architecture isn't famous as its hexagonal shape but as its unique architectural structure, a double helix. Do you know a double helix? It's amazing that certain Japanese historic building has a double helix structure. 

When it was made, it was an amusement facility for religious experience but a hall to enshrine Buddhist images. 

The helix slopes from the entrance go up and rotate gently. These were not spiral stairs but ramps. Along the slopes, 33 Buddhist images were enshrined. These 33 Buddhist images were called '33 Kan-non(観音) of the western country.' 'Kan-non' is the ultimate Buddha. And the real meaning of 'the western country' is the Buddhist heaven but usually considered 33 temples in a distant region. So people at that time visited this architecture and worshiped 33 Kan-non images. Through this visiting and without visiting many temples in a distant region, they could experience the religious experience. 

By the way, the helix slopes finished the highest point and people went down another helix slopes to the exit at the ground level. People visited this facility weren't disturbed by other worshippers at all. Kan-non images were removed, so, there are only slopes now.

It was built at 1796 (approximately 220 years ago). The roof is made of 'Kawara' or Japanese traditional roof tile. The tower is connected with the entrance expansion. From the outside, you can find how the tower is organized with 3 tiers' helix. The height is 16.5 meters, so, it's lower than usual three-storied pagodas of Japanese temples.

Helix building construction which was used in this tower is the only example among the historical buildings in Japan. We don't know much about the reality, but even if you look around the world, buildings using helix building construction are rear. For example, in a French castle, there is the famous helix staircase planed by Leonardo da Vinci.

According to the commentary in its website, the planner got the Leonardo da Vinci's blue print from an unknown route. However, it's only one of the hypotheses. And nobody knows the truth. Either way the way of Japanese traditional wooden structures was too different to the method in Europe. We respect the master carpenter of this architecture.