Show me your Ulin and I'll tell you who you are

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With today internet access everybody suddenly became an expert in every single possible subject and work.

It is unfortunately the same for reclaim wood.

As it comes out, we mostly only know what we think we know but don’t know much in the end. This over confidence leads us to buy good material and do good deals of fake stuff that we ultimately regret.

How many times have we been contacted by desperate hotels, restaurants or individuals because they had problems with their “reclaim Ulin from Kalimantandecking and/or flooring. Once on site you realize the reasons of that despair. Varnish falling off (only a full sanding and recoating can help, no cheap solution), fully cracked wood (impossible to fix) not to mention long splits (sometimes up to 40% of the board!!!) and rusty nails (discoloring the wood in the process).

The worst being it isn’t even Ulin from Kalimantan and most often not even reclaim.

A commonly sold Ulin Kalimantan so called reclaim is what we call “rendaman”. It is a process in which they cut boards size planks into new Ulin trunk, put some nails on it, oil it and put it into mud for a couple of month. Voila! The real Ulin Kalimantan board will look, from the outside, like a genuine reclaim board. But it is not at all.

Wood continues to move as it is in contact with its surrounding environment (humidity, temperature). Reclaim wood tend to be an already dry wood and will move less. A new wood is still full of all its elements and not yet at EMC meaning disastrous consequences for construction site (cupping, bending, bowing, crack, split). It will look beautiful the first few months…unfortunately only the first few months then you are in for a financial treat to fix your nightmare decking or flooring.

A recent test on our facebook page was asking to recognize an Ulin plank in between two boards. One was Bengkirai, the other was Ulin. 70% of the voters choose the Bengkirai plank as being Ulin…

Bengkirai can look like Ulin but its quality as an outdoor product are far behind those of Ulin Kalimantan.

I write Ulin Kalimantan because you can also find Ulin Sulawesi. This last Ulin is of a much lower quality than the one from Kalimantan and will tend to crack quickly if not to split. Would you like to know more about this Ulin Sulawesi you can read this interesting article.

Luckily some honest sellers are offering a good quality wood in its raw form or processed but I’d advise you to make sure 100% that you know what you are buying. Dirty and muddy doesn’t mean reclaim.

On a more personal note, out of curiosity I went somewhere in Bali where you can find many reclaim Ulin sellers. I found half of it to be rendaman, other sellers were offering real poor quality but genuinely reclaim Ulin (can’t tell if it was from Sulawesi or Kalimantan) and only one person was selling genuine reclaim Ulin of good quality. Took us a full day to go around all places and found only one place where we could have bought good wood.

On a more commercial note, we at Kaltimber, offer real reclaim Ulin from Kalimantan. We work with the Forest ministry to get all our legal documentations, we know where the wood comes from and what structure it was dismantled from. We don’t do rendaman or Ulin Sulawesi, our focus is genuine reclaim Ulin from Kalimantan Timur. We offer years of experience and are always happy to advise and help for free.

Buying wood should be a non stressful investment and enjoying it should last for decades.

Our Ulin being checked before being given green light to leave Kalimantan

Our Ulin being checked before being given green light to leave Kalimantan

Ulin vs Ulin

So many customers get tricked and buy real reclaimed Ulin which is nether real nor reclaimed and not even Ulin.
We offer a wide range of services at Kaltimber and we can guarantee as well as prove the origin and type of wood we sale.
Don't fall for super cheap price offer while buying a rare material.
Next Monday we will publish an article regarding Ulin and the risks of buying fake reclaim.


What is the EMC and why is it important

The equilibrium moisture content (EMC) of a material surrounded at least partially by air is the moisture content at which the material is neither gaining nor losing moisture. The value of the EMC depends on the material and the relative humidity and temperature of the air with which it is in contact. The speed with which it is approached depends on the properties of the material, the surface-area-to-volume ratio of its shape, and the speed with which humidity is carried away or towards the material (e.g. diffusion in stagnant air or convection in moving air).

For anyone who works with wood products on a regular basis, there are a couple of reasons why it is important to know the point at which wood will reach its EMC, as well as the average moisture content of the region where the wood will be used.

As wood absorbs or bleeds moisture, it will expand or contract. The more moisture that is absorbed or displaced, the more severe the expansion/contraction of the wood product. This can cause, as seen in previous topics, cupping, bowing and another deformation of wood as well as cracks and even splits.

It can take a few days for wood to fully acclimate to a given environment, depending on the original moisture content of the wood, the temperature of the new environment, and the relative humidity of the area. Generally speaking, the greater the difference between the moisture content of the wood and the EMC point of the wood, the longer it will take to fully acclimate.

Moisture meter as used in Kaltimber

Moisture meter as used in Kaltimber

Make sure to check with your wood supplier what is their wood EMC and what the humidity of its future environment is.

Reclaim wood such as Ulin tend to be already really dry but its high density makes it harder to acclimate to a new environment. We are not talking about a few days in this specific case but more a couple of weeks to avoid any long term issue.

Hardwood and Softwood, what is the difference?

red elm end grain

Hardwood is not necessarily a harder material (more dense) and a softwood is not necessarily a softer material (less dense).

Different types of construction projects call for different kinds of timber, both hardwood and softwood are used for everything from structural to decorative.

Softwood and hardwood are distinguished botanically in terms of their reproduction, not by their end use or appearance. All trees reproduce by producing seeds, but the seed structure varies.

Softwood trees are known as a gymnosperm. They reproduce by forming cones which emit pollen to be spread by the wind to other trees. Pollinated trees form naked seeds which are dropped to the ground or borne on the wind so that new trees can grow elsewhere.

A hardwood is an angiosperm. Angiosperms usually form flowers to reproduce. Birds and insects attracted to the flowers carry the pollen to other trees and when fertilized the trees form fruits or nuts and seeds.

The hardwood/softwood terminology does make some sense. Evergreens do tend to be less dense than deciduous trees, and therefore easier to cut, while most hardwoods tend to be more dense, and therefore sturdier. In practical terms, this denseness also means that the wood will split if you pound a nail into it. Thus you need to drill screw or bolt holes to fasten hardwood together. But structural lumber is soft and light, accepts nails easily without splitting and thus is great for general construction.

To sum up

Hardwood tend to be darker, heavier, more expensive, last several decades, naturally resistant to weather.
Softwood tend to be lighter in color, lighter weight, cheaper, last for a decade or so and can be weather resistant but needs to be treated.

Knowledge: countertop

A countertop is a horizontal work surface in kitchens or other food preparation areas, bathrooms or lavatories, and workrooms in general. It is frequently, but not only, installed upon and supported by cabinets. The surface is positioned at an ergonomic height for the user and the particular task for which it is designed. A countertop may be constructed of various materials with different attributes of functionality, durability, and aesthetics. The countertop may have built-in applicances, or accessory items relative to the intended application.

Countertops come in a variety of materials such as:

Natural stones, Silicate mineral, Wood (Hardwood & Softwood), Crafted glass, Manufactured materials (Concrete, Compressed paper or fiber, Cultured marble, High pressure laminates) and many more.

Kitchen countertop and its cabinet

Kitchen countertop and its cabinet


Wooden countertops can come in a variety of designs ranging from butcher block to joined planks to single wide stave. Wood is considered to be the most eco-friendly option when it comes to choosing a kitchen countertop as wood is a renewable resource. Wood countertops must be thoroughly cleaned and disinfected after contact with foods such as raw meat. Although the use of wooden work surfaces is prohibited in commercial food production areas in the EU, and the US Department of Agriculture advises against the use of wooden chopping boards, research by the Food Research Institute at the University of Wisconsin has shown that wooden work surfaces are no more dangerous, and in some cases safer than plastic alternatives. They have shown that while bacteria do get absorbed by the wood, they do not multiply and eventually die. While brand new plastic work surfaces are indeed easy to disinfect, once they have become heavily knife scarred they are nearly impossible to completely disinfect. This is not a problem with wooden work surfaces where the number of knife cuts made little difference.

We, at Kaltimber, produce some custom countertop with three different types of finishing (Smooth, Semi-smooth , Rustic) and two different thicknesses (2cm and 4cm). Feel free to contact us to get your personalized quote today!

Reclaim Ulin countertop

Reclaim Ulin countertop

Wood-decay fungus

Brown rot

Brown rot

A wood-decay fungus is any species of fungus that digests moist wood, causing it to rot. Some species of wood-decay fungi attack dead wood, such as brown rot, and some are parasitic and colonize living trees. Excessive moisture in wood is required for fungal colonization and proliferation. Fungi that not only grow on wood but permeate its fibrous structure and actually cause decay, are called lignicolous fungi. In nature, this process serves to break down complex molecules and return nutrients to the soil. Various lignicolous fungi consume wood in various ways; for example, some attack the carbohydrates in wood and some others decay lignin (structural materials in the support tissues of vascular plants). The rate of decay of wooden materials in various climates can be estimated by empirical models.

Wood-decay fungi can be classified according to the type of decay that they cause. The best-known types are brown rot, soft rot, and white rot. Each produce different enzymes, can degrade different plant materials, and can colonize different environmental niches.

Brown-rot fungi break down hemicellulose and cellulose that form the wood structure. In this type of decay, the wood shrinks, shows a brown discoloration, and cracks into roughly cubical pieces, a phenomenon termed cubical fracture. Brown-rot fungi of particular economic importance (3 main fungi) may attack timber in buildings. Dry rot is a generic name for certain species of brown-rot fungi.

There are very few brown rot fungi in tropical climates.

Soft-rot fungi leads to the formation of microscopic cavities inside the wood, and sometimes to a discoloration and cracking pattern similar to brown rot.

Soft-rot fungi are able to colonize conditions that are too hot, cold or wet for brown or white-rot to inhabit. They can also decompose woods with high levels of compounds that are resistant to biological attack. Bark in woody plants contains a high concentration of tannin, which is difficult for fungi to decompose, and suberin (waterproofing waxy substance) which may act as a microbial barrier.

White rots break down lignin and cellulose and commonly cause rotted wood to feel moist, soft, spongy, or stringy and appear white or yellow. There are many different enzymes that are involved in the decay of wood by white-rot fungi. White-rot fungi are grown all over the world as a source of food – for example the shiitake mushroom, which in 2003 comprised approximately 25% of total mushroom production.






Source wikipedia


Wall panel

A wall panel is single piece of material, usually flat and cut into a rectangular shape, that serves as the visible and exposed covering for a wall. Wall panels are functional as well as decorative, providing insulation and soundproofing, combined with uniformity of appearance, along with some measure of durability or ease of replaceability. There is no set size limit for a piece of material fulfilling these functions, the maximum practical size for wall panels has been suggested to be 7m by 2.5m, to allow for transportation. Our panels are made of either 50x50cm or 100x100cm reclaimed Kalimantan Ulin or Javanese Teak fixed on a 6mm plywood. Variable thickness, width and length of the wood creates a beautiful and decorative pattern.

Use of wall panels can reduce construction costs by providing a consistent appearance to the paneled surface without requiring the application of paint or another finishing material. Wall panels may be finished on only one side, if the other side is going to be against a brick or concrete wall, or a comparable structure. Alternately, the panels may, if assembled to an appropriate framework, substitute for having any other kind of wall at all. Holes may be cut or drilled into a wall panel to accommodate electrical outlets and other devices coming out of the wall.

There is a new type of eco friendly 3d wall panel made out of the fibrous residue of sugarcane. This fibres of crushed sugarcane stalks, remaining after raw sugar is extracted from the juice of the sugarcane by shredding it, is now the raw material, called bagasse, that forms the base of this easily installed eco friendly product. The raw material used for these 3d wall panel is 100% recycled, compostable and is therefore 100% biodegradable. In addition, the use of reclaim wood provides yet another 100% eco-friendly solution.

50x50cm wall panel made of 2x3cm reclaim Ulin

50x50cm wall panel made of 2x3cm reclaim Ulin

Forest to protect cities from earthquake

The deflected waves to protect a building can destroy the neighbor and, among the famous surface seismic waves known by seismologists  as Rayleigh waves, some have wave lengths large enough not to be affected by the already envisaged seismic invisibility systems. Fortunately, these problems seem to be able to be overcome using ... trees!

Experiments carried out in France with a small pine forest not far from the campus of the Université Joseph-Fourier in Grenoble, together with numerical simulations, confirm that the trees can behave as resonators rebroadcasting the waves of Rayleigh in a certain frequency band in response to the arrival of these of an earthquake. In the end, they are sent deep into the ground, even for large wavelengths. Oddly enough, the most effective protection is obtained with trees planted in a dense and random way. It improves again by covering a larger frequency band if the trees are arranged with decreasing heights.

Yet there is a problem: at the moment, the concept only works if the waves arrive from two directions only. But the researchers are confident. They'll blow up that lock.

Earthquake damaged road

Earthquake damaged road

Joinery, what is a mortise and tenon?

The mortise and tenon joint has been used for thousands of years by woodworkers around the world to join pieces of wood, mainly when the adjoining pieces connect at an angle of 90°. In its basic form it is both simple and strong. Although there are many joint variations, the basic mortise and tenon comprises two components: the mortise hole and the tenon tongue. The tenon, formed on the end of a member generally referred to as a rail, is inserted into a square or rectangular hole cut into the corresponding member. The tenon is cut to fit the mortise hole exactly and usually has shoulders that seat when the joint fully enters the mortise hole. The joint may be glued, pinned, or wedged to lock it in place.

This joint is also used with other materials. For example, it is a traditional method for stonemasons and blacksmiths.

Mortise and Tenon joinery technique

Mortise and Tenon joinery technique


A mortise is a cavity cut into a timber to receive a tenon. There are several kinds of mortise:

Open mortise: a mortise that has only three sides (usually open on top of the wood)

Stub mortise: a shallow mortise, the depth of which depends on the size of the timber; also a mortise that does not go through the workpiece (as opposed to a "through mortise").

Through mortise: a mortise that passes entirely through a piece.

Wedged half-dovetail : a mortise in which the back is wider, or taller, than the front, or opening. The space for the wedge initially allows room for the tenon to be inserted; the presence of the wedge, after the tenon has been engaged, prevents its withdrawal.

Through-wedged half-dovetail: a wedged half-dovetail mortise that passes entirely through the piece.

A tenon is a projection on the end of a timber for insertion into a mortise. Usually the tenon is taller than it is wide. There are several kinds of tenon:

Stub tenon: short, the depth of which depends on the size of the timber; also a tenon that is shorter than the width of the mortised piece so the tenon does not show (as opposed to a "through tenon").

Through tenon: a tenon that passes entirely through the piece of wood it is inserted into, being clearly visible on the back side.

Loose tenon: a tenon that is a separate part of the joint, as opposed to a fixed tenon that is an integral part of one of the pieces to be joined.

Biscuit tenon: a thin oval piece of wood, shaped like a biscuit.

Pegged (or pinned) tenon: the joint is strengthened by driving a peg or dowel pin through one or more holes drilled through mortise side wall and tenon. This is common in timber framing joints

Tusk tenon: a kind of mortise and tenon joint that uses a wedge-shaped key to hold the joint together.

There are other types of mortises and tenon, feel free to add in the comments and/or share pictures.

Generally the size of the mortise and tenon is related to the thickness of the timbers. It is considered good practice to proportion the tenon as one third the thickness of the rail, or as close to this as is practical.


This is an ancient joint dating back 7,000 years. The first examples, tusked joints, were found in a well near Leipzig - the world's oldest intact wooden architecture. It has also been found joining the wooden planks of the "Khufu ship",a 43.6 m long vessel sealed into a pit in the Giza pyramid complex of the Fourth Dynasty around 2500 BC. The oldest known use dates from the Early Neolithic Linear Pottery culture, where it was used in the constructing of the wooden lining of water wells.

It has also been found in ancient furniture from archaeological sites in the Middle East, Europe and Asia. Many instances are found, for example, in ruins of houses in the Silk Road kingdom of Cadota, dating from the first to the fourth century BC. In traditional Chinese architecture, wood components, such as beams, brackets, roof frames and struts, were made to interlock with perfect fit, without using fasteners or glues, enabling the wood to expand and contract according to humidity. Archaeological evidence from Chinese sites shows that, by the end of the Neolithic, mortise-and-tenon joinery was employed in Chinese construction.

The thirty sarsen stones of Stonehenge were dressed and fashioned with mortise-and-tenon joints before they were erected between 2600 and 2400 BC.





Source Wikipedia


Why you should listen

tree forest life

A professor of forest ecology at the University of British Columbia's Department of Forest and Conservation Sciences in Vancouver, Suzanne Simard studies the surprising and delicate complexity in nature. Her main focus is on the below-ground fungal networks that connect trees and facilitate underground inter-tree communication and interaction. Her team's analysis revealed that the fungi networks move water, carbon and nutrients such as nitrogen between and among trees as well as across species. The research has demonstrated that these complex, symbiotic networks in our forests -- at the hub of which stand what she calls the "mother trees" -- mimic our own neural and social networks. This groundbreaking work on symbiotic plant communication has far-reaching implications in both the forestry and agricultural industries, in particular concerning sustainable stewardship of forests and the plant’s resistance to pathogens. She works primarily in forests, but also grasslands, wetlands, tundra and alpine ecosystems.