Roofing​​​​​​​​​​​​​

The curved, sweeping roofs of traditional Japanese architecture are one of its most recognizable and endearing features. They are a prime area of focus on traditional homes, not only for visual appeal, but their functional role and unifying significance to the structure. While the graceful lines are what most eyes focus on first, the real takeaway is the wisdom behind the remarkable structural ingenuity, craftsmanship and performance.

Traditional Japanese roofs are designed to withstand numerous climatic challenges, with some descending close to ground level for greater efficacy in shedding rainwater and dislodging snowdrifts. The deep overhanging eaves protect outside walls and residents alike from the elements, while the weighted design reinforces durability to minimize structural damage in high winds and prevent collapse in earthquakes. There are four main traditional roofing styles that have kept Japanese homeowners safe for centuries:

Eaves

Graceful, extended eaves are another noteworthy feature of traditional Japanese roofs. (Fig. 163) While the aesthetic appeal might suggest a decorative accent, the critical roles these eaves play in residents’ comfort, health and safety is unmistakable. With the Japanese summer bifurcated by near-constant rain followed by wilting, sultry heat, overhanging eaves not only protect walls from water damage, but allow residents to enjoy the extra ventilation of open rooms during heavy rains and sweltering summers.

The eaves found on traditional Japanese buildings, Buddhist temples and Shinto shrines employ an ingenious structural support system of blocks (masu) and brackets (hijiki) known as masugumi (Fig. 164). This began as a construction technique that arrived from the Asian continent with the introduction of Buddhistic architecture in the mid-sixth century, but over time came to be appreciated for its decorative appeal as “representative” Japanese. Though numerous variations on the masugumi style were developed over the years, the principal structure remains the same: projecting brackets to the front or sides, then placing blocks on those brackets at varying intervals, after which brackets are projected on them, and the process is repeated. The eaves are designed to extend beyond the walls to protect the house interior from rain, which is a certainty in Japan’s early summer rainy season. Many Japanese enjoy opening their windows during summer downpours for fresh air and the relaxing sights and sounds of the rain, while remaining safely beyond its reach.

Materials

Traditional Japanese house roofs were made of natural thatch grass (Fig. 165) or clay tiles (Fig. 166), depending on the building’s purpose, location and desired aesthetic. While both these materials feature the advantages of providing insulation and allowing water to evaporate, thatch grass is used in rural areas and mountainous regions due to its low cost and availability, whereas tiles are more prevalent in wealthier areas. Tile roofs typically consist of overlapping curved clay tiles, which provide extra stability and protection from rain, hail, and natural disasters like earthquakes.

Curves

Curved roofs (Fig. 167) are another signature feature of traditional Japanese architecture, such as temples and shrines, originally from a combination of superstition, functionality and aesthetics. The curved shape of the roof was believed to encourage good luck to flow in and bad luck to flow out, thereby warding off evil spirits and protecting the building. Functionally, the curved shape is designed to guide rain away from the house to prevent water from pooling as a countermeasure against water damage, mold and mildew. Finally, curved tiles and edge decorations—family crests, etc.—add to the aesthetic appeal of not only the roof, but the entire structure.

Jichinsai (“ceremony to quiet the earth”)

Jichinsai (Fig. 168) is a Shinto groundbreaking ceremony held prior to the construction of public and private buildings. Since construction “disturbs” the site and the neighborhood, this rite is a sign of respect to the local tutelary kami in order to secure its blessings for the project. The ceremony includes ritual requests for the building’s smooth completion, worker safety, and the health and prosperity of the new structure’s occupants.  

The ceremony is officiated by a Shinto priest on an auspicious day from the traditional lunisolar calendar. Despite jichinsai having lost much of its original meaning and sense of immediacy, breaking ground without it would still concern most Japanese today. Moreover, should the future occupants opt to forego the ceremony, the construction workers, who typically attend, can insist on having it performed for their own peace of mind.

On the day of the jichinsai, the priest sacralizes the site with upright bamboo poles connected by shimenawa rope festooned with shide, both sacred Shinto artifacts. In front of a makeshift Shinto altar (Fig. 169) with sacred sakaki branches and an array of other offerings, the priest recites a ritual invocation (norito) requesting the presence of the kami, then prepares the ground by sprinkling water, saké and salt over the site to purify the earth and dispel evil spirits.

In the ensuing “groundbreaking” phase, construction company executives bring out four traditional ritual wooden tools (Fig. 170) in sequence to symbolically level a small mound of earth that represents the act of breaking ground. Attendees receive a small serving of saké before the kami is released from the event. A protective amulet may be offered, then embedded in the building’s foundation. Once the ceremony is concluded, the future occupants visit the three houses on either side of the property to introduce themselves and present the families with small gifts. Jichinsai is primarily a Shinto rite, but there are Buddhist and Christian versions. Some homeowners and construction company CEOs also choose to conduct a “roof-raising” or “beam-raising” ceremony (jōtōshiki) before the building framework goes up, but this is less common in modern times.

Engawa (Japanese veranda)

The engawa (Fig. 171) is a porch-like strip of wooden flooring that typically surrounds Japanese homes, temples and shrines, and is enclosed by shōji and amado (“storm shutters”). That said, there are numerous types of, variations on, and exceptions to this general model. Some are open-air. Many are found on just one side of a structure. Nor do all engawa face outdoors; interior versions surround tsuboniwa, downsized garden courtyards inside the homes of wealthier families. The common denominator, however, is that engawa are platforms to view the many faces of nature. As such, this “zone of convergence,” of coming together, as it has been called, is one of traditional Japanese architecture’s “greatest hits.” It has been described as “among the most iconic and elegant features of Japanese homes” and “one of Japan’s most culturally significant architectural innovations.”

Wrap-around engawa often provide convenient alternative access to rooms on the periphery of the home’s interior. Structural support is provided by two rows of wooden posts resting on buried stones, one row running along the inner edge, the other row propping up the outer. The inner edge of the engawa and home interior can be completely partitioned with shōji, while amado on the outer edge protect both engawa and those inner rooms from the elements when necessary. Next, the area under the engawa slopes away from the home to promote drainage. Specifically, the angled surface extending outward to the roof’s perimeter line diverts excess water from the home’s foundation during Japan’s rainy season and other periods of high precipitation. This design defends against flooding and prevents standing water around the home.

Spiritual and Social Functions

The engawa is the most multifunctional, most informal, and most liminal space of a house. It is half inside, half outside, but considered part of the home. (Much like tatami, no shoes or slippers are allowed.) The engawa is an intermediary zone between Japan’s most important dichotomous worlds: first, man (mortals) versus nature (the gods), and second, public versus private social persona. Western architects describe the engawa differently, but based on what actually happens there, “interactive zone” sums it up best. That is, a space where man and nature, and where public and private persona come together, their differences deemphasized in deference to fundamental commonality. As “neither one nor the other,” the engawa symbolizes both the separation and continuity of these worlds. (Fig. 172)

In daily life, the engawa is a convenient, multifunctional venue ideally suited for short- or long-term activities, day and night, and by adults or children, either individually or in groups. It is a raised platform for enjoying the natural world, which is how the engawa is most commonly perceived by Japanese and foreigners alike, but is a favorite setting for other activities as well—a place where neighbors gather, where adults relax and children play. On warm summer days, families and friends often come out to chat, sip tea, enjoy box lunches, smoke cigarettes, read books, drink ori, or just lie back and gaze at the sky. The engawa often comes to mind when adults recall happy childhood memories. After the summer sun sets, there are parties for moon viewing and stargazing—yes, these are actual events in Japan—as well as summer fireworks displays, or impromptu gatherings as people make their way home from festivals. Moreover, housewives use engawa on a daily basis as a convenient place to hang laundry, air out futon, and finish up other household chores.

Nature viewing is typically a group activity, but for many a serious and meaningful individual pursuit. The Japanese go to great lengths to avoid feelings of loneliness in social contexts, but nature watchers report no such adverse feelings as they look out on tranquil gardens, ponds or groves of trees alone on their engawa. Just the opposite, in fact. To them, visual interaction with nature provides a reassuring sense of being a part of something greater that, in turn, replenishes their appreciation of life. Should an individual feel like socializing or want time alone with nature, the engawa extends an inclusive welcome.

Roofs and Engawa in Satsuma

Below are the twelve pictures that show my first-hand encounters with different roof and engawa types. Each of the first four show one of the roof categories discussed above, followed by a single house showcasing multiple styles in the same roof. This is common in Japan, especially in the case of larger houses. Next is a picture of the large eaves on my grandmother's house that provide protection from both the rain and sun, followed by the masugumi block support style of temple architecture under the gate of Hosshinji. And finally, for the roofs, there are two pictures showing the two main materials used in traditional Japanese roof construction: thatch and clay tiles. 

For the engawa, there are three pictures from my great-uncle's home, Bukkokuji Temple in Obama (located near Hosshinji) and the samurai house at Iriki Fumoto, respectively, illustrating the differences and similarities between residential and temple, old and new. 

Week 7: The Apprenticeship Begins

So, at long last… apprenticeship! It took two false-start, rain-day washouts, but on July 5th, we finally got down to business. My mentor, Mr. Tsuruzono, boasts a fifty-year career as a carpenter. He started out in Nagoya, Japan’s third largest city, in 1965 at the age of fifteen as an apprentice, earning his full credentials four years later. He went on to pursue his craft there for thirty years, working with and, eventually, leading crews of all sizes depending on the job. He and his wife relocated to Satsuma when he was fifty to live with her parents, and they have been here ever since.

He wasted no time putting me to work—taking down and disassembling shelves in the kitchen and hallway. From there, he sent me to the opposite end of the house, where the job was removing wall tiles and tearing up floorboards in what had once been a second, smaller kitchen (Figs. 185, 186). Stripping that room turned out to be my final assignment for the day, with Mr. Tsuruzono popping back in periodically to check on my progress.

The dismantling continued for two more days. Working together from day two, we opened a doorway, disassembled a tokonoma (Figs. 187, 188)—the raised alcove in the back wall of the main room—and removed tatami mats and shelves from the remaining rooms and hallways. The workday was eight to five, with an hour lunch break at noon. This was when I tried to draw him into conversation about Japanese carpentry in general, slipping in occasional questions about his career. He was surprisingly forthcoming and, as I soon discovered, a man of broad knowledge and strong convictions on carpentry-related issues.

On day one, he gave me a tutorial on why Japanese house sizes differ according to region. Not surprisingly, he began with Kagoshima homes, which are traditionally larger than those in Honshu and Hokkaido, the northernmost islands. The main reason is climate. As Japan’s southernmost prefecture, Kagoshima is also one of its hottest and most humid—regularly registering record high temperatures and 70%-100% humidity during the summer months. Larger houses help mitigate this muggy heat by creating a parallel increase in ventilation with the additional space. Next, he briefly mentioned physical necessity, pointing out that since Kagoshima is a major agricultural center, farming families require extra space to store harvests and house livestock. And finally, residences in the fumoto military strongholds discussed in Week 6 were also more spacious and better appointed, as they were built for high-ranking samurai warriors tasked with defending their respective homelands, and as such, entitled to special perks and a higher standard living than the farmer, artisan and merchant classes.

At the same time, Mr. Tsuruzono expressed sadness at some of the directions Japan was headed in. One was its graying society, which was becoming a serious obstacle to tree proliferation due to the elderly population’s declining ability to sustain it. Residents in rural areas have traditionally maintained their own copse of sugi and other trees which, since they take decades to reach maturity, have been passed down from generation to generation. However, with Japan’s shrinking birthrate and the exodus of even those diminishing numbers of young men and women to urban areas, the remaining middle-aged and senior citizens able to properly care for these trees is plummeting. What’s more, much of Japan’s best wood is exported to world markets to meet the growing demand for high-quality timber. Although sugi trees remain plentiful in natural forests, the alarming truth is that soon there might not be enough able bodies to properly support this vital resource.

On the third day, the talk turned to traditional Japanese carpenters and how their role is being diminished in today’s more modern, secular society. Japanese carpenters were once known as jack-of-all-trades in construction, having mastered skills from drafting house plans to hammering last nails. However, with jobs segregated to individual tasks for greater economy and time efficiency, as well as the growing demand for modular construction, in which house segments are prefabricated in factories for assembly on site, carpenters have lost much of their standing in the industry. Mr. Tsuruzono is “officially” retired, but still receives frequent requests—such as our current renovation—from Satsuma residents as the only carpenter in the area.

The owners of the empty house several doors down from my grandmother’s hired crews to tear down and rebuild the structure in a fashion similar to American construction—stick framing, insulation and multiple people on the retrofit—but few in the area have the means to afford such an undertaking. Once Mr. Tsuruzono quits for good, less fortunate homeowners will be left to face another struggle that has come to represent a sign of the times.

Between the physical restoration work on my great-uncle’s house and my talks with Mr. Tsuruzono on Japanese architecture and carpentry, I am getting an invaluable first-hand perspective on the changes in Japanese homes and carpentry to date. There were some surprises as well, including similarities to western carpentry. For instance, although metal fasteners are supposedly strictly taboo in Japanese architecture, that apparently applies only to the structural pillars—and sometimes not even them. Many houses, even my grandmother’s, have small, decorative kugi-kakushi (nail concealers) (Fig. 189) covering joints fastened with metal nails, instead of wooden blocks crafted as joint locking fixtures. It has been only three days with Mr. Tsuruzono, and already I have learned many things that would have proven difficult to impossible to get with Google and YouTube. I look forward to sharing more takeaways from this apprenticeship with readers. Though frustrating at first, it was well worth the wait.

Finally, a “programming” reminder: Next week is the road trip to Kirishima, home of ryokan (Japanese inns) and onsen (hot springs) to kill for. And that’s just the fun stuff! The “work” agenda includes the previously noted Kareigawa Station and Kirishima Shrine, a shrine known nationwide for its amazing atmosphere and architecture. I have a feeling Week 8 may be one of the most exciting yet, so stay tuned. I don’t think you’ll want to miss it. Hope to see you then!