3.Technology

	- a.Harmony, which shows that the esthetic values of Torajan society are reflected in ornaments and decorations.
	- b.Goodness of form, which shows beauty through physical form and constructed exteriors.
	- a.Repetition, pattern, and harmony; the balance between the ornaments of Rumah Tongkonan shows the cultural identity of local society.
	- b.Balance, which shows that the beliefs of local society remain strong.
	- c.Ground, which shows a particular indigenous identity through the use of a stilt-based construction.
	- d.Sharpness and imbalance, which show the core identity of Torajan society through the roofs that resemble ships, thereby connoting the ancestors. The roofs of Rumah Tongkonan are larger than the bodies and foundations, highlighting their protective role.

The Torajan people have sought to conserve nature by avoiding encroaching on virgin forests. Land usage is also efficient. At the base, the area between the floor and the ground is used for keeping animals. The use of stilts also minimizes the amount of land that must be excavated. The majority of Torajans earn a living through horticulture and husbandry. Most use their land for traditional agriculture with minimal environmental impact.

1.**Efficiency in material usage.** Efficiency is evident in the building materials selected for Rumah Tongkonan. Almost all materials are taken from nature, including the base, ceiling, roof, floors, windows, and doors. Many of the materials are unique to South Sulawesi, yet abundant and easy to access. Such renewable organic materials ensure that sustainability is maintained. These materials are also well suited to the local climate and its specific geographic conditions.

*Understanding Local Architectural Forms as a Sustainable Design Transformation DOI: http://dx.doi.org/10.5772/intechopen.109560*


Rumah Tongkonan uses a sustainable design that is well suited to local conditions. Although these dwellings are part of Torajan custom, their design is a complex one that reflects local wisdom, custom, technology, identity, lifestyles, and esthetic values. It is these elements that have enabled Rumah Tongkonan to survive into the present day and may be applied in contemporary architecture.

Every component of Nusantara Architecture has unique characteristics, which are influenced by the natural and geographic conditions wherein it is situated. Systems, materials, and structures vary throughout the archipelago. Many architectural works use local materials, including woods that are unique to their regions and are thus sustainable. Their designs make maximal usage of wind and the sun for ventilation and lighting; together with the usage of local materials, this ensures that their environmental effects are minimized. Such structures are uniquely suited to surviving natural disasters and enduring the ravages of time.

#### **4.5 Dwellings in Kampung Naga, West Java, Indonesia**

Kampung Naga is a customary Sundanese settlement in Neglasari Village, Salawu District, Tasikmalaya Regency, West Java. It consists of forests, a river, rice fields, and the settlement proper. All of these have fixed boundaries [18].

Customary law requires dwellings to use the same form, color, and materials as their ancestors, as this mitigates social gaps between residents (see **Figure 7**). Per the community's ancestral knowledge, it is forbidden to build homes with concrete walls and tiled roofs, even when financially viable. Customary homes are built communally. Dwellings are built on stilts, ensuring proper ventilation and air quality. Most materials are collected from the surrounding area. Nonetheless, some elements may use prefabricated materials. Kampung Naga consists of a series of stilted longhouses. Air flows from the verandas to the rear of the home, with the form serving to draw air backward and promote circulation.

Most dwellings in Kampung Naga are made of light and environmentally friendly natural materials, aside from nails, glass, and chalk. Nature is the main source of materials for the community, which relies heavily on stones and local vegetation. Dwellings in Kampung Naga are built upon a foundation of natural stone, measuring 40x40x40 cm. These foundations are pedestals, reaching approximately ±50 cm above ground level. Due to this foundation, the dwellings in Kampung Naga are free of termites. At the same time, this foundation ensures stability in the area's mountainous terrain (**Figure 8**).

**Figure 7.** *View of Kampung Naga.*

#### **Figure 8.**

*Customary homes are built communally (Source: translate from UPI).*

*Understanding Local Architectural Forms as a Sustainable Design Transformation DOI: http://dx.doi.org/10.5772/intechopen.109560*

**Figure 9.** *Customary homes are built communally (Source: UPI).*

Dwellings in Kampung Naga are walled with *gedhek* (woven bamboo), albasia wood, or jaro (sturdy wooden shafts, bound together with bamboo). Walls may be left bare or covered in chalk, which serves to insulate the room and protect the walls from termites. Along the walls, about 23 cm above the floor are wooden bars that are 20 cm in width. These bars serve to prevent the walls from collapsing and chalk from peeling. Such materials are highly flammable; as such, the door frames and kitchen walls are made of sasag. Dwellings are made of albasia/sengon wood. The ceilings consist of two layers. The lower layer is made of palm leaves, while the upper layer consists of palm fibers that are held together with bamboo reeds. These ceilings have several panes of glass to allow light to enter the home. The roof takes the form of a Julang Ngapak, which spreads to both sides akin to a bird's wings (**Figure 9**).

Kampung Naga community in building houses contains local wisdom values that have been proven to be very effective in disaster mitigation, starting from the production and selection of building materials, preparation of structures, and building foundations resistant from earthquakes.
