Omo sebua
Encyclopedia
Nias
Nīas is an island off the western coast of Sumatra, Indonesia. Nias is also the name of the archipelago, containing the Hinako archipelago....
island, Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
. They are built only for the houses of village's chiefs. Situated in the centre of a village, omo sebua are built on massive ironwood
Ironwood
Ironwood is a common name for a large number of woods that have a reputation for hardness. Usage of the name may include the tree that yields this wood...
piles
Deep foundation
A deep foundation is a type of foundation distinguished from shallow foundations by the depth they are embedded into the ground. There are many reasons a geotechnical engineer would recommend a deep foundation over a shallow foundation, but some of the common reasons are very large design loads, a...
and have towering roofs. Nias culture, with former frequent inter-village warfare, has made the design of omo sebua impregnable to attack. The houses' sole access is through a narrow staircase with a small trap door above. The steeply pitched roofs can reach 16 metres (50 feet) in height. Apart from a strong defense against enemies, omo sebua have proven earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
resistance.
Background
Sibolga
Sibolga is a city and a port on the west coast of North Sumatra province, in Indonesia. It is located on the western side of North Sumatra, facing the Indian Ocean and is a transit harbour to Nias island. It was hard hit during the 2004 Indian Ocean Earthquake.- History :Poncan Ketek Island in...
at the western coast of Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
, separated by the Mentawai Strait
Mentawai Strait
Mentawai Strait separates Sumatra and Mentawai Islands, Indonesia....
. Nias is part of the North Sumatra
North Sumatra
North Sumatra is a province of Indonesia on the Sumatra island. Its capital is Medan. It is the most populous Indonesian province outside of Java. It is slightly larger than Sri Lanka in area.- Geography and population :...
province with Gunungsitoli as its administrative center. The island covers an area of 4,771 km²; the largest of its 131 chain of islands parallel to the Sumatran coast. The population of the island is 639,675 people including Malay, Batak
Batak (Indonesia)
Batak is a collective term used to identify a number of ethnic groups predominantly found in North Sumatra, Indonesia. The term is used to include the Toba, Karo, Pakpak, Simalungun, Angkola and Mandailing, each of which are distinct but related groups with distinct, albeit related, languages and...
, Chinese
Overseas Chinese
Overseas Chinese are people of Chinese birth or descent who live outside the Greater China Area . People of partial Chinese ancestry living outside the Greater China Area may also consider themselves Overseas Chinese....
) and the indigenous inhabitants Ono Niha.
Once a megalithic head-hunting society, its economy was based on agriculture and pig-rearing, and was supplemented by export of captured slaves in inter-village warfare. Although its isolation has contributed to the uniqueness of its culture, the Nias Island chain has been trading with other cultures, other islands, and even mainland Asia since prehistoric time. The predominant religion is Protestant Christianity
Protestantism
Protestantism is one of the three major groupings within Christianity. It is a movement that began in Germany in the early 16th century as a reaction against medieval Roman Catholic doctrines and practices, especially in regards to salvation, justification, and ecclesiology.The doctrines of the...
with over than 75% of the population; the remaining are about evenly divided Muslim
Muslim
A Muslim, also spelled Moslem, is an adherent of Islam, a monotheistic, Abrahamic religion based on the Quran, which Muslims consider the verbatim word of God as revealed to prophet Muhammad. "Muslim" is the Arabic term for "submitter" .Muslims believe that God is one and incomparable...
(mostly immigrants from elsewhere in Indonesia) and Catholic
Roman Catholic Church
The Catholic Church, also known as the Roman Catholic Church, is the world's largest Christian church, with over a billion members. Led by the Pope, it defines its mission as spreading the gospel of Jesus Christ, administering the sacraments and exercising charity...
. However adherence to either Christian or Muslim religions is still largely nominal; Nias continues to celebrate its own indigenous culture and traditions as the primary form of spiritual expression.
Niassan society is highly stratified and chiefs, particularly in the south of island, had access to a wealth of material resources and human labor. It was with this wealth that the early twentieth century saw the chiefs of the isolated island build themselves the grand omo sebua.
Villages
Villages in the island's south are laid out either in a single long cobblestoneCobblestone
Cobblestones are stones that were frequently used in the pavement of early streets. "Cobblestone" is derived from the very old English word "cob", which had a wide range of meanings, one of which was "rounded lump" with overtones of large size...
street or to a cruciform
Cruciform
Cruciform means having the shape of a cross or Christian cross.- Cruciform architectural plan :This is a common description of Christian churches. In Early Christian, Byzantine and other Eastern Orthodox forms of church architecture this is more likely to mean a tetraconch plan, a Greek cross,...
plan with the chief's house at one overlooking the street. They can be large with up to 5,000 residents. Villages were built with defence in mind, strategically sited on high ground and are reached by steep stone stairways and are surrounded by stone walls. Smaller villages, however, would not have been defendable in former slave-trading days. In contrast with houses of northern Nias, which are free-standing, oval in shape and built on piles, southern Nias houses are built in terrace
Terraced house
In architecture and city planning, a terrace house, terrace, row house, linked house or townhouse is a style of medium-density housing that originated in Great Britain in the late 17th century, where a row of identical or mirror-image houses share side walls...
s forming long rows.
Buildings
Omo sebua, or chief's houses, are situated in the centre of the village and are built on massive ironwood pileDeep foundation
A deep foundation is a type of foundation distinguished from shallow foundations by the depth they are embedded into the ground. There are many reasons a geotechnical engineer would recommend a deep foundation over a shallow foundation, but some of the common reasons are very large design loads, a...
s and have towering roofs. The piles rest on large stone slab
Slab
-Physical materials:* Slab , a length of metal* Concrete slab, a flat plate used in construction* A piece of stone or concrete used to pave sidewalks or road surfaces* Slab : That portion of a tectonic plate that is subducting...
s and diagonal beam
Beam (structure)
A beam is a horizontal structural element that is capable of withstanding load primarily by resisting bending. The bending force induced into the material of the beam as a result of the external loads, own weight, span and external reactions to these loads is called a bending moment.- Overview...
s of the similar dimension and material providing longitudinal and lateral bracing, enhancing flexibility and stability in earthquakes. The warring culture built them to intimidate with size and the houses are virtually impregnable to attack with only a small trap door above a narrow staircase for access. The steeply pitched roofs reach heights of 16 metres (50 feet); gable
Gable
A gable is the generally triangular portion of a wall between the edges of a sloping roof. The shape of the gable and how it is detailed depends on the structural system being used and aesthetic concerns. Thus the type of roof enclosing the volume dictates the shape of the gable...
s project dramatically at both the front and rear, providing both shade and shelter from tropical rains, and giving the building a hooded, towering appearance. With structural members slotted together rather than nailed or bound, the structures have a proven earthquake resistance.
Like the omo sebua, commoners' homes are rectangular in plan. As a defensive measure, interconnecting doors link each house, allowing villagers to walk the full length of the terrace without setting foot on the street below. Both the commoners' houses and the aristocracy's omo sebua have bowed galleries underneath the large overhanging eaves. Presumed to have been inspired by the bulbous stern
Stern
The stern is the rear or aft-most part of a ship or boat, technically defined as the area built up over the sternpost, extending upwards from the counter rail to the taffrail. The stern lies opposite of the bow, the foremost part of a ship. Originally, the term only referred to the aft port section...
s of Dutch Galleon
Galleon
A galleon was a large, multi-decked sailing ship used primarily by European states from the 16th to 18th centuries. Whether used for war or commerce, they were generally armed with the demi-culverin type of cannon.-Etymology:...
s, they provided a defensive vantage point, and in times of peace, a ventilated and comfortable place from which to observe the street below.
The interiors are built from planed
Plane (tool)
A hand plane is a tool for shaping wood. When powered by electricity, the tool may be called a planer. Planes are used to flatten, reduce the thickness of, and impart a smooth surface to a rough piece of lumber or timber. Planing is used to produce horizontal, vertical, or inclined flat surfaces on...
and polished hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
boards - often ebony
Ebony
Ebony is a dense black wood, most commonly yielded by several species in the genus Diospyros, but ebony may also refer to other heavy, black woods from unrelated species. Ebony is dense enough to sink in water. Its fine texture, and very smooth finish when polished, make it valuable as an...
- that are slotted into each other using tongue and groove
Tongue and groove
A strong joint, the tongue and groove joint is widely used for re-entrant angles. The effect of wood shrinkage is concealed when the joint is beaded or otherwise moulded...
joinery. The internal timbers often feature bas-relief carvings of ancestors, jewelry, animals, fish and boats with a balance of male and female elements that is essential for Niassan concepts of cosmic harmony. The more opulent houses are further decorated with freestanding wooden carvings and the internally exposed rafter
Rafter
A rafter is one of a series of sloped structural members , that extend from the ridge or hip to the downslope perimeter or eave, designed to support the roof deck and its associated loads.-Design:...
s are adorned with jaw bones from pigs that were sacrificed for the workers' feast at the time of the houses' completion.
2005 Earthquake damage
The December 2004 Indian Ocean earthquake and tsunami caused (only) coastal damage to Nias, but the March 2005 Nias earthquake2005 Sumatra earthquake
The 2005 Sumatra earthquake, referred to as the Nias Earthquake by the scientific community, was a major earthquake on 28 March 2005, located off the west coast of northern Sumatra, Indonesia. Approximately 1300 people were killed by the earthquake, mostly on the island of Nias...
had a devastating effect on the island. More than 80% of modern public buildings were destroyed. Traditional homes were more earthquake-resistant and most survived.
Reconstruction efforts were hampered by the death of many traditional craftsmen, and the fact that NGOs lacked knowledge of Niasian building methods. The cost of repairing damaged traditional homes was estimated to be similar to building new ones, because collapsing support pillars meant that the house had to be dismantled and reconstructed.
NGO house designs were typically smaller than traditional ones, and lacked many elements that were fundamental to Nias' culture.