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Building Materials and Construction Techniques

The structure of Balinese buildings parallels the local tri angga classification system, which assumes that everything in the natural world can be divided into the three components of nista, madya, and utama (p. 4). These categories are hierarchically ordered in terms of a set of spatial coordinates (high, middle, and low) identified with the base (nista), the house posts and curtain walls (madya), and the roof (utama).

Movement to the Right

The first post to be erected should be the one that stands at the kaja-kangin corner of the building, the most auspicious position in terms of the Balinese compass rose. An offering platform is attached near the top of this post, and the erection of the rest of the posts is determined by the law of “movement to the right,” an idea found all over Indonesia. In the case of Bali, this means in a clockwise direction.

The Base

The base, or stereobate, typically consists of four low walls of brick or stone, infilled with stamped earth. In unimportant or humble buildings, this packed earth surface will also form the material for the floor, but where finances allow, it will be paved. Similarly, the walls of the base may be plain, profiled, or carved with reliefs depending on the nature of the building and the status and wealth of the owner.

The Timber Frame

The main load-bearing elements of the building consist of a timber post-and-beam framework. This structure supports the hipped roof, which is formed from a coconut wood and bamboo frame covered with grass thatch (alang-alang) or, in more affluent households, with clay tiles.

The height of the posts (adegan) is determined by measurements taken from the house owner’s body, and the dimensions of the house posts, in turn, determine the proportions of the building. The standard unit of measurement for house posts is a rahi, the length of a line drawn between the end of the lifeline at the base of the thumb and the tip of the index finger. Optimal heights are 20, 21, or 22 rahi.

A measurement of 19 rahi is expressly avoided, the explanation being that it would expose the occupants of the house to disease, crime, and other misfortunes. The latter measurement is sometimes referred to as buta dengan milara and is said to be the cause of unhappy love affairs.

The posts of the house rest on masonry or stone column bases called umpak, and the rigidity of the structure is established by tie-beams which are stiffened at the joints by shores or brackets. Individual components are joined by mortise-and-tenon, or lap joints, and are secured by a wedge or wooden peg.

The Asta Kosali prescribes what kinds of timber should be used for particular building requirements. Traditionally, the preferred material for house posts is teak, which ideally should be cut from a living tree growing locally, although teak imported from Kalimantan or Java is considered to be superior.

Offerings must be made before the tree is felled and, when the posts are ready to be raised into position, care must be taken to ensure that they are erected according to the direction of growth of the tree trunk from which they were cut, with the root end being placed in the foundations and the growing tip end supporting the roof. On no account may posts be erected “upside down,” that is to say, with the direction of growth inverted.

The Walls

The walls of Balinese houses are made from stone, brick, or even simply mud. They do not carry any load, as they are completely detached from the timber structure that supports the roof.

The favored building material is paras, a kind of soft sandstone that is cut into uniform brick-sized blocks and then gently baked in the sun. Using muddy water for mortar, these bricks are rubbed back and forth on the preceding course until they stick. When the mud is still wet, it provides an element of adhesion. Subsequently, the wall is held together simply by its weight and the near-perfect fit between courses. Paras is a very plastic material, which can be easily carved, but is not very durable and soon deteriorates when exposed to the elements, hence the ancient appearance of many Balinese buildings, despite the fact that most structures are no more than a few years old.

The Balinese also employ adobe as a building material. This is made locally from wet earth kneaded into balls and placed in the sun to dry.

Walls are constructed by placing these mud balls in parallel rows and then filling the crevices with more mud. Another layer is added on top, and the process is repeated until the desired wall elevation is achieved.

Adobe is even less durable than paras. As such, it always has a protective coping of thatch that is usually made from rice straw. Rice straw thatch does not itself last very long and is usually renewed after each harvest.

The Roof

Since the materials used to make walls are not very durable, care is taken to ensure that the walls are well protected from the elements by widely overhanging eaves. The main framework is made of bamboo with the roof ridge supported by king posts, girders, and columns.

The usual roofing material used in ordinary buildings is a thick thatch that is made from alang-alang grass (Imperata cylindrica). The grass is gathered in bundles which are then doubled over the midrib of coconut fronds and stitched in place. These sections of thatching are lashed on to the bamboo framework of the roof using red-dyed rattan cords or ties made from the natural fiber of the sugar palm (Arenga pin-nata). Extra thatch is placed along the ridges for reinforcement.

Lastly, the roof is combed with a special type of rake and the bottom edge is trimmed with a knife. Such a roof, which may be up to 50 centimeters in thickness, can last for many years.

More important structures may employ locally made clay pantiles, or even modern Marseilles tiles, while split bamboo shingles are a popular choice for roofing material in mountain regions as they are more durable than thatch. In the case of religious structures and family shrines, black thatch (ijuk) from the sugar palm is used for roofing instead of alang- alang.

Traditional Balinese houses are built almost entirely of organic materials: wood, bamboo, grass thatch, and plant fibers

A pegged mortise-and-tenon joint.

The method of tying alang-alang thatch.

The parts of a house post.