FAQ - Frequently Asked Questions

Frequent questions about the wood drying

The answers of BASCHILD experts to the frequently asked questions.

Have you got a different question? Contact us!

A freshly cut tree contains a high volume of water that can obstruct processing and conservation.

The excess water in the wood, called the initial moisture content must be removed through the drying process, which brings the moisture content of the wood to the final moisture content value, necessary if the wood is intended for commercial use.

The drying process must not damage the timber.

Wood is a hygroscopic material with a natural tendency to absorb or give off moisture to balance out with its surrounding environment.

For this reason, wood must reach a final moisture content value during the drying processs that is as near as possible to the moisture content value of the environment where it will be used.

Therefore a suitable artificial drying process can help to avoid any timber alteration after processing, increasing the commercial value.

Among timber drying technologies, the conventional hot air drying is undoubtedly the most widespread, thanks to the excellent relationship between investment cost and productivity.

The wood drying kilns BASCHILD TDK fall into this category.

The artificial drying is a very important step in the wood processing, cause involves considerable advantages in comparison with the natural drying, like waste volume and stocking time reduction.

For the drying process an appropriate climate is created in special drying kilns that helps the gradual and controlled removal of the moisture in the wood.

The main parameters to be regulated, according on the different wood characteristics, include: temperature, air moisture, ventilation.

The temperatures vary according to the characteristics of the wood to be dried.

The air humidity is a deciding factor for the drying process and for the final quality of the wood: a too fast drying process (very low air humidity) causes serious damages to the timber, such as veins in the wood, twisting, internal cracking and splitting, whereas a too slow drying process (high humidity levels) can cause mould and fungi formation.

The air plays a double role: it carries the heat from the heating system to the wood and it absorbs the moisture.

BASCHILD TDK kilns ensure a high quality drying cycle, cause they manage at best the process variables.

The main objective of the wood drying kiln is to reduce the moisture in the wood as rapidly as possible.

The operating principle of the dryer consists in blowing hot air through the wood stacks to evaporate the moisture inside the wood.

Temperature and moisture in the air are electronically controlled and regulated.

The air is circulated inside the kiln using reversible fans. 

The air absorbs the moisture from the wood as it passes through the wood stacks.

This process makes the air moist and cool and it is then returned to its original state by: heating, partial exchange of the air and air humidification.

Conventional drying kilns, based on elementary physical principles, use hot air to extract moisture from wood and pass it to air.

The BASCHILD TDK dryers apply this concept to aluminum kilns, equipped with systems of heating, ventilation, air recirculation and humidification.

In this way you can vary the temperature and the air moisture degree inside the kiln and, as a consequence, modify the wood temperature and humidity.

The drying time parameter is difficult to foresee, as it changes according to the type of wood, the thickness and many other factors.

For this reason, it can only be calculated approximately.

The drying time is influenced by: structure and density of the wood, thickness of the wood, moisture levels in the wood, external air humidity levels, temperature, gradient, air flow through the wood stacks and type of drying kiln.

The BASCHILD TDK kilns are customized according to the features of the wood to be dried.

Aims of the wood thermal modification (heat treatment) are: color changing, redevelopment of material with color defects and enhancement of wood species with low commercial value.   

The thermal treatment can be performed only on already dried material and it normally the semi-finished product is treated.

The heat treatment brings to different results according to the wood essence, with a clear distinction between deciduous and coniferous.

The main application of heat treatment is currently in the garden furnishing, floors and exterior coverings, the parquet (as a top layer) and in the marine industry, but the use can be extended also to other industry sectors.

BASCHILD has developed the market of high temperature drying kilns, that give wood new aesthetic and functional characteristics.

So thermal treatment cycles are made in special ATK kilns, that have got a high technological content, for mechanics and process management.

The heating temperature causes a decrease in the wood weight, due to the loss of water and volatile extracts.

As the temperature increases, chemical changes take place in the macromolecular components of the cellular wall, leading to color changes.

The timber thermal treatment is performed when temperature is between 180°C and 260°C.

In fact below 140°C only slight changes to wood properties happen, whereas above 300°C the temperature causes a severe timber degradation.

The pre-drying process lowers wood moisture content till 20÷25%, thanks to the kiln treatment at a constant temperature and humidity.

The pre-drying process can not replace the drying cycle, but it's an alternative to the conventional storage in the yard.

In fact the pre-dried wood must be dried to obtain moisture contents below 20%.

PDK pre-drying kilns are intended to store large timber volumes, preserving them from tension and cracks.


Aim of the vaporization is the improvement of the wood aesthetic characteristics.

Inside a closed chamber, saturated with water vapor, the wood is vaporized and the time needed is directly proportional to the desired color intensity.

The action of steam, with air temperature at +90°C, dissolves salts and sugars in wood, varying its natural color. 

The steaming process mostly applies to certain wood essences, like beech, maple, larch, and bamboo, but it can also be extended to other species.

To vaporize wood, BASCHILD provides two product lines: DVK-D direct steaming chambers and DVK-I indirect steaming chambers.

Steaming chambers are used to vary the wood color thanks to the action of steam.

So the main parameters are temperature and steaming time.

The vaporization process usually consists of two steps, for a total duration of 10-15 hours. 

During the first phase the steam is brought to an intermediate temperature (e.g. +70°C), maintained for a few hours.

Afterwards the gradation is increased up to the maximum point of 96°C and held constant for a few hours.

Finally the wood is left to cool naturally, so that it doesn't exceed a temperature of +40°C.

To obtain a high quality vaporization, BASCHILD offers two product lines: DVK-D direct steaming chambers and DVK-I indirect steaming chambers.

The technical manual must be conserved for the entire duration of the drying kiln life.

In case of sale, the used kiln must be accompanied by its own manual.

BASCHILD dryers are customized, so each manual is unique.

Contact us to request a copy of the manual.

We are at your disposal.

Over the years BASCHILD controllers have been improved up to the current system BASCHILD ZOOM.

Read the page concerning previous control systems and contact us if you need the user manual or further details.

BASCHILD kilns are custom-designed.

Our team of experts defines the configuration according to the final customer needs.

In the planning phase several details are discussed.

In case of drying kiln, the first aspects to deal with are:

  • wood species to be treated;
  • monthly / annual production volume;
  • minimum and maximum thickness;
  • minimum and maximum length;
  • initial and final moisture content;
  • loading method (forklift, cart on rails);
  • heating energy (steam, hot water, diathermic oil, gas).

In case of steaming chamber, specifications of thickness and moisture content are not needed.

Whether you still know these details or not, you can write BASCHILD to request a free custom quote.

Our team is at your disposal. 

Request your quote now!

BASCHILD kilns are custom-designed.

So there is not a price list with standard sizes.

This is advantageous, cause the kiln takes shape according to your needs.

Request your custom quote now!

BASCHILD has got an extensive network of dealers, to promptly provide specific assistance.

Browse the list of branches and dealers and find out the nearest service center.

BASCHILD kilns are currently equipped with the innovative software ZOOM.

Any other controller is out of production.

For further details you can browse the list of the previous operative systems.

BASCHILD offers the possibility to replace the old controller on favorable terms.

Request your custom quote now!

You can darken wood in a natural way without chemical products.

For this purpose BASCHILD offers several solutions.

ATK high temperature kilns thermally treat wood to give it a dark color and make it more resistant to atmospheric agents.

That's why thermal wood is particularly suitable for the outdoor use.

Furthermore the customer can customize TDK drying kilns with the LSE technology, that makes possible the light steaming of the wood. 

The normal activity of the drying kiln makes noise.

To reduce the decibels BASCHILD suggests the innovative technology DB-REDUCER.

Odor emissions are a physiological consequence of the high temperature treatments on organic matter.

To reduce these effects, the BASCHILD high temperature kilns are equipped with the special NOX-WALL technology, that filters the odors emitted by the heat treated wood.   

Broad-leaved (hardwood) and conifers (softwood) differ in cell structure and chemical composition.

Also size changes, due to the variations in the amount of water present in a piece of wood, are not the same, either within the same species of wood, or between different species.

Furthermore denser wood is more difficult to dry, whereas light woods offer less resistance to the movement and are more easily treatable.

The wood density can be affected by different factors: the species, the climate in the area where the tree was grown and the moisture conditions depending on the time that has passed since the tree was cut.

Finally the wood essences can be grouped into four (relatively homogeneous) categories, according to the electrical resistance, that plays a key role during the drying process.

BASCHILD drying kilns respect the peculiarities of each type of wood, to ensure an effective and quality treatment.

Each kiln is specially designed according to the wood species to be dryed and the software BASCHILD ZOOM allows users to set up a specific treatment based on the features of the timber.

Usually BASCHILD doesn't deal with second hand drying kilns and steaming chambers.

In case of availability, we can put you in touch with the customer, who wants to sell his kilns.

Usually BASCHILD doesn't deal with second hand high temperature kilns.

Our high temperature kilns are totally welded by hand, so any attempt to move them is difficult.

It's impossible to disassemble a BASCHILD high temperature kiln, without destroying the stainless steel walls.

For this reason we advise against buying a used high temperature kiln.

Interested in the heat treatment with low budget?

Request a free quote, customized according to your needs.

It is possible to build a DIY drying kiln, as an attempt to limit investments.

Nevertheless you need to buy raw material, like aluminum.

Furthermore you often risk to loose the value of the wood inside the kiln, because of a poor drying process.

Are you thinking to build a DIY drying kiln to save money?

Before choosing this option, request a free quote.

Our kilns are customized and can be adapted to your requirements.

The control system ZOOM can be installed on old drying kilns and vaporizers.

BASCHILD team of experts prepare a customized project starting from the existing kilns, to improve efficiency and performances.

Request your custom quote now!

ATK high temperature kilns are designed for your needs.

BASCHILD technicians are at your disposal.

Tell us your needs and you will receive a free custom quotation.

Request your quote now!

The ventilation plays a key role in the drying process, cause it profoundly affects the quality of the dryed wood.

That's why BASCHILD has developed technologies capable to optimize the ventilation.

Learn more about technologies to improve the wood drying quality.

The humidification is a determining factor for the success of the drying process.

A bad humidification can favor the appearance of wood color defects (like stains or discolorations)

To ensure a fast and quality humidification , BASCHILD has introduced important innovations .

Learn more about the technologies to optimize the humidification and avoid wood aesthetic defects.

Drying kilns have a significant environmental impact.

So, the attempt to reduce the consumption of the energy sources needed for their operation, is an ambitious goal.

BASCHILD has developed several innovations to eliminate waste and reduce the consumption of fuel and electricity absorbed.

Learn more about BASCHILD technologies for the energy saving.

To reduce the power consumption of the drying kilns, BASCHILD offers several innovative solutions.

TDK drying kilns avoid excessive consumptions and significantly reduce the energy resources used. 

Learn more about energy-saving technologies.

Stains are aesthetic timber defects, mainly due to an improper humidification.

To avoid the appearance of color defects, BASCHILD has developed technologies that ensure a uniform wood color.

When designing drying kilns or high temperature kilns is necessary to respect the limits established by law concerning pollution and decibels.

This is even more important for sawmills close to residential areas, where often are more restrictions.

To meet these requirements, BASCHILD uses technologies that reduce noise, olfactory and polluting emissions.

The law establishes the amount of Volatile Organic Compounds (VOC) to be released by the drying kiln into the surrounding environment.

Therefore polluting emissions can not exceed a certain threshold.

Thanks to the innovative technology NOX-WALL, BASCHILD kilns dry in accordance with the limits set by law.


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