When the samurai warriors of the Kamakura era (1185— 1333) assumed power, they did not immediately disown the architectural styles of the Heian nobles, but merely added (or, in some cases, removed) features in response to their martial needs and their new Zen outlook. As the country was at war, there was no logic in detached rooms and open galleries, and the samurai immediately tightened up the design, putting the entire house under one roof. They eliminated the pond and added a surrounding board fence for protection, even as interior curtains and hinged doors were replaced by sliding doors of paper over a wooden frame. And as rooms became more clearly identified, they were defined in terms of function. The early influence of Zen was seen most noticeably in the gradual disappearance of the ornamental aspects of shinden design as the samurai came to prize austerity and frugality.
During the Ashikaga era (1333-1573) which followed, when Zen monks assumed the role of advisers and scribes for the illiterate military rulers, a special writing desk, called a shoin,
appeared in the houses of the more influential samurai. The shoin was a window alcove with a raised sill, which overlooked a private garden and was used by the monks for reading and writing. Next to this was a chigai-dana, a wall cabinet recessed in a niche and used for storing papers and writing, utensils. (These new domestic appointments had been lifted by the Zen monks directly from the chief abbot's study in Chinese Ch'an monasteries.) The shoin study room immediately became a focus of fashion among the samurai, even those who could neither read nor write, and before long it was the finest room in a house. Guests began to be received there and another feature from Zen monasteries was added: the art-display alcove, or tokonoma. (In Chinese Ch'an monasteries the tokonoma was a special shrine before which monks burned incense, drank ceremonial tea, and contemplated religious artwork. That such a shrine should appear in a reception room of a social-climbing samurai's house is vivid testimony to the pervasive influence of the Zen monk advisers.) The samurai also added an entry vestibule called a genkan, still another feature drawn from Zen temples. As a result of all these additions and modifications, shinden architecture was completely transformed into a functional samurai house whose style became known as shoin. Forgotten were the Chinese tile roofs and vermilion paint; thatch and unfinished woods reappeared. Paradoxically, the supplanting of shinden design by shoin was in many ways merely the ousting of a T'ang Chinese style by a Sung Chinese style. However, the T'ang architecture had been that of the Chinese court, whereas the Sung was drawn from Ch'an monasteries and coincidentally contained many of the aesthetic ideals of the earlier native Japanese dwellings and shrines.
By the waning years of the Ashikaga era, the shoin design had influenced virtually every aspect of Japanese architecture, bringing into being almost all the qualities of what is now thought of as the traditional Japanese house. The movable floor mats were replaced by wall-to-wall tatami, woven straw mats bound with a dark fabric band at either end and standardized to a size of approximately three by six feet. Soon rooms were being defined in terms of the number of tatami required for the floor—and modular architecture had been invented. Sliding, but removable paper partitions called fusuma became the standard room dividers, and the tokonoma became less a religious shrine than a secular display case where vertical monochrome scrolls and flower arrangements were put on view. Oddly enough, one of the few Chinese innovations the Japanese persistently chose to ignore was the chair. As a result, a Japanese residence has always maintained an entry vestibule where footwear is removed, something unnecessary for the Chinese, who had no reason to consider the floor a couch and could keep their shoes on. One important side effect of this choice is that eye level in the Japanese room—that is, the level from which the room, its art, and its appointments are viewed—has remained significantly lower than in houses with furniture, a characteristic that influences the placement of art as well as the layout of the accompanying garden.
The culminating style of Japanese architecture was the sukiya house, essentially a free-hand rendering of the formal samurai shoin. The sukiya style reflected a number of aesthetic and architectural ideas embodied in the Zen-inspired Japanese teahouse, and it allowed for considerable experimentation with materials and design. Less powerful and more delicate than the shoin, it was in many ways the ultimate extension of Zen austerity, even to the point where walls were often left unplastered. The shoin had been the house of warriors; the sukiya was a style for the common man and as such has contributed significantly to the overall tradition of Japanese architecture. Shoin and sukiya houses, heirs to the legacy of Zen monks and later Zen aesthetes, are the reference point for what is now understood to be the traditional Japanese dwelling.
The deceptively fragile appearance of the house makes it appear at first an impractical invention for a land faced with recurrent earthquakes. Yet its lightness and flexibility, like those of a judo expert, actually contribute to its safety. Part of the reason is its foundation, which "floats" with the earth rather than being anchored rigidly. The traditional house is not held up by walls but by stout columns, almost a half-foot in diameter, embedded at their base in niches sunk into large, individually placed stones which are only partially buried. These columns reach through the house to the ceiling, whose weight secures them in their precarious foundation. In ordinary houses, the roof is a steeply sloping, four-sided pyramid whose light underframe is covered with multiple layers of shingles made from the tough bark of the hinoki tree.
A second set of shorter posts, similarly supported bv partially buried stones, holds up the platform that is the floor, a wooden deck of closely fitted planks set about two feet above the earth. The outer perimeter of the flooring becomes a veranda or walkway, called the engawa, and the inner space is partitioned into rooms by light walls of paper, plaster, and wooden grillwork. The outer walls of the house, which serve no structural purpose, are sliding latticework panels called shoji, which are covered with translucent white rice paper, bathing the exterior rooms in a soft daytime light. The shoji, ordinarily installed in pairs approximately six feet high and three feet wide, unite rather than divide the interior and exterior; during the summer they slide open to provide fresh air and direct communication with the outdoors. If greater insulation or safety is required, a second set of sliding panels, or amado, similar in appearance to Western doors, may be installed outside the shoji. Between columns too narrow to accommodate a pair of shoji there may be a solid wall consisting of a two-inch-thick layer of clay pressed into a bamboo and rice-straw framework and finished inside and out with a thin veneer of smooth white plaster. Similar walls may be built inside the house where appropriate, and they and the columns are the house's only solid surfaces. The dull white color and silken texture of the plaster walls contrast pleasantly with the exposed natural grain of the supporting columns.
Interior rooms are separated by partitions consisting of light wooden frames covered in heavy opaque paper, often decorated with unobtrusive designs. These paper walls, called fusuma, are suspended from tracks attached to overhead crossbeams. They slide to form instant doorways, or when removed entirely, convert two smaller rooms into one large apartment. Fusuma provide little privacy between rooms except a visual screen, and it is rumored that this undesired communication increasingly inhibits lovemaking by modern parents.
The overhead crossbeams, installed between the columns at a height of slightly over six feet, are similar to the columns in diameter and appearance. The ceiling of the rooms is roughly two feet above the crossbeams, or kamoi, with the intervening space usually filled either by a vertical open wooden latticework, the ramma, or a plaster-and-board combination, the nageshi. On exterior walls of the ramma is ordinarily a solid extension of the shoji which inhibits air flow from the outside. The kamoi, nageshi, and ramma have a structural as well as aesthetic obligation; they are the only solid lateral supports between the upright columns. The ceiling itself is a light wood latticework over which has been laid a platform of thin boards still in their natural state, as is all the woodwork.
Visitors enter through the genkan portico, where street shoes are replaced by soft-soled slippers, to prevent scratches on the exposed wooden veranda and hallways. At the entrance to a tatami-carpeted room, the slippers too are relinquished, and host and guests are both in stocking feet, a state that encourages familiarity. The reception room is empty as a cell, and as it basks in the diffuse light of the shoji, it seems suspended in time—heedless of the season. The only furniture may be a small central table around which guests and host seat themselves on square cushions. Or perhaps there are lamps with rice-paper shades, one or two knee-high chests of drawers, and if the weather requires it, one or more charcoal braziers, either a small moveable hibachi for hand warming or a larger heater sunk into a center recess in the flooring, often beneath the table, or both. The purpose of these is apparently more symbolic than functional, for they do little to influence the temperature in the paper-walled rooms. Arrangements for summer cooling are equally metaphysical; the shoji are simply thrown open in hopes of snaring wayward breezes, whose meager cooling is enhanced psychologically by the tinkle of wind bells hung in the verandas.