Saturday, December 11, 2010

Wooden houses near the beach of the Dorey bay

While I was traveling to Numfor island with a ferry boat, from the sea, I saw rows of wooden houses constructed along the beach up to a slope in the Dorey bay of Manokwari city. These type of wood construction is common in this region because wood is more durable in withstanding strong earthquake. Wooden houses of the Papuan tribes in coastal region are different from the ones that I usually see in the mountainous region of West Papua. Houses that are built near the sea often have pillars that stand from the bottom of the beach to two meters above the sea surface to allow for space for high tide. The wood that are used for the house pillars have been chosen from the species that will not easily rot when soaked in the salty water for longer time.
In recent years, some Minahasan people from Woloan village migrated to Papua and introduced prefabricated wooden houses that can be dismantled from the place where it was first constructed and displayed and reassembled in a new place for the new owner of the house. Although timber as the construction material of the house is abundant in this city, the Minahasan type of the wooden houses cannot easily penetrate the local market that has already had its own indigenous model which is Rumah Kaki Seribu or "a thousand leg house" which is the typical wooden house from Arfak mountains
The wooden houses made by carpenters from Woloan who have now lived in Manokwari are more modern and fine in their fabrication. The carpenters use modern machine to make blocks and panels of wood that will form the house.
The big earthquake that hit Manokwari city in 2008 had reminded the city dwellers that having houses with wooden frames is more safe that building houses only with concrete materials. I personally believe that wooden houses whether they are traditional or modern in design will always be attractive in Papua because of the frequent earthquakes that hit the island.
Corrugated Metal Roof for Wooden House Construction
Most of the wooden houses in West Papua are now using corrugated metal roof called "seng" or zinc (Zn) This type of roof is very popular not only in West Papua but also in Indonesian and even all over the world. In the past, Papuan people usually use sago palm leaves as the roof cover for their houses. These leaves can only be used for 2 years. They have to be replaced  Although the corrugated metal roof is called zinc, actually it is made of layers of iron, aluminum and zinc. The zinc metal roof has a range of thicknesses from 0.2 to 3.8 milimeters. There are some possible combination that we can find in corrugated metal roof that we usually find in the housing materials shop in Indonesia:
Fe coated by seng = 1.50%
Pb coated with seng = 0.90%
Al coated with seng = 97,25%
Zn coated with seng = 97.25%
I got the chemical compositions of the corrugated metal roof from this website: http://www.adimas.co.id/ind/senggalvanis.htm
Another material that is now getting more attention from home builders is Zincalume G-550. It is alloyed steel plate protected with metal layers whose composition is 55% aluminum and 45% seng. This is Zincalume layer is twice up to six times more resistant to corrosion that other galvanic steel plate for similar application as roof deck. When there is a fire in a wooden house, the chemical composition of the metal roof plates change significantly due to overheating. As a result they cannot be used for rebuilding the house anymore.
Tens of years ago, the roofs of the wooden houses in Indonesia were from palm leaves. These materials had to be replaced every two years. In addition, they were not fully watertight. With the improvement in the home building technology in Indonesia and the availability of more durable materials, now most of the wooden houses have been protected by corrugated metal roofs that can withstand rain and sunlight for tens of years. by Charles Roring
Also read: