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Date & Time in Bali

CURRENT LOCAL DATE AND TIME IN BALI:

Thursday, 14th November 2024
3:44:19 am

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Wood damaging pests and wood decay

These plagues are catogorized under insect attacks (termites, borers (wood eating beetles) and fungus. Wood attacking insects are the carpenter ants and the termites, the latter the most notorious and most damaging. Borers (beetles) can be split into old wood borers and fresh wood borers (powder post beetles, larder beetles). Some types of Fungi can be damaging, provided the heartwood is susceptible.  

TERMITES

There are about 2,600 species of termites, whereas the most notorious are the carpenter ants and the Formosa termites, the latter most dangerous and damaging.
Most termites (*) attack from natural grade. Only the drywood termite is able to nest in ceilings and roofs. Flying termites are visible when their colony swarms which are provoked by heavy rainfall and warm, humid temperatures among other triggers. Swarms occur when established colonies produce winged male and female termites in order to reproduce. After these mating flights, fertilized termites shed their wings and go on to establish new colonies underground. However, termites seen flying in a home are indicative of a mature colony which may sooner or later attack the wooden parts of your house from ground floor to natural grade. If unnoticed they may creep up into your roof and roof trusses.

(*) The common name "white ants" is a very poor choice, since termites are not ants and have been shown to be more closley related to cockroaches 

For a very detailed review about termites go to the < special termite page >

Winged-termite

Winged termites


Termites and hardwood

Termites cause billions of dollars in damage each year in the world. They primarily feed on wood, but also damage paper, books, insulation, and even swimming pool liners and filtration systems.

There are only a few wood species available in the world which are 100% guaranteed termite resistant. These wood species can only be found in Africa and South America, but definitely NOT in Indonesia, however, there are a few Indonesian hardwood wood species which will give some protection when the proper part of the tree is used (the core or "heart").
Termites eat the cellulose from the wood cells. The harder these cells the less interested they are in their dinner. Any tree has a core called heartwood. This is the hardest part of a tree. There is only one wood species in Indonesia which have a core so dense and hard that termites can't eat it. This species is Bangkirai. Close followers are Bojonegoro Teak, Merbau and Iron wood.

 Timber-trunk

However, as is the case with all trees the outer rings (called sap wood) are soft or softer than the core (heartwood). As a result termites do not attack Bangkirai heartwood and in a lesser extend the heartwood from the other species mentioned, however, the termites attack the juicier and softer sapwood. The solution would be that we only buy heartwood from our suppliers, however, so unfortunate, this is merely a mission impossible, since the suppliers do not want to be left with only a stock of sap wood.  

As such the suppliers mix the wood in portions of heartwood and sapwood, or will ask a 30% higher price for heartwood only. In conclusion we cannot guarantee that all the wood that we use is not susceptible to termite attacks whether it is Bangkirai, Teak, Merbau or Iron wood.

HOWEVER,....................

That was the bad news. There is also good news. When the mixed wood of one of the above mentioned wood species is used in combination with our speciallin-house developed treatmemt, a termimesh system or a termite barrier you will be much safer for many, many years to come, whereas a combination with Bangkirai heartwood for the lower parts of the unit (from natural grade up to and including the ground floor) is the best option. For those who have the budget available we offer the grandeur solution (see bottom of this page "STOP PRESS" marked in orange).

Termite-mudding-1

 Termite-mudding-2

Termite mudding. If you see this: you have termites !!!!!!

Fact

Most Indonesian wooden prefab house manufacturers state on their web sites that Bangkirai and Merbau are documented to absolutely termite resistant. We are of the believe that these companies should do their home work again and shall carefully read what is written in the following laboratory reports:  
J. Kenneth Crave and Carrie H.M. Tome from the University of Hawaii evaluated the resistance of Indonesian Bangkirai to the attack of the  dangerous Formosa termite. Their investigation revealed that "as with all durable tree species only the heartwood and not the sapwood of these species is reputed to be durable". See page 504 line 15 of their report which can be downloaded via https://www.ctahr.hawaii.edu/gracek/pdfs/212.pdf  This report supports our claim that the only Indonesian fully termite resistant Indonesian hardwood is Bangkirai provided this is heartwood.
A technical data sheet from the Australian timber base sheds some light on the termite resistance of Merbau and can be found at https://www.timber.net.au/?option=com_species&name=Merbau&Itemid=441  This article clearly indicates that only Merbau heartwood is termite resistant.

Rationale

Claiming that a wooden house built from Bangkirai or Merbau is 100% termite resistant is a deceiving statement, since not one supplier will supply heartwood only, hence they supply a mix of sapwood (very termite sensitive) and heartwood (not susceptible to termite attacks). As a result the house is built with this mix of sapwood and heartwood and thus.....not 100% termite resistant      
Main conclusion: One shall not automatically believe that a house built from Indonesian hardwood is 100% safe to termite attacks, at least we are not promoting this. By ruling out the extremely expensive Bojonegoro Teak and the fact that Iron wood is prohibited from being exported, Bangkirai or Merbau heartwood in combination with a termimesh system or a termite barrier application will give optimum protection. Our statement that Bangkirai and Merbau sapwood is not termite resistant is therefore fully underlined by the above articles.

 termites-eating-sap-wood

 Termites eating sap wood

We have a proper and effective solution for our clients in the Northern territory of Australia where the dangerous Mastotermes flourishes.

(*) STOP PRESS: We can guarantee termite resistance:

On April 16, 2012 we signed an exclusive contract with one of the Balinese timber suppliers allowing us to select as much as possible Bangkirai heartwood from his stock yard at no extra costs, provided we buy all Bangkirai that we need for our projects from his company. This will put us in the unique position to guarantee that we are now able to fabricate timber houses, using as much as poissible Bangkirai heartwood (with a luttle mix of sap wood perhaps), which is definitely 100% termite resistant when in combination with our in-house (secret) developed termite treatment system. 

 

BORERS

Woodboring beetles most often attack dying or dead trees. In forest settings, they are important in the turnover of trees by culling weak trees, thus allowing new growth to occur. They are also important as primary decomposers of trees within forest systems, allowing for the recycling of nutrients locked away in the relatively decay-resilient woody material of trees. Though the vast majority of woodboring beetles are ecologically important and economically benign, some species can become economic pests by attacking relatively healthy trees (e.g. Asian longhorned beetle, emerald ash borer) or by infesting downed trees in lumber yards. Species such as the Asian longhorned beetle and the emerald ash borer are examples of invasive species that threaten nature forest ecosystems.
   Borer-dust

If you see dust like this you have borers
 

 Borer-holes

Typical borer holes


Borers and hardwood

Borers that may attack dry hardwood are:

Lyctid borer (Powder post borer)

Powder-post-borer

These borers produce a very fine powdery dust, similar in consistency to talc attack the sapwood of certain hardwood timbers cause serious structural weakening in timber that has a high sapwood content.

Borer larvae (grubs)

Powder-post-borer larvea

Borer larvea may feed on new timber and emerge as adults once the timber dries out.

Anobiid borer

Anobiid-borer

These borers produce a gritty 'salt like' dust. There are many different species of this borer, but two significant ones are listed - Anobium punctatum, the common furniture beetle, and Calymmaderus incisus, the Queensland pine beetle.

Anobium punctatum (Common furniture beetle)

Anomium-punctatum

These borers attack furniture, structural timbers, flooring and decorative wood work. Prefer old, well seasoned timber, sap woods

 

FUNGI

A wood destroying fungus (fungi, plural) causes more damage to structures than all the fires, floods, and termites combined! Wood decaying fungus requires four fundamentals to survive which are oxygen, favorable temperatures, water, and food. Fungus occurs generally when the moisture content of wood exceeds 20 to 30 percent, coupled with optimal temperatures (32˚ – 90˚ F), an adequate supply of oxygen and a suitable source of energy and nutrients. Fungus is a plant that lacks chlorophyll (which gives a leef its color). Unable to manufacture its own food, it feeds off of cells in the wood. The fungus secretes enzymes that break down the wood into usable food. Fungi will significantly reduce the strength of the wood, if the condition continues over a period of time.

 

 

Durability against rot
(when unprotected and in ground contact)


Full-indicatorFull-indicatorFull-indicatorFull-indicator = Very durable

Full-indicatorFull-indicatorFull-indicator = Durable

Full-indicatorFull-indicator = Moderate

Full-indicator = Non durable


Fungi and hardwood

White rot
White rot breaks down all major wood components (cellulose, hemicelluloses and lignin) more or less simultaneously, and commonly causes rotted wood to feel moist, soft and spongy, or stringy and to appear white bleached. The strength of the infested wood decreases gradually until it becomes spongy to the touch and stringy when broken.

Bangkirai = Full-indicatorFull-indicatorFull-indicator, Merbau = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Camphor = Full-indicatorFull-indicator, kempas = Full-indicatorFull-indicator, Nyatoh = Full-indicator, Keruing = Full-indicatorFull-indicator

Brown rot
Brown rot primarily decays the cellulose and hemicelluloses in wood, leaving a brown residue of lignin, the substance which holds the cells together. Wood affected by brown rot is usually dry and fragile, readily crumbles into cubes because of longitudinal and transverse cracks (tending to crack across the grain). Infected wood may be greatly weakened, even before any external evidence of decay can be seen. Brown rot is generally more serious than white rot. Old infestations of brown rot which have dried out will turn to powder when crushed. They are often labeled as "dry rot." This common term is deceiving, because dry wood will not rot! Actually, wood kept dry will never decay. 

Bangkirai = Full-indicatorFull-indicatorFull-indicator, Merbau = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Camphor = Full-indicatorFull-indicator, kempas = Full-indicatorFull-indicator, Nyatoh = Full-indicator, Keruing = Full-indicatorFull-indicator

Poria incrassata
Poria incrassata is a brown rot fungus. Whereas most wood decaying fungi must rely on a water leak, or ground contact condition, to obtain the required water, poria incrassata has developed specialized root-like water-conducting tubes, called rhizomorphs, which allow it to transport water from the soil to the wood.  Therefore, even in situations where wood is protected from rainfall, and no leaks exist, wood can still be decayed by poria. Once established, it can quickly spread through a building and destroy large areas of flooring and walls in as little as a year or two. 

Bangkirai = Full-indicatorFull-indicatorFull-indicatorFull-indicator,, Merbau = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Camphor = Full-indicatorFull-indicatorFull-indicator, kempas = Full-indicatorFull-indicator, Nyatoh = Full-indicatorFull-indicator,
Keruing = Full-indicatorFull-indicator

Soft rot fungi
Soft rot fungi degrade only the cellulose and hemicelluloses, and typically occur in wood of high water content and high nitrogen content. Soft rot fungi look like brown rot. They are most commonly found in rotting window frames, wet floor boards and fence posts, etc., where nitrogen is recruited from soil or from atmospheric contamination. Some of these fungi are common decomposers of cellulose in soil and they are the least specialized of the wood decaying fungi

Bangkirai = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Merbau = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Camphor = Full-indicatorFull-indicatorFull-indicator, kempas = Full-indicatorFull-indicatorFull-indicator, Nyatoh = Full-indicatorFull-indicator,
Keruing = Full-indicatorFull-indicatorFull-indicator

Mold
Molds are microscopic fungi that live on plant or animal matter. The presence of surface molds can be confused with wood decaying fungi. Although mold organisms may discolor the wood, they do not break down wood fibers and thus do not weaken its structure. However, these organisms could indicate a moisture level in the wood high enough to also support the growth of wood decay fungi. Molds also can increase the capacity of wood to absorb moisture, opening the door for an attack by wood decay fungi. Moisture control methods used to inhibit wood decay fungi will also eliminate conditions favorable for mold to grow. 

Bangkirai = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Merbau = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Camphor = Full-indicatorFull-indicatorFull-indicatorFull-indicator, kempas = Full-indicatorFull-indicatorFull-indicatorFull-indicator,
Nyatoh = Full-indicatorFull-indicatorFull-indicatorFull-indicator, Keruing = Full-indicatorFull-indicatorFull-indicatorFull-indicator

MAIN CONCLUSION: Our hardwood, used for structrual elements, flooring and/or sidings is safe to borers and mold. For optimum termite protection log on to the < special termite page >  

 

 

 

Prefab World Bali

Reviews from Prefab World Bali

"Prefabworld Bali International is doing an excellent job of modeling the 3-D finite element frame structure in STAAD and now analyzing the individual members to ensure that they are not overstressed. I have just completed a review of the column analysis for the primary columns supporting the roof, and it is well presented and clearly shows the members are adequate size. I have not seen anything like this before the way this report was presented and prepared with the vast knowledge behind. This type of analysis would not have been possible by hand calculation because of the complexity of the structure. Job well done Prefabworld Bali International".
Review from: Professor Ian Robertson, University of Hawaii
Project: 400 m2 dwelling for Maui
Date: 12-06-2012.
Rating: 5 out of 5.

Read more testimonials from Prefabworld Bali International: click here
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