Decking for terrace, balcony, platforms and similar is the most important application for modified wood such as thermally modified timber, acetylated and furfurylated timber, followed by façade cladding including shading elements. These applications are well established and the main sales for modified wood products (Scheiding 2018). The use of modified timber for window scantlings has been introduced by some suppliers, but current data on real sales are not available. Considerable amounts of thermally modified timber are used for sash cores of polyurethane-coated windows. Modified wood is also used for garden furniture, playground devices, or other gardening and landscaping purposes, like fences, poles, or screens. Thermally modified timber is because of its aesthetic appearance also used for interior applications, mainly for flooring and panelling, which is not the case for acetylated and furfurylated timber. For interiors, existing requirements on emission should be considered for

Modified wood has gained market entry across a range of Use Classes, depending on the levels of treatment and how they alter the durability and moisture exclusion levels of the treated material. Some examples of these

Thermally modifed timber incl. aged timber 535,000 Densified wood 2,000 Acetylated timber incl. production under development in UK 120,000 Furfurylated timber incl. production under development in Belgium 45,000 Other chemical methods 35,000

*Table 4: Estimated production volumes the nearest coming years for some specific types of modified wood*

**Use Class 3**

**Use Class 4**

24

within data compiled here.

thermally modified timber.

**Uses of modified wood**

modified wood in Use Classes are given in Figure 17.

*Figure 17: Examples of modified wood in Use Classes 1-4*

27

**Number of tested materials**

**Performance**

2 InnoRenew CoE, Livade 6, Izola, Slovenia<EMAIL_ADDRESS>
**Anna SANDAK¹, Jakub SANDAK¹,**

cnr.it<EMAIL_ADDRESS>
**Introduction**

bio-based materials in buildings.

**BIO4ever project**

**Wood modification**

impregnation

modification

natural chemical composites coating & surface treatments

thermal modification hybrid

combination of at least two different treatments (Table 4).

**technology Samples examples**

*Table 5: Categories of bio-based facade materials tested within BIO4ever (Sandak et al. 2018)*

wood, bamboo acetylation, furfurylation

**of modified wood**

**The BIO4ever project - how to convince**

**people to use bio-based building materials?**

¹ CNR-IVALSA, via Biasi 75, San Michele all'Adige, Italy<EMAIL_ADDRESS><EMAIL_ADDRESS>petrillo@ivalsa.

Today's bio-based building materials, even if well characterized from the technical point of view, often lack reliable models describing performance during their service life. The overall goal of the BIO4ever project is to contribute to public awareness, by demonstrating the environmental benefits to be gained from the knowledge-based use of

³ Wroclaw University of Science and Technology, ul. Prusa 53/55, Wroclaw, Poland<EMAIL_ADDRESS>
**Modification technologies tested within the**

Performance of 120 selected façade materials provided by over 30 industrial and academic partners from 17 countries is under evaluation. The experimental samples were classified in seven categories, according to treatment applied: natural wood (or other bio-based materials), chemical modification, thermal modification, impregnations, coatings and/or surface treatments, composites, and hybrid modification, that include

> panels, bio-ceramics, tricoya, wood plastic composites different coatings, carbonized wood, nanocoatings

thermal treatment + coating, thermal treatment + impregnation,

DMDHEU, Knittex, Madurit, Fixapret vacuum, saturated steam, oil heat treatment

acetylation + coating etc.

**², Marta PETRILLO¹, Paolo GROSSI¹, Marcin BRZEZICKI³**

Accoya and Tricoya at the Accsys headquarters, Arnhem, The Netherlands

26

## **Performance of modified wood The BIO4ever project - how to convince**

**people to use bio-based building materials?**

#### **Anna SANDAK¹, Jakub SANDAK¹, ², Marta PETRILLO¹, Paolo GROSSI¹, Marcin BRZEZICKI³**

¹ CNR-IVALSA, via Biasi 75, San Michele all'Adige, Italy<EMAIL_ADDRESS><EMAIL_ADDRESS>petrillo@ivalsa. cnr.it<EMAIL_ADDRESS>
2 InnoRenew CoE, Livade 6, Izola, Slovenia<EMAIL_ADDRESS>
³ Wroclaw University of Science and Technology, ul. Prusa 53/55, Wroclaw, Poland<EMAIL_ADDRESS>
### **Introduction**

26

Accoya and Tricoya at the Accsys headquarters,

Arnhem, The Netherlands

Today's bio-based building materials, even if well characterized from the technical point of view, often lack reliable models describing performance during their service life. The overall goal of the BIO4ever project is to contribute to public awareness, by demonstrating the environmental benefits to be gained from the knowledge-based use of bio-based materials in buildings.

#### **Modification technologies tested within the BIO4ever project**

Performance of 120 selected façade materials provided by over 30 industrial and academic partners from 17 countries is under evaluation. The experimental samples were classified in seven categories, according to treatment applied: natural wood (or other bio-based materials), chemical modification, thermal modification, impregnations, coatings and/or surface treatments, composites, and hybrid modification, that include combination of at least two different treatments (Table 4).

*Table 5: Categories of bio-based facade materials tested within BIO4ever (Sandak et al. 2018)*

## **Performance of investigated samples**

All bio-materials are under extensive characterization before, during and after degradation by biotic and abiotic agents (natural weathering in San Michele, Italy, 46°11'15''N, 11°08'00''E), in order to provide experimental data to be used for better understanding the bio-materials performance/degradation as a function of time. The appearance change, being result of the progress of natural weathering is presented on Figure 18.

The experimental data, acquired during BIO4ever project duration are used for development of the numerical models simulating the material degradation in a function of time and exposure. The weather data calculated according to the ASHRAE 2013 database allows numerical simulation of cumulative radiation on building facades, situated in 6000 locations all over the world. Dedicated algorithms simulating material deterioration by taking into account specific material characteristics, kinetic and intensity of weathering process as well as specific architectonic details are extensively tested. The main project output is a software simulating biomaterials aesthetic performance integrated with LCA interactive calculation. The tool, dedicated for investors, architects, construction engineers, professional builders, suppliers and other relevant parties, including also final customers is now under validation and integration with the BIM software.

*Figure 18: The appearance change, being result of the progress of natural weathering. Appearance of investigated samples at a) the beginning of the test, and b) after 12 months of natural weathering at the southern exposure*

## **Acknowledgments**

The BIO4ever (RBSI14Y7Y4) is funded within a call SIR by MIUR. The authors gratefully acknowledge the European Commission for funding the InnoRenew CoE project (Grant Agreement #739574). Special acknowledgments to COST FP1303, COST FP1407 COST TU1403 for networking opportunity.

**BIO4ever project partners**: ABODO (New Zealand), Accsys Technologies (Netherlands), Bern University of Applied Sciences (Swizerland), BioComposites Centre (UK), CAMBOND (UK), Centre for Sustainable Products (UK), Drywood Coatings (Netherlands), EDUARD VAN LEER (Netherlands), FirmoLin (Netherlands), GraphiTech (Italy), Houthandel van Dam (Netherlands), ICA Group (Italy), IMOLA LEGNO (Italy), Kebony (Norway), KEVL SWM WOOD (Netherlands), Kul Bamboo (Germany), Latvian State Institute of Wood Chemistry (Latvia), Luleå Univ. of Technology (Sweden), NOVELTEAK (Costa Rica), Politecnico di Torino (Italy), RENNER ITALIA (Italy), Solas (Italy), SWM-Wood (Finland), Technological Institute FCBA (France), TIKKURILA (Poland), Univ. of Applied Science in Ferizaj (Kosovo), Univ. of Göttingen (Germany), Univ. of Life Science in Poznan (Poland), Univ. of Ljubljana (Slovenia), Univ. of West Hungary (Hungary), VIAVI (USA), WDE-Maspel (Italy).

29

**Conclusion and outlook**

Multi-family living is becoming the norm with the continued urbanisation of populations increasing the need for mid- to high-rise buildings, due to lack and cost of prime city land. With the growth in such buildings comes an increased need for higher performance in exterior products with greater importance placed on cost over life cycle, limited need for maintenance, homogenous and pleasing appearance, high durability and in many cases fire resistance. Many of these key requirements are extremely challenging for standard wood products to meet and thus there continues to be a growing contradiction between the impacts of global trends and the current technical capabilities of wood-based products. Other challenges such as increased constraints to use of efficient chemicals

for durability and protection are making the competitiveness of wood products even more challenged.

products in certain performance situations requires high levels of durability.

success for modified wood across Europe.

about all process related factors affecting the environment.

However, even in the face of these obstacles, considerable design innovation has taken place in recent years in the use of bio-based products in construction, with a number of international architects and engineers acting as enthusiastic trailblazers in the development of new building types and construction components and systems made principally from wood but and other naturally occurring materials. Most influential amongst these innovations to date has been the development of new engineered wood products together with the increasing emergence of economically viable wood modification processes, focussing on areas where the use of wood

Given this recognition, the use of modified wood continues to increase across Europe. In addition to the three main wood modification processes (acetylation, furfurylation, thermal modification), there has been a recent increase in the number of alternative processes being commercialised. In addition, there has been an expansion of the number of companies producing thermally modified wood, particularly for local use in a given country. The findings in the present study appear to show increased volumes to those estimated in 2015 (Militz 2015). One reason is that the European production levels has been further increased through the inclusion of an estimate of Russian production volumes, but considerable volumes are also under development for acetylation (UK) and furfurylation (Belgium). The demand for wood for exterior applications is increasing continuously. Here, terrace decking is the most important application, followed by façade cladding. Within the decking market, the share of wood-plastic composites (WPC) and natural fibre composites (NFC) has increased considerably (Scheiding 2018). Among the alternatives to preserved or tropical timber, acetylated and furfurylated timber has become more important. Furthermore, compressed and thermally modified bamboo products are to be found more frequently (when used for outdoor application, the bamboo is usually thermally modified). This continued demand for modified wood is despite the slow-down within the construction sector. This suggests that modified wood is gaining more favour with architects, specifiers and end-users as indicated earlier, which suggests a continued

Though many aspects of these treatments are known, the fundamental influence of the process on product performance, the environment, and end of life scenarios remain relatively unknown. It is essential to integrate interactive assessment of process parameters, developed product properties, and environmental impacts. To optimize modification processing to minimize environmental impacts, much more information must be gathered

# **Conclusion and outlook**

Multi-family living is becoming the norm with the continued urbanisation of populations increasing the need for mid- to high-rise buildings, due to lack and cost of prime city land. With the growth in such buildings comes an increased need for higher performance in exterior products with greater importance placed on cost over life cycle, limited need for maintenance, homogenous and pleasing appearance, high durability and in many cases fire resistance. Many of these key requirements are extremely challenging for standard wood products to meet and thus there continues to be a growing contradiction between the impacts of global trends and the current technical capabilities of wood-based products. Other challenges such as increased constraints to use of efficient chemicals for durability and protection are making the competitiveness of wood products even more challenged.

However, even in the face of these obstacles, considerable design innovation has taken place in recent years in the use of bio-based products in construction, with a number of international architects and engineers acting as enthusiastic trailblazers in the development of new building types and construction components and systems made principally from wood but and other naturally occurring materials. Most influential amongst these innovations to date has been the development of new engineered wood products together with the increasing emergence of economically viable wood modification processes, focussing on areas where the use of wood products in certain performance situations requires high levels of durability.

Given this recognition, the use of modified wood continues to increase across Europe. In addition to the three main wood modification processes (acetylation, furfurylation, thermal modification), there has been a recent increase in the number of alternative processes being commercialised. In addition, there has been an expansion of the number of companies producing thermally modified wood, particularly for local use in a given country. The findings in the present study appear to show increased volumes to those estimated in 2015 (Militz 2015). One reason is that the European production levels has been further increased through the inclusion of an estimate of Russian production volumes, but considerable volumes are also under development for acetylation (UK) and furfurylation (Belgium). The demand for wood for exterior applications is increasing continuously. Here, terrace decking is the most important application, followed by façade cladding. Within the decking market, the share of wood-plastic composites (WPC) and natural fibre composites (NFC) has increased considerably (Scheiding 2018). Among the alternatives to preserved or tropical timber, acetylated and furfurylated timber has become more important. Furthermore, compressed and thermally modified bamboo products are to be found more frequently (when used for outdoor application, the bamboo is usually thermally modified). This continued demand for modified wood is despite the slow-down within the construction sector. This suggests that modified wood is gaining more favour with architects, specifiers and end-users as indicated earlier, which suggests a continued success for modified wood across Europe.

Though many aspects of these treatments are known, the fundamental influence of the process on product performance, the environment, and end of life scenarios remain relatively unknown. It is essential to integrate interactive assessment of process parameters, developed product properties, and environmental impacts. To optimize modification processing to minimize environmental impacts, much more information must be gathered about all process related factors affecting the environment.

28

**Performance of investigated samples**

is now under validation and integration with the BIM software.

**a) b)**

**Acknowledgments**

*of the test, and b) after 12 months of natural weathering at the southern exposure*

COST FP1303, COST FP1407 COST TU1403 for networking opportunity.

(Slovenia), Univ. of West Hungary (Hungary), VIAVI (USA), WDE-Maspel (Italy).

All bio-materials are under extensive characterization before, during and after degradation by biotic and abiotic agents (natural weathering in San Michele, Italy, 46°11'15''N, 11°08'00''E), in order to provide experimental data to be used for better understanding the bio-materials performance/degradation as a function of time. The

The experimental data, acquired during BIO4ever project duration are used for development of the numerical models simulating the material degradation in a function of time and exposure. The weather data calculated according to the ASHRAE 2013 database allows numerical simulation of cumulative radiation on building facades, situated in 6000 locations all over the world. Dedicated algorithms simulating material deterioration by taking into account specific material characteristics, kinetic and intensity of weathering process as well as specific architectonic details are extensively tested. The main project output is a software simulating biomaterials aesthetic performance integrated with LCA interactive calculation. The tool, dedicated for investors, architects, construction engineers, professional builders, suppliers and other relevant parties, including also final customers

*Figure 18: The appearance change, being result of the progress of natural weathering. Appearance of investigated samples at a) the beginning*

The BIO4ever (RBSI14Y7Y4) is funded within a call SIR by MIUR. The authors gratefully acknowledge the European Commission for funding the InnoRenew CoE project (Grant Agreement #739574). Special acknowledgments to

**BIO4ever project partners**: ABODO (New Zealand), Accsys Technologies (Netherlands), Bern University of Applied Sciences (Swizerland), BioComposites Centre (UK), CAMBOND (UK), Centre for Sustainable Products (UK), Drywood Coatings (Netherlands), EDUARD VAN LEER (Netherlands), FirmoLin (Netherlands), GraphiTech (Italy), Houthandel van Dam (Netherlands), ICA Group (Italy), IMOLA LEGNO (Italy), Kebony (Norway), KEVL SWM WOOD (Netherlands), Kul Bamboo (Germany), Latvian State Institute of Wood Chemistry (Latvia), Luleå Univ. of Technology (Sweden), NOVELTEAK (Costa Rica), Politecnico di Torino (Italy), RENNER ITALIA (Italy), Solas (Italy), SWM-Wood (Finland), Technological Institute FCBA (France), TIKKURILA (Poland), Univ. of Applied Science in Ferizaj (Kosovo), Univ. of Göttingen (Germany), Univ. of Life Science in Poznan (Poland), Univ. of Ljubljana

appearance change, being result of the progress of natural weathering is presented on Figure 18.

Walkway of thermally modified Norway spruce, Grado, Italy

30

31

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A wooden church in the shape of a Sami goahti, a tent cot, painted with traditional "Swedish red coating". The architect was Gustav Wickman. The church was built between 1909-1912, and will be relocated as part of the ongoing city transformation; scheduled to be moved around 2025-2026

34 35

34 35

A wooden church in the shape of a Sami goahti, a tent cot, painted with traditional "Swedish red coating". The architect was Gustav Wickman. The church was built between 1909-1912, and will be relocated as part of the ongoing city transformation;

scheduled to be moved around 2025-2026

Oil treated Scots pine, Grythyttan Steel Furniture, Sweden

36

37

*1) Turkey is here counted as a European country, so 45 countries*

**Country information**

information is attached, and for the other countries are no information available.

**A M** Albania Malta Andorra Moldova **Austria** Monaco **B** Montenegro

Belarus **N**

**C P Croatia Poland Czech Republic Portugal**

**D R**

**Hungary T**

Iceland **U**

**L V**

Liechtenstein **Lithuania**

**I Turkey 1)**

**Ireland Ukraine**

Luxembourg *in total.*

**Italy United Kingdom**

**Latvia** Vatican City (Holy See)

**Denmark Romania E Russia Estonia S**

**F** San Marino **Finland Serbia France Slovakia G Slovenia Germany Spain Greece Sweden H Switzerland**

**Belgium Netherlands** Bosnia and Herzegovina **North Macedonia**

Bulgaria **Norway**

**about wood modification**

There are 441) countries in Europe 2019, according to the United Nations. Country names in **Bold** type, more

## **Country information about wood modification**

There are 441) countries in Europe 2019, according to the United Nations. Country names in **Bold** type, more information is attached, and for the other countries are no information available.

Dennis Jones, Dick Sandberg, Giacomo Goli, Luigi Todaro (edited by), *Wood Modification in Europe : a state-of-the-art about processes, products and applications*, © 2019 Author(s), content CC BY-SA 4.0 International, metadata CC0 1.0 Universal, published by Firenze University Press (www.fupress.com), ISSN 2704-5846 (online), ISBN 978-88-6453-970-6 (online PDF)

36

Oil treated Scots pine,

Grythyttan Steel Furniture, Sweden

The Moses Bridge in acetylated radiata pine, Fort De Roovere, Halsteren, The Netherlands

38

39

**Wood modification**

**Thomas SCHNABEL¹, Alfred TEISCHINGER², Dick SANDBERG³**

Engineering, Institute of Wood Science and Technology, Vienna/Tulln an der Donau, Austria

**A summary of wood modification activities**

2 BOKU – University of Natural Resources and Applied Life Sciences, Department of Material Sciences and Process

³Luleå University of Technology, Wood Science and Engineering, Skellefteå, Sweden; Czech University of Life Sciences

There are different applications for thermally modified wood produced in Austria. Thus thermally modified timber (TMT) occupies a special position. In Austria actually there exist four production sites for thermal modification with an estimated total annual production of about 15,000 m³ (2013). There also exist traditional

In Austria there was an increase in research and technology in wood modification in the years around 2000. Mitteramskogler (MIRAKO) was one of the leading companies, and BOKU had research projects, and the school in Kuchl/Salzburg had a "Competence Centre for Wood Modification" at that time (Teschinger & Stingl 2002). There was however never a real market break through - Mitteramskogler went bankrupt (today Heussermann) and the current volume of modified wood is very low. The main importance is in parquet flooring (Stia, Mafi) for colour management.

Today, frequently asked research questions are mainly related to the stabilization of the modified wood colour for different applications. There are primary two research institutes in Austria that deal with wood modification as needed, i) Department of Forest Products Technology & Timber Constructions at Salzburg University of Applied

Mirako is a sawmill and thermal modification plant in Gaflenz. In 2011, the Häussermann Group took over the business operations of Mirako GmbH. Häussermann, with its headquarters in Sulzbach/Murr (Baden-Württemberg),

Mirako has four chambers for thermal modification with a batch capacity of 10 m³ to 36 m³. Typical products are wooden flooring for bathrooms, frames for pools, balcony floors, noise barriers, musical instruments such as oboes and organ pipes, but also building system such as wooden facade system. Mirako follow the pre-standard

¹ Salzburg University of Applied Sciences, Campus Kuchl, Austria

wood bending (see biegeholz.com/ for examples of products), Table 6.

Sciences in Kuchl and ii) wood KPLUS in closely cooperation with BOKU in Tulln.

**in Austria**

<EMAIL_ADDRESS>
Prague (CULS), Prague, Czech Republic

<EMAIL_ADDRESS>
<EMAIL_ADDRESS>
founded in 1899.

ÖNORM CEN/TS 15679 for their TMT, Figure 19.

## **Wood modification in Austria**

#### **Thomas SCHNABEL¹, Alfred TEISCHINGER², Dick SANDBERG³**

¹ Salzburg University of Applied Sciences, Campus Kuchl, Austria<EMAIL_ADDRESS>
2 BOKU – University of Natural Resources and Applied Life Sciences, Department of Material Sciences and Process Engineering, Institute of Wood Science and Technology, Vienna/Tulln an der Donau, Austria<EMAIL_ADDRESS>
³Luleå University of Technology, Wood Science and Engineering, Skellefteå, Sweden; Czech University of Life Sciences Prague (CULS), Prague, Czech Republic

<EMAIL_ADDRESS>
The Moses Bridge in acetylated radiata pine, Fort De Roovere, Halsteren, The Netherlands

38

## **A summary of wood modification activities**

There are different applications for thermally modified wood produced in Austria. Thus thermally modified timber (TMT) occupies a special position. In Austria actually there exist four production sites for thermal modification with an estimated total annual production of about 15,000 m³ (2013). There also exist traditional wood bending (see biegeholz.com/ for examples of products), Table 6.

In Austria there was an increase in research and technology in wood modification in the years around 2000. Mitteramskogler (MIRAKO) was one of the leading companies, and BOKU had research projects, and the school in Kuchl/Salzburg had a "Competence Centre for Wood Modification" at that time (Teschinger & Stingl 2002). There was however never a real market break through - Mitteramskogler went bankrupt (today Heussermann) and the current volume of modified wood is very low. The main importance is in parquet flooring (Stia, Mafi) for colour management.

Today, frequently asked research questions are mainly related to the stabilization of the modified wood colour for different applications. There are primary two research institutes in Austria that deal with wood modification as needed, i) Department of Forest Products Technology & Timber Constructions at Salzburg University of Applied Sciences in Kuchl and ii) wood KPLUS in closely cooperation with BOKU in Tulln.

Mirako is a sawmill and thermal modification plant in Gaflenz. In 2011, the Häussermann Group took over the business operations of Mirako GmbH. Häussermann, with its headquarters in Sulzbach/Murr (Baden-Württemberg), founded in 1899.

Mirako has four chambers for thermal modification with a batch capacity of 10 m³ to 36 m³. Typical products are wooden flooring for bathrooms, frames for pools, balcony floors, noise barriers, musical instruments such as oboes and organ pipes, but also building system such as wooden facade system. Mirako follow the pre-standard ÖNORM CEN/TS 15679 for their TMT, Figure 19.

*Table 6: Wood modification in Austria (Thermal modification from Holzkurier - Reitberger 2013)*

\* Stift Admont Holzindustrie

Mafi is a flooring manufacturer and their flooring is exclusively produced in Austria - from the tree to the flooring. They operate two plants for their production; Steindorf processes the tree up to the slats, and in Schneegattern the slats are then processed into floorings, Figure 19.

Stia is a flooring manufacturer. The Admonter Mocca represents a product range of flooring which includes dark colours achieved by thermal modification. By regulating the temperature and the duration of the heat, different colour shades can be achieved. TMT also allows the manufacture of Mocca flooring suitable for rooms with a higher humidity and for under-heated floors.

*Figure 19: An example of thermally modified timber in Austria*

BRAUN Lockenhaus focuses on the manufacturing of seating furniture made of solid wood, bentwood, decorated wood laminate and tubular steel. BRAUN Lockenhaus is one of a very few companies in Austria being expert in the area of the old craft of bending wood. Since 2005, BRAUN Lockenhaus is a subsidiary of the German Hiller group, known today as Schneeweiss AG Interior. The enterprise is a market leader in the production of tables and seating solutions made of wood, tubular steel, stainless steel and plastic at European level, Figure 20.

41

*Figure 20: Bentwood products from BRAUN Lockenhaus: CO03 chairbed (left) and the more traditional M99 chair (right). The furniture's*

Teschinger A, Stingl R (2002). *Modifiziertes Holz: Eigenschaften und Märkte.* Lignovisionen Band 3. Universität für

*are designed by Adolf Krischanitz*

Bodenkultur, BOKU.

**Reference**

*Figure 20: Bentwood products from BRAUN Lockenhaus: CO03 chairbed (left) and the more traditional M99 chair (right). The furniture's are designed by Adolf Krischanitz*

#### **Reference**

40

*Table 6: Wood modification in Austria (Thermal modification from Holzkurier - Reitberger 2013)*

MIRAKO ThermoHolz 7,500 m³ 10,000 m³ Deliver TMT,

Stia\* Admonter

\* Stift Admont Holzindustrie

SCHNEEWEISS

AG

Mocca

BRAUN Lockenhaus

slats are then processed into floorings, Figure 19.

higher humidity and for under-heated floors.

*Figure 19: An example of thermally modified timber in Austria*

**Company Trademark Production Capacity Products Process Webpage**

decking

No data No data Flooring No info. www.admonter.eu/

bending,veneer moulding

Mafi Vulcano 6,000 m³ No data Flooring No info. https://mafi.com/en/action/

Aberger Thermoholz 1,400 m³ 1,400 m³ Decking No info. www.thermoholz-aberger.at/

Mafi is a flooring manufacturer and their flooring is exclusively produced in Austria - from the tree to the flooring. They operate two plants for their production; Steindorf processes the tree up to the slats, and in Schneegattern the

Stia is a flooring manufacturer. The Admonter Mocca represents a product range of flooring which includes dark colours achieved by thermal modification. By regulating the temperature and the duration of the heat, different colour shades can be achieved. TMT also allows the manufacture of Mocca flooring suitable for rooms with a

BRAUN Lockenhaus focuses on the manufacturing of seating furniture made of solid wood, bentwood, decorated wood laminate and tubular steel. BRAUN Lockenhaus is one of a very few companies in Austria being expert in the area of the old craft of bending wood. Since 2005, BRAUN Lockenhaus is a subsidiary of the German Hiller group, known today as Schneeweiss AG Interior. The enterprise is a market leader in the production of tables and seating

solutions made of wood, tubular steel, stainless steel and plastic at European level, Figure 20.

No info. www.mirako.at

www.haeussermann.de

https://www.braunlockenhaus.

Vulcano\_s12930

at/en/company/

Teschinger A, Stingl R (2002). *Modifiziertes Holz: Eigenschaften und Märkte.* Lignovisionen Band 3. Universität für Bodenkultur, BOKU.

Wood surface densification of Scots pine, Sweden

42

43

**Annual volumes produced and companies involved in the process**

Estimated capactity 20,000 m³

Estimated production 1,500 m³

**Wood modification**

¹UGent – Ghent University, Laboratory of Wood Technology (Woodlab), Coupure links 653, 9000 Ghent, Belgium

Wood modification has for several decades been important in Belgium and this was underlined by the

organization of the first European Wood Modification Conference in Ghent in 2003 by the European Thematic Network for Wood Modification. The presence of several production plants in The Netherlands definitely delayed the start of specific production sites in Belgium. Today we still see this is an ongoing process and both the use of tropical wood species and the presence of international harbours like Antwerp seem to be drivers in this respect.

There seems to be similarities in the approach in The Netherlands and developments in Flanders, the northern part of Belgium. Both have low forest cover and depend largely on import of timber and forest products. Import of tropical timbers is significant and there is tradition of trading forest products. Open border systems existing since the introduction of the BeNeLux in 1958 allowed since long to transfer raw materials up to finished products between The Netherlands and Belgium. Today we can observe a clear presence of modified wood from The Netherlands on the Belgian market, but we also observe that specific companies provide treating products in opposite direction. Additionally also products from the main countries involved in producing modified timber are present on the Belgian market and competing for specific markets related several commodities and applications,

**Modification technologies and production volumes**

Besides the producers of thermally modified wood LDCwood (joint venture of the timber importing companies Lemahieu en Decolvenaere) and Debeuckelaere there are also some companies active in promoting and interacting on the Belgian market with specific products based on production sites in other countries. The company SWP (Stockmans Wood Products - http://www.swp-timber.com) is commercializing ThermoDUR products, which are linked to Smartheat products (https://www.lignius.nl/, the Netherlands). The company Carpentier (http://www.carpentier.be)

Actually at this moment there are only a few companies producing modified wood in Belgium. As you can see from Table 7 only thermal wood modification is present and relates primarily to modification of (tropical)

*Table 7: Wood modification technologies, producers, companies and production volumes in Belgium*

**technology Producer, process short description and website**

https://ldcwood.com/en/

Thermo VacWood Debeuckelaere Gebroeders nv ThermoVuoto process http://www.debeuckelaere.com/

**in Belgium**

**Joris VAN ACKER¹, Lieven DE BOEVER²**

2Wood.be, Hof ter Vleestdreef 3, 1070 Brussels, Belgium

mainly cladding and decking but also for exterior joinery.

hardwoods alongside common softwood species.

ThermoWood LDCwood ThermoWood process

**Wood modification**

Joris.VanAcker@UGent

**Introduction**

<EMAIL_ADDRESS>
## **Wood modification in Belgium**

#### **Joris VAN ACKER¹, Lieven DE BOEVER²**

¹UGent – Ghent University, Laboratory of Wood Technology (Woodlab), Coupure links 653, 9000 Ghent, Belgium Joris.VanAcker@UGent

2Wood.be, Hof ter Vleestdreef 3, 1070 Brussels, Belgium<EMAIL_ADDRESS>
## **Introduction**

42

Sweden

Wood surface densification of Scots pine,

Wood modification has for several decades been important in Belgium and this was underlined by the organization of the first European Wood Modification Conference in Ghent in 2003 by the European Thematic Network for Wood Modification. The presence of several production plants in The Netherlands definitely delayed the start of specific production sites in Belgium. Today we still see this is an ongoing process and both the use of tropical wood species and the presence of international harbours like Antwerp seem to be drivers in this respect.

There seems to be similarities in the approach in The Netherlands and developments in Flanders, the northern part of Belgium. Both have low forest cover and depend largely on import of timber and forest products. Import of tropical timbers is significant and there is tradition of trading forest products. Open border systems existing since the introduction of the BeNeLux in 1958 allowed since long to transfer raw materials up to finished products between The Netherlands and Belgium. Today we can observe a clear presence of modified wood from The Netherlands on the Belgian market, but we also observe that specific companies provide treating products in opposite direction. Additionally also products from the main countries involved in producing modified timber are present on the Belgian market and competing for specific markets related several commodities and applications, mainly cladding and decking but also for exterior joinery.

## **Modification technologies and production volumes**

Actually at this moment there are only a few companies producing modified wood in Belgium. As you can see from Table 7 only thermal wood modification is present and relates primarily to modification of (tropical) hardwoods alongside common softwood species.

*Table 7: Wood modification technologies, producers, companies and production volumes in Belgium*

Besides the producers of thermally modified wood LDCwood (joint venture of the timber importing companies Lemahieu en Decolvenaere) and Debeuckelaere there are also some companies active in promoting and interacting on the Belgian market with specific products based on production sites in other countries. The company SWP (Stockmans Wood Products - http://www.swp-timber.com) is commercializing ThermoDUR products, which are linked to Smartheat products (https://www.lignius.nl/, the Netherlands). The company Carpentier (http://www.carpentier.be) sells amongst others HOTwood ash. Often focus is on decking and cladding but also window frames (e.g. so-called TMT Fraké based on *Terminalia superba*), insulating wood materials (e.g. products based on low density hardwoods like Thermo Ayous, *Triplochiton scleroxylon*) and other high end products often originating from specific treating facilities that are using vacuum plate systems as part of the process.

Besides TMT (Thermally Modified Timber) there is also scope for chemically modified wood. Accoya products from the Accsys acetylation plant in Arnhem, The Netherlands (https://www.accoya.com/) are since long present on the Belgian market and available from the distributor company Hout van Steenberge nv (https:// www.vansteenberge.be) that also is selling the Medite Tricoya wood based panel. Originating mainly from The Netherlands modern window frames based on finger-jointed laminated beams are not only using thermally modified wood species often in combination with spruce, but also acetylated radiate pine is used in combination with Scots pine (www.ibrid.nl).

The company TFC (Transfurans Chemicals - https://www.polyfurfurylalcohol.com/building-construction) is a main producer of furfuryl alcohol used for the chemical modification called furfurylation and also producer of the Biorez resin used for treatment of the Nobelwood products by Foreco in The Netherlands (http://www.foreco.nl/ nobelwood.html). The construction of a new production plant for furfurylated wood was started in 2017 by Kebony Belgium (https://kebony.com/sv/blog/second-factory-belgium/) as a second factory envisaging an initial capacity of 20,000 m³ with potential to increase to 40,000 m³.

Alongside thermal and chemical wood modification, there has been an interest in hydrophobation of wood with organosilicon compounds since beginning this century by the company Dow Construction Chemicals having their research facilities in Seneffe, Belgium. They just finished successfully an EU Life+ project SILEX showing the potential of some of their formulations.

This is a compilation of info available beginning 2018 for Belgium and it is expected that additional wood modification plants will be functional later that year and the coming years especially when considering all innovative technologies being introduced as indicated by Sandberg *et al*. (2017) and linked to the impact of high ranked publication(s) appearing recently (Song *et al*. 2018).

#### **References**

Sandberg D, Kutnar A, Mantanis G (2017). Wood modification technologies - a review. *iForest Biogeosciences and Forestry* 10, 895-908

Song J, Chen C, Zhu S, Zhu M, Dai J, Ray U, Li Y, Kuang Y, Li Y, Quispe N, Yao Y, Gong A, Leiste UH, Bruck HA, Zhu JY, Vellore A, Li H, Minus ML, Jia Z, Martini A, Li T, Hu L (2018). Processing bulk natural wood into a highperformance structural material. *Nature* 554, 224-228

45

cladding, decking and interior floorings

**Wood modification**

and chemical modification via the use of compounds such as citric acid.

**technology Producer, process short description and website Products**

Thermal modification PPS Galeković. Treatments in water vapour atmosphere. https://pps-galekovic.hr/en/

**Wood Modification in Croatia**

*Table 8: Summary of companies producing modified wood in Croatia*

undertaking small-scale production (Table 8).

University of Zagreb, Wood Technology Section, Trg maršala Tita 14, HR-10000, Zagreb, Grad Zagreb, Croatia

In Croatia, forests and forest land cover 46% of total land area which amounts to 56,594 km2 and makes Croatia one of the countries with the highest forest cover in Europe. State forests account for 80% of the total forest area in the country, whilst the privately-owned forests are often small individual areas of land (under 1 ha.). The amount of forests and forest land per inhabitant is 6,000 m2. The main species present are beech and oak (common and durmast), common hornbeam, and combined fir/spruce. The desire to use local materials has helped define a wood modification programme at the University of Zagreb, particularly with thermal modification

Currently, the majority of modified wood used in Croatia is imported from the major manufacturers, such as ThermoWood. However, there is growing interest to locally produce modified wood, with two companies to date

Thermal modification Evolen d.o.o. http://evolen.hr cladding, decking and interior floorings

As architects learn more about the properties of modified wood, its use in new projects will increase.

**in Croatia**

**Vjekoslav ŽIVKOVIĆ**

**Introduction**

<EMAIL_ADDRESS>
**Wood modification**

## **Wood modification in Croatia**

#### **Vjekoslav ŽIVKOVIĆ**

University of Zagreb, Wood Technology Section, Trg maršala Tita 14, HR-10000, Zagreb, Grad Zagreb, Croatia<EMAIL_ADDRESS>
## **Introduction**

44

sells amongst others HOTwood ash. Often focus is on decking and cladding but also window frames (e.g. so-called TMT Fraké based on *Terminalia superba*), insulating wood materials (e.g. products based on low density hardwoods like Thermo Ayous, *Triplochiton scleroxylon*) and other high end products often originating from specific treating

Besides TMT (Thermally Modified Timber) there is also scope for chemically modified wood. Accoya products from the Accsys acetylation plant in Arnhem, The Netherlands (https://www.accoya.com/) are since long present on the Belgian market and available from the distributor company Hout van Steenberge nv (https:// www.vansteenberge.be) that also is selling the Medite Tricoya wood based panel. Originating mainly from The Netherlands modern window frames based on finger-jointed laminated beams are not only using thermally modified wood species often in combination with spruce, but also acetylated radiate pine is used in combination

The company TFC (Transfurans Chemicals - https://www.polyfurfurylalcohol.com/building-construction) is a main producer of furfuryl alcohol used for the chemical modification called furfurylation and also producer of the Biorez resin used for treatment of the Nobelwood products by Foreco in The Netherlands (http://www.foreco.nl/ nobelwood.html). The construction of a new production plant for furfurylated wood was started in 2017 by Kebony Belgium (https://kebony.com/sv/blog/second-factory-belgium/) as a second factory envisaging an initial capacity

Alongside thermal and chemical wood modification, there has been an interest in hydrophobation of wood with organosilicon compounds since beginning this century by the company Dow Construction Chemicals having their research facilities in Seneffe, Belgium. They just finished successfully an EU Life+ project SILEX showing the

This is a compilation of info available beginning 2018 for Belgium and it is expected that additional wood modification plants will be functional later that year and the coming years especially when considering all innovative technologies being introduced as indicated by Sandberg *et al*. (2017) and linked to the impact of high

Sandberg D, Kutnar A, Mantanis G (2017). Wood modification technologies - a review. *iForest Biogeosciences and*

Song J, Chen C, Zhu S, Zhu M, Dai J, Ray U, Li Y, Kuang Y, Li Y, Quispe N, Yao Y, Gong A, Leiste UH, Bruck HA, Zhu JY, Vellore A, Li H, Minus ML, Jia Z, Martini A, Li T, Hu L (2018). Processing bulk natural wood into a high-

facilities that are using vacuum plate systems as part of the process.

with Scots pine (www.ibrid.nl).

of 20,000 m³ with potential to increase to 40,000 m³.

ranked publication(s) appearing recently (Song *et al*. 2018).

performance structural material. *Nature* 554, 224-228

potential of some of their formulations.

**References**

*Forestry* 10, 895-908

In Croatia, forests and forest land cover 46% of total land area which amounts to 56,594 km2 and makes Croatia one of the countries with the highest forest cover in Europe. State forests account for 80% of the total forest area in the country, whilst the privately-owned forests are often small individual areas of land (under 1 ha.). The amount of forests and forest land per inhabitant is 6,000 m2. The main species present are beech and oak (common and durmast), common hornbeam, and combined fir/spruce. The desire to use local materials has helped define a wood modification programme at the University of Zagreb, particularly with thermal modification and chemical modification via the use of compounds such as citric acid.

## **Wood Modification in Croatia**

Currently, the majority of modified wood used in Croatia is imported from the major manufacturers, such as ThermoWood. However, there is growing interest to locally produce modified wood, with two companies to date undertaking small-scale production (Table 8).

*Table 8: Summary of companies producing modified wood in Croatia*

As architects learn more about the properties of modified wood, its use in new projects will increase.

Exterior cladding of Norway spruce coated with nano-technology based wax. Kamppi Chapel, Helsinki, Finland

46

47

**Annual volumes produced and companies involved in the process**

No wood modification production

Not available

Not available

**Wood modification**

**A summary of wood modification activities**

The veneer producer Danzer also apply different methods for staining and modification of veneer.

staining processes; high-frequency based bending

producer of thermal modification kilns - ThermoWood

Danzer Bohemia-Dýhárna employs more than 600 people at the sites Křivenice near Mělník and Frýdlant near Raspenava. (https://www.danzer.cz/cz/)

chambers for thermal modification according to the ThermoWood process (Table 9).

*Table 9: Wood modification technologies, producers, companies and production volumes*

**technology Producer, process short description and website**

Wood bending TON produce furniture by steaming, bending and

Thermal modification kilns KATRES spol. s.r.o. (Katres drying technology) is a

(www.katres.cz/)

process (www.ton.eu/en/)

CULS – Czech University of Life Sciences Prague, Department of Forestry and Biomaterials, 16500 Prague, Suchdol, Czech Republic

Wood modification production is rare in the Czech Republic. Since 1861, solid wood bending has been applied for furniture production by the former Michael Thonét owned factory TON in Bystřice pod Hostýnem. The principles of bending wood were adopted by TON in 1953 after several changes of property rights and company names. The factory in Bystřice pod Hostýnem is the oldest in the world where this manufacturing technology is still used, Figure 21. The most frequently processed wood is beech as it has the best characteristic features for wood bending. Although TON has implemented modern machinery to the manufacturing process, some operations are still done

Other than the above mentioned modification processes, there are no other types of wood modification processes applied in the Czech Republic, but there also exists one producer of thermal modification kilns. Katres drying technology (KATRES spol. s.r.o.) is a Czech producer of drying equipment for sawmills that also produces and sell

**in Czech Republic**

**Milan GAFF, Dick SANDBERG**

manually and are unlikely to be substituted by machinery.

<EMAIL_ADDRESS>
**Wood modification**

Densification and moodification of veneer

## **Wood modification in Czech Republic**

#### **Milan GAFF, Dick SANDBERG**

46

Kamppi Chapel, Helsinki, Finland

Exterior cladding of Norway spruce coated with nano-technology based wax.

CULS – Czech University of Life Sciences Prague, Department of Forestry and Biomaterials, 16500 Prague, Suchdol, Czech Republic<EMAIL_ADDRESS>
## **A summary of wood modification activities**

Wood modification production is rare in the Czech Republic. Since 1861, solid wood bending has been applied for furniture production by the former Michael Thonét owned factory TON in Bystřice pod Hostýnem. The principles of bending wood were adopted by TON in 1953 after several changes of property rights and company names. The factory in Bystřice pod Hostýnem is the oldest in the world where this manufacturing technology is still used, Figure 21. The most frequently processed wood is beech as it has the best characteristic features for wood bending. Although TON has implemented modern machinery to the manufacturing process, some operations are still done manually and are unlikely to be substituted by machinery.

The veneer producer Danzer also apply different methods for staining and modification of veneer.

Other than the above mentioned modification processes, there are no other types of wood modification processes applied in the Czech Republic, but there also exists one producer of thermal modification kilns. Katres drying technology (KATRES spol. s.r.o.) is a Czech producer of drying equipment for sawmills that also produces and sell chambers for thermal modification according to the ThermoWood process (Table 9).

*Table 9: Wood modification technologies, producers, companies and production volumes*

*Figure 21: Wood bending of furniture components at the TON company, and examples of the Thonét chairs*

49

**Annual volumes produced and companies involved in the process**

Not available

Not available

**Wood modification**

**A summary of wood modification activities**

The majority of research into wood modification in Denmark has to date focussed on the treatment of wood fibres. The majority of this research has been conducted on enzyme modification, particularly on the use of laccase to increase the cross-linking of lignin (Felby *et al.* 2002), though the treatment concept was applied to solid wood (Felby & Hansen 2000). Much of this work was undertaken within the BioMat project in Denamrk, at the same time as studies into the hygrothermal treatment of wood and plant fibres (Hoffmeyer *et al*. 2003). Besides that no

**Modification technologies and production volumes**

There were previous attempts to undertake semi-commercial acetylation of wood fibres, with plans announced at the Fourth European Conference on Wood Modification in 2009 by DanAcell Denmark A/S (Jones et al. 2009).

However, attempts to generate sufficient financial backing failed to achieve commercial development.

Celloc undertakes thermal modification procedures using its own kilns for local markets and merchants. ThermoTreat 2.0 is a process and technology patented by Wood Treatment Technology. ThermoTreat 2.0 is approved by the Nordic Wood Preservation Council as first non-biocide containing treatment process ever. The

process utilizes a closed autoclave system with inert gas heating. The process time less than 10 hours.

wood for clients in two own produced kilns

modified siding and decking boards. The finished products are treated with Royal (linseed-based) hot oil.

In addition, wood from different commercialised modification processes (e.g. ThermoWood, Kebony, Accoya,

Currently there are two companies producing thermally modified timber (Table 10).

*Table 10: Wood modification technologies, producers, companies and production volumes*

**technology Producer, process short description and website**

Thermal modification Celloc (www.celloc.dk) does thermal modification of

ThermoTreat 2.0 Sagawood (www.sagawood.dk) produces thermally

Organowood) are imported directly into Denmark for use.

**in Denmark**

WTT A/S, Jyllandsvej 9, 7330 Brande, Denmark

academic community really on this topic.

**Wood modification**

**Thomas Mark VENÅS**

<EMAIL_ADDRESS>
## **Wood modification in Denmark**

#### **Thomas Mark VENÅS**

48

*Figure 21: Wood bending of furniture components at the TON company, and examples of the Thonét chairs*

WTT A/S, Jyllandsvej 9, 7330 Brande, Denmark<EMAIL_ADDRESS>
## **A summary of wood modification activities**

The majority of research into wood modification in Denmark has to date focussed on the treatment of wood fibres. The majority of this research has been conducted on enzyme modification, particularly on the use of laccase to increase the cross-linking of lignin (Felby *et al.* 2002), though the treatment concept was applied to solid wood (Felby & Hansen 2000). Much of this work was undertaken within the BioMat project in Denamrk, at the same time as studies into the hygrothermal treatment of wood and plant fibres (Hoffmeyer *et al*. 2003). Besides that no academic community really on this topic.

## **Modification technologies and production volumes**

There were previous attempts to undertake semi-commercial acetylation of wood fibres, with plans announced at the Fourth European Conference on Wood Modification in 2009 by DanAcell Denmark A/S (Jones et al. 2009). However, attempts to generate sufficient financial backing failed to achieve commercial development.

Currently there are two companies producing thermally modified timber (Table 10).

Celloc undertakes thermal modification procedures using its own kilns for local markets and merchants. ThermoTreat 2.0 is a process and technology patented by Wood Treatment Technology. ThermoTreat 2.0 is approved by the Nordic Wood Preservation Council as first non-biocide containing treatment process ever. The process utilizes a closed autoclave system with inert gas heating. The process time less than 10 hours.

*Table 10: Wood modification technologies, producers, companies and production volumes*

In addition, wood from different commercialised modification processes (e.g. ThermoWood, Kebony, Accoya, Organowood) are imported directly into Denmark for use.

### **References**

51

**Wood modification**

2Tallinn University of Technology, Teaduspargi 5, Tallinn, 12618 Harjumaa<EMAIL_ADDRESS>
According to the national statistics of 2016, the direct added value arising from the forest and wood sector for Estonia was 5.3% of the total GDP. Of this, the percentage of wood, paper, and furniture industry in manufacturing industry was 35%, with the revenues from sales totalling € 3.3 billion. Timber products have always been an important export commodity for Estonia over the centuries. Today, exports from Estonian timber companies consist of a wide range of different product groups as sawn and planed timber, pre-fabricated structural details for construction and for furniture manufacturers, or element and modular buildings. During the last decade, there has been a substantial

**Modification technologies and production volumes**

**Wood modification product Year 2016 Unit** Sawn timber 2,183,000 m³ Glulam and CLT 359,600 m³ Wood pellet 1,166,514 ton Thermo-mechanical pulp 172,900 ton Unbleached paper 65,300 ton Plywood 55,700 m³ Veneer 108,400 m³ Chipboard 120,000 m³ Fibreboard 7,123,800 m²

increase in the number of products with higher added value included in these exports (EMPL 2017).

Current wood production volumes by categories are shown in the Table 11 (EMPL 2017).

**in Estonia**

Tartu, 51014 Tartumaa, Estonia<EMAIL_ADDRESS>
Tallinn 10412 Harjumaa, Estonia

**Introduction**

*Table 11: Wood production volumes (total) in Estonia 2016*

Main producers of wood modified products are shown in Table 12.

<EMAIL_ADDRESS>
**Tõnis TEPPAND¹, Jaan KERS², Liisi LIIVLAID³** ¹Estonian University of Life Sciences, Fr.R. Kreutzwaldi 5-1C7,

³EMPL – Woodworking Industry Development Cluster, Telliskivi 60,

## **Wood modification in Estonia**

#### **Tõnis TEPPAND¹, Jaan KERS², Liisi LIIVLAID³**

¹Estonian University of Life Sciences, Fr.R. Kreutzwaldi 5-1C7, Tartu, 51014 Tartumaa, Estonia<EMAIL_ADDRESS>
2Tallinn University of Technology, Teaduspargi 5, Tallinn, 12618 Harjumaa<EMAIL_ADDRESS>³EMPL – Woodworking Industry Development Cluster, Telliskivi 60, Tallinn 10412 Harjumaa, Estonia

<EMAIL_ADDRESS>
## **Introduction**

According to the national statistics of 2016, the direct added value arising from the forest and wood sector for Estonia was 5.3% of the total GDP. Of this, the percentage of wood, paper, and furniture industry in manufacturing industry was 35%, with the revenues from sales totalling € 3.3 billion. Timber products have always been an important export commodity for Estonia over the centuries. Today, exports from Estonian timber companies consist of a wide range of different product groups as sawn and planed timber, pre-fabricated structural details for construction and for furniture manufacturers, or element and modular buildings. During the last decade, there has been a substantial increase in the number of products with higher added value included in these exports (EMPL 2017).

### **Modification technologies and production volumes**

Current wood production volumes by categories are shown in the Table 11 (EMPL 2017).

*Table 11: Wood production volumes (total) in Estonia 2016*

Main producers of wood modified products are shown in Table 12.

50

**References**

US6045865A.

Felby C, Hansen TT (2000). *Process for impregnating solid wood and product obtainable by the process.* US Patent

fibres. In: *Proc. 1st European Conference on Wood Modification*, Ghent, Belgium, 177-189.

*Proc. 4th European Conference on Wood Modification*, Cardiff UK, 505-513.

Felby C, Hassingboe J, Lund M (2002). Pilot-scale production of fiberboards made by laccase oxidized wood fibers: board properties and evidence for cross-linking of lignin. *Enzyme and Microbial Technology* 31(6), 736-741. Hoffmeyer P, Jensen SK, Jones D, Klinke HC, Felby C (2003). Sorption properties of steam treated wood and plant

Jones D, Lawther M, Torgilson R, Simonson R (2009). Acetylated wood fibres – Next stop: Commercialisation. In:

**Practical examples**

*Figure 22: Example of Thermory cladding in Estonia*

EjLFKIUfAK6ByynCg7ori8xAq-7b8

http://haserv.ee/en/company/thermo-treatment/

**References**

The Winner of Wooden Buildings 2016 in Estonia was Arcwood`s new office and industrial building, made of their own produced CLT (walls, ceilings, stairs, commercial stend etc.) and GL details (columns, beams, railings). The

http://thermory.com/en/thermory-and-ha-serv-have-merged/?fbclid=IwAR2ESQNBBMLl1pBM03Vhu8oygKCPRA

http://hdgbuildingmaterials.com/wp-content/uploads/2017/01/Thermory-Brand-Presentation-copy.pdf

use of Thermory (Figure 22) is increasing in popularity with architects and specifiers.

Recently, Thermory and Ha Serv merged to become the largest producer of thermally modified wood and Sauna materials in Europe, with unconfirmed production volumes of 19,000 m³/year.

53

## **Practical examples**

The Winner of Wooden Buildings 2016 in Estonia was Arcwood`s new office and industrial building, made of their own produced CLT (walls, ceilings, stairs, commercial stend etc.) and GL details (columns, beams, railings). The use of Thermory (Figure 22) is increasing in popularity with architects and specifiers.

*Figure 22: Example of Thermory cladding in Estonia*

#### **References**

52

*Table 12: Wood modification technologies, main producers, companies and production volumes in Estonia*

http://www.arcwood.ee/en

profile. Length up to 6 m.

http://www.barrus.ee/en/

http://www.tapamill.ee/

Treatment Lotus Timber OÜ. Deep-impregnated wooden poles, fire

Pressure treated timber Imprest AS. Machine rounded timber products, outdoor

Hot oil treatment Hansacom OÜ. Deep impregnation of timber (Koppers). http://www.hansacom.ee/en/

protection. http://www.lotustimber.ee/en

playgrounds, preservative - treated wood. http://www.imprest.ee/EN/company/introduction/

Timber strips, colouring Trives OÜ. Production of strips and components made of softwood,

http://www.combiwood.ee/en/node/9

Kohila Vineer OÜ. Production of birch veneer and plywood. http://

plywood for construction, furniture and transport industries. http://www.wisaplywood.com/Contacts/production- units/otepaa/

Tarmeko Spoon AS. Production of rotary cut birch veneer. http://tarmeko.ee/companies/veneer/production

veneer and formatted veneer of various thicknesses.

Valmos OÜ. Rotary cut veneer and sliced veneer, but also plywood

Recently, Thermory and Ha Serv merged to become the largest producer of thermally modified wood and Sauna

Timber strips, colouring Combiwood OÜ. Wooden mouldings finished with primer and

Veneer, plywood UPM-Kymmene Otepää AS. Uncoated and coated WISA birch

Barrus AS.

Tapa Mill OÜ.

coloring.

http://trives.ee/en/

surface paint.

kohilavineer.ee/

Pages/Default.aspx

http://www.valmos.ee/en/

Stora Enso Eesti AS (Imavere, Näpi). http://www.storaenso.com

materials in Europe, with unconfirmed production volumes of 19,000 m³/year.

**technology Producer, process short description and website Annual volume production**

CLT: max measurements 3.5x15 m, thickness of panels 60-300 mm.

Lemeks AS (Pinest AS). GL components glued into blocks, L and T

http://www.pinest.ee/en/you-have-discovered- pinest-welcome.html

60,000 m³ (80% export)

(95% export)

45,000 m³

90,000 m³

10,000 m³

Peetri Puit OÜ. GL: length 1.0-29.5 m, max height 2.3 m.

**Wood modification**

Finger jointed timber, GL components

Finger jointed timber,

Vacuum-pressing treatment, finger-jointed

GL pine

timber

Birch veneer, plywood

Birch veneer, plywood

plywood

Veneer (mainly birch),

GL components of timber, planned timber products

GL, GL-panels, finger-jointed structural timber, DUO-TRIO, CLT

> http://thermory.com/en/thermory-and-ha-serv-have-merged/?fbclid=IwAR2ESQNBBMLl1pBM03Vhu8oygKCPRA EjLFKIUfAK6ByynCg7ori8xAq-7b8

http://hdgbuildingmaterials.com/wp-content/uploads/2017/01/Thermory-Brand-Presentation-copy.pdf

http://haserv.ee/en/company/thermo-treatment/

Wine barrels, Iasi, Romania

54

55

**Wood modification**

Information in this report is based either on personal communications between the author and company representatives or websites of the companies. Prognosis regarding the ThermoWood® production in 2018 is a

The ThermoWood® process (www.thermowood.fi) was developed in Finland in the 1990s. Nowadays the International

In addition to the registered ThermoWood producers, there is one company (www.rakennuspuu.fi/en) producing

approximately 2,000 m³ thermally modified timber per year, but it does not belong to the International

Thus, the total production of thermally modified wood in Finland was approximately 172,000 m³ in 2017.

The following points present other modified wood products commercialized in Finland. All products are rather

• Kivipuu (trademark Siligna® in German speaking markets, and Silica® in French speaking markets) silica impregnated wood, a joint effort of Lapuan Saha Ltd., Aureskoski Ltd., and Tammiston Puu Ltd. Product launched into markets in 2018. Maintenance free product, fire retardancy class Bs1d0. Estimated product sales approximately 1,000 m³ for 2018, production capacity approximately 20,000 m³/a. (http://aureskoski.fi/wp-

• Waurum, a brand for modified wood produced by Paattimaakarit Ltd. Estimated production of Waurum is approximately 1,000 m³ for 2018. Chemical free property improvements especially in hydrophobicity, durability (both biological and weather resistance), dimensional stability, and hardness (www.waurum.com). • Thermo-mechanically modified timber with TMTMTM technology by KWS Timber Tech Ltd. (technology

provider). Production volume some hundreds of cubic metres per year, mainly for product and process testing

ThermoWood Association, founded in year 2000, has 16 member companies in eight countries. Production of ThermoWood has been increasing steadily for over 15 years. ThermoWood is a registered trademark owned by the International ThermoWood Association. The Finnish members of the International ThermoWood Association (Table 1) have eight production units with total production of 170,000 m³ of ThermoWood in 2017. Since there was a fire in the biggest ThermoWood production unit (Lunawood Soinlahti) in November 2017, resulting in a long production

break, the volume of ThermoWood produced is expected to grow only slightly in 2018.

new, and due to confidentiality issues the information is on rather general level:

**Other modification methods**

content/uploads/2017/09/kivipuu\_esite\_A4\_ENG\_v2.pdf)

with several different species (www.finestwood.fi).

**in Finland**

LUKE – Natural Resources Institute Finland, Yliopistokatu 6B, 80100 Joensuu, Finland

**Henrik HERÄJÄRVI**

<EMAIL_ADDRESS>
**Introduction**

ThermoWood Association.

subjective estimate of the author.

**Thermal modification**

## **Wood modification in Finland**

#### **Henrik HERÄJÄRVI**

LUKE – Natural Resources Institute Finland, Yliopistokatu 6B, 80100 Joensuu, Finland<EMAIL_ADDRESS>
## **Introduction**

54

Wine barrels, Iasi, Romania

Information in this report is based either on personal communications between the author and company representatives or websites of the companies. Prognosis regarding the ThermoWood® production in 2018 is a subjective estimate of the author.

## **Thermal modification**

The ThermoWood® process (www.thermowood.fi) was developed in Finland in the 1990s. Nowadays the International ThermoWood Association, founded in year 2000, has 16 member companies in eight countries. Production of ThermoWood has been increasing steadily for over 15 years. ThermoWood is a registered trademark owned by the International ThermoWood Association. The Finnish members of the International ThermoWood Association (Table 1) have eight production units with total production of 170,000 m³ of ThermoWood in 2017. Since there was a fire in the biggest ThermoWood production unit (Lunawood Soinlahti) in November 2017, resulting in a long production break, the volume of ThermoWood produced is expected to grow only slightly in 2018.

In addition to the registered ThermoWood producers, there is one company (www.rakennuspuu.fi/en) producing approximately 2,000 m³ thermally modified timber per year, but it does not belong to the International ThermoWood Association.

Thus, the total production of thermally modified wood in Finland was approximately 172,000 m³ in 2017.

## **Other modification methods**

The following points present other modified wood products commercialized in Finland. All products are rather new, and due to confidentiality issues the information is on rather general level:

Table 13 summarizes the production of modified wood products in Finland.

*Table 13: Wood modification technologies, producers, estimated production volumes (2017 or 2018), and production capacities in Finland in November 2018*

57

**Wood modification**

As a result of increasingly stringent constraints, biocidal restrictions and costly investments, the European regulations has imposed a reduced flexibility for wood preservative manufacturers. It is therefore necessary today to diversify the types of wood modification processes. The concept of modified wood in France has attracted considerable interest over the lasts years both with industry and academia, with activities in several modification

French activities in thermal modified timber (TMT) were studied since the 80s, and were mainly conducted in collaboration between universities and industries. Improvements of existing processes and material studies were focused in this research. The thermal modification is now well established in France with about 13 companies, working on various processes (retication®, WTT®, ThermoWood®, Thermostabilisation and Inductive heating), representing an annual production of heat modified woods around 35,000 m³/year. Actually, the studies are mainly focused on (i) the quality control of the produced thermal modified wood materials (Candelier *et al*. 2016)

Alongside thermal and chemical wood modification, there has been an interest in hydrophobation of wood. Academic and industrial companies from France, Switzerland and Austria just finished an EU WoodWisdom-Net project (BioCoPol – Enhancing wood durability and physical properties through innovative bio-based sustainable

Acylation of wood has been extensively studied using a wide range of chemicals, among them, acid anhydride, acyl chloride, ketene or even carboxylic acid. Even if no acetylated wood producer is present in France, the

Mixed acetic-fatty esters preservatives have been also recently developed by Lapeyre® industry and INP Toulouse. This method permits the grafting of acyl groups on wood leading to dimensionally stable treated wood bearing acetyl and fatty acid acyl chains, showing improved water repellence, which was recently unsuccessfully marketed

INRA, INPT and ENSIACET academic institutions worked on wood preservatives from ASMA (Anhydride succinite of methyl alkenoate), through a European project called SURFASAM. ASMA provides wood material with a Use-

In addition to the protection to fungal and insects degradations, manufacturers are now developing more flame retardant solutions. Piveteau Bois® company developed Igni-B, in collaboration with Arch Protection®, consisting in a resin impregnation, in addition to active substances, in order to definitively fix them in the wood following

Finally, WoodHa® company had obtained a durability certificate with the preservative system BIME®1, combining

and on (ii) the combination between thermal modification and biocide agents (Salman *et al*. 2017).

commercialization of Accoya® wood products in France has increased by 20% in 2017-2018.

Class 3, and this product is now the subject of requests from industrials (Final report SURFASAM).

**in France**

CIRAD – UPR BioWooEB, 343 98 Montpellier, and

BioWooEB, University of Montpellier, CIRAD, Montpellier, France

treatments), showing the potential of some of their formulations.

flame retardant and non-film forming saturator in aqueous phase.

by Lapeyre under the trade name of Wood Protect®.

the resin polymerization.

**Kévin CANDELIER**

<EMAIL_ADDRESS>
**Introduction**

methods, Table 14.

## **Wood modification in France**

#### **Kévin CANDELIER**

CIRAD – UPR BioWooEB, 343 98 Montpellier, and BioWooEB, University of Montpellier, CIRAD, Montpellier, France<EMAIL_ADDRESS>
## **Introduction**

56

Table 13 summarizes the production of modified wood products in Finland.

• Ekosampo Oy Ltd • HJT-Holz Oy Ltd • Oy Lunawood Ltd

*in November 2018*

Thermo-mechanical timber

TMTMTM technology

modification

Finestwood®

*Table 13: Wood modification technologies, producers, estimated production volumes (2017 or 2018), and production capacities in Finland*

**Technology / Brand Producer Production (2018) Annual Capacity** ThermoWood® Finnish members of the International 170,000 m3 170,000 + m3

International ThermoWood Association

• Stora Enso Wood Products Oy Ltd

Thermally modified wood Pieksämäen rakennuspuu Ltd. 2,000 m3 2,000 m3 Waurum® Paattimaakarit Ltd. 1,000 m3 10,000 m3 Kivipuu (Siligna®, Silica®) Aureskoski Ltd. / Lapuan Saha Ltd. 1,000 m3 20,000 m3

KWS Timber Tech Ltd. <500 m3 3,000 m3

• Suomen Lämpöpuu Oy Ltd

• Oy SWM-Wood Ltd

As a result of increasingly stringent constraints, biocidal restrictions and costly investments, the European regulations has imposed a reduced flexibility for wood preservative manufacturers. It is therefore necessary today to diversify the types of wood modification processes. The concept of modified wood in France has attracted considerable interest over the lasts years both with industry and academia, with activities in several modification methods, Table 14.

French activities in thermal modified timber (TMT) were studied since the 80s, and were mainly conducted in collaboration between universities and industries. Improvements of existing processes and material studies were focused in this research. The thermal modification is now well established in France with about 13 companies, working on various processes (retication®, WTT®, ThermoWood®, Thermostabilisation and Inductive heating), representing an annual production of heat modified woods around 35,000 m³/year. Actually, the studies are mainly focused on (i) the quality control of the produced thermal modified wood materials (Candelier *et al*. 2016) and on (ii) the combination between thermal modification and biocide agents (Salman *et al*. 2017).

Alongside thermal and chemical wood modification, there has been an interest in hydrophobation of wood. Academic and industrial companies from France, Switzerland and Austria just finished an EU WoodWisdom-Net project (BioCoPol – Enhancing wood durability and physical properties through innovative bio-based sustainable treatments), showing the potential of some of their formulations.

Acylation of wood has been extensively studied using a wide range of chemicals, among them, acid anhydride, acyl chloride, ketene or even carboxylic acid. Even if no acetylated wood producer is present in France, the commercialization of Accoya® wood products in France has increased by 20% in 2017-2018.

Mixed acetic-fatty esters preservatives have been also recently developed by Lapeyre® industry and INP Toulouse. This method permits the grafting of acyl groups on wood leading to dimensionally stable treated wood bearing acetyl and fatty acid acyl chains, showing improved water repellence, which was recently unsuccessfully marketed by Lapeyre under the trade name of Wood Protect®.

INRA, INPT and ENSIACET academic institutions worked on wood preservatives from ASMA (Anhydride succinite of methyl alkenoate), through a European project called SURFASAM. ASMA provides wood material with a Use-Class 3, and this product is now the subject of requests from industrials (Final report SURFASAM).

In addition to the protection to fungal and insects degradations, manufacturers are now developing more flame retardant solutions. Piveteau Bois® company developed Igni-B, in collaboration with Arch Protection®, consisting in a resin impregnation, in addition to active substances, in order to definitively fix them in the wood following the resin polymerization.

Finally, WoodHa® company had obtained a durability certificate with the preservative system BIME®1, combining flame retardant and non-film forming saturator in aqueous phase.

59

**Modification technologies and production volumes**

Timber from different commercialised modification processes are mainly harvested in French and closed European forests, but they are also imported directly into France for use. The main wood species transformed by

this different processes are mainly: pine, Douglas fir, beech, ash, poplar, etc. (Gérardin 2016).

Figure 23 show some examples of the uses of modified wood in France.

wood- a review. *Annals of Forest Science* 73(3), 559-570.

europa.eu/publication/rcn/11020\_en.html

demand for modified wood.

*in an autoclave (right).*

**References**

**Practical examples**

There are a range of evolving modification processes being commercialized within France, and due to the relative newness to the market are still in the expansion phase. Table 13 gives a brief overview of these modification methods. In addition, France has a high demand for quality products, meaning that there is a strong import

*Figure 23: The use of modified wood in France: siding of thermally modified poplar wood by Bois Durable de Bourgogne® company (left), thermal-modification kiln, Jartek®, 20 m³, Bois Durable de Bourgogne® (middle), and WoodenHa® process, fire-retardant impregnation*

Gérardin P (2016). New alternatives for wood preservation based on thermal and chemical modification of

Candelier K, Thévenon MF, Pétrissans A, Dumarçay S, Gérardin P, Pétrissans M (2016). Control of wood thermal

Final Report - SURFASAM (Innovative "green wood treatment" to achieve Risk Class4 protection) https://cordis.

Salman S, Thévenon MF, Pétrissans A, Dumarçay S, Candelier K, Gérardin P (2017). Improvement of the durability

treatment and its effects on decay resistance: a review. *Annals of Forest* 73(3), 571-583.

of heat-treated wood against termites. *Maderas: Ciencia y Tecnología* 19(3), 317-328.

## **Modification technologies and production volumes**

There are a range of evolving modification processes being commercialized within France, and due to the relative newness to the market are still in the expansion phase. Table 13 gives a brief overview of these modification methods. In addition, France has a high demand for quality products, meaning that there is a strong import demand for modified wood.

Timber from different commercialised modification processes are mainly harvested in French and closed European forests, but they are also imported directly into France for use. The main wood species transformed by this different processes are mainly: pine, Douglas fir, beech, ash, poplar, etc. (Gérardin 2016).

### **Practical examples**

Figure 23 show some examples of the uses of modified wood in France.

*Figure 23: The use of modified wood in France: siding of thermally modified poplar wood by Bois Durable de Bourgogne® company (left), thermal-modification kiln, Jartek®, 20 m³, Bois Durable de Bourgogne® (middle), and WoodenHa® process, fire-retardant impregnation in an autoclave (right).*

## **References**

58

*Table 14: Wood modification technologies, producers, companies and production volumes in France*

Part of the ThermoWood® Association., Jartek®

Thermal modification ECOLWOOD - ThermoVacuum process, Maspell® 1,500 m³/year mainly used for

**Annual volumes n.a. = not available**

cladding and decking

furnitures

n.a.

8,000 m³/year

exterior furniure.

exterior furniture.

decking

mainly hardwood timber

3,000 m³/year, mainly used for siding, cladding, decking, joinery and

1,500 m³/year, mainly used for siding, decking, parquet, garden furniture, pool surrounds and exterior joinery.

8,000 m³/year, mainly used for Cladding, flooring and plywood

n.a., A JARTEK thermally modification,

n.a., mainly used for siding, decking,

8,000 m³ mainly used for cladding and

n.a., mainly used for siding, decking, parquet, exterior furniture.

n.a., mainly used for siding, decking,

n.a., used for coopers in wine industry

4,000 m³/year, mainly used for siding,

n.a., mainly used for exterior joinery in

n.a., mainly used for siding and wood

n.a., mainly used for siding and wood

decking, exterior furniture.

pine wood

building material.

building material.

**Producer, process short description**

www.boisdurablesdebourgogne.fr

Thermal modification HIGH TECH WOODS n.a.

**and website**

Thermal modification BOIS DURABLE DE BOURGOGNE® -.

WTT process THERMO COLOR BOIS, WTT Process

www.thermo-color-bois.fr

www.dumoulin-bois.fr

http://www.sivalbp.fr/

https://en.ducerf.com/

Thermostabilisation SYLVABP, Baschild® process, Commercialization under

www.sefwood.com

Ecothermo® trend www.sivalbp.com

www.bois-thermo.com/

Thermal modification LIGNIVALYS, Stillwood® process perfomed with a Maspell®

Retification RETIWOOD, N.C n.a.

Developped in coopération with INP Toulouse

LAPEYRE – Woodprotect®, Vacuum/pressure impregnation

Thermal modification BMT PRODUCTION, BESSON® process

vacuum oven www.lignivalys.fr

www.laglasse.net/

www.kit-foret.fr

+ heating 140°C-2H

Fire retardant PIVETEAU BOIS / ARCH PROTECTION, Igni-B Resin impregnation

Patent WO 03 084 723 [58]

http://www.piveteaubois.com

Fire retardant WOODHA®, BIME®1, flame retardant and non-film forming saturator in aqueous phase http://www.woodenha.com

Retification SEFWOOD, Bois rétifié® process

Thermal modification BOIS DURABLE CENTRE FRANCE, ThermoVuelto® process www.parquet-chene-massif.com

Thermal modification DUMOULIN, BESSON® process, Commercializatiuon under Lunawood® trend (www.lunawood.fi)

**Wood modification technology**

ThermoWood Silvalbp

Inductive heating Laglasse

Anhydrides mixtes traetement

Thermal modification KIT FORET, N.C

ThermoWood DUCERF Group

61

4,000-6,000 m³

1,500-2,000 m³

1,500-2,000 m³

n.a.

n.a.

n.a.

**Wood modification**

University of Göttingen, Wood Biology and Wood Products, Faculty of Forest Sciences, Buesgenweg 4, 37077 Göttingen,

Within the past decades, wood modification technologies were developed in different European countries, with focus on countries of the northern hemisphere (e.g. Austria, Finland, Germany, Norway, The Netherlands). Motivated to create alternatives to new, innovative building materials, preservative treated wood as well as endangered tropical timber, intensive fundamental research made possibly the commercialization of some of these technologies. In Germany, production plants for thermally modified timber and various chemical modifications commenced operation towards the end of 20th century. Initially focused on solid wood,

predominantly chemical wood modification was over time successfully applied with wood-based composites.

**Modification technologies and production volumes**

Tables 15 and 16 illustrate wood modification technologies, for which production plants do exist in Germany. The production volumes are premised either on estimates by the Institute of Wood Technology Dresden (IHD) in case of thermally modified timber (Scheiding 2018) or taken from manufacturer´s websites. Production volumes may

*Table 15: Wood modification technologies, producers and production volumes – thermally modified wood. n.a. = not available; \* currently*

**technology Producer, process short description and website Annual volumes produced**

In comparison with thermal modification plants, a similar amount of companies operates chemical modification mainly with phenolic resins or treatment with hot-melting waxes (Table 16). Contrary to heat treatment applied

BES Bad Essener Sägewerk GmbH & Co. KG; open process;

Timura Holzmanufaktur GmbH; closed vacuum process;

Holzindustrie Templin GmbH; open process (presumed);

Holzbodenwerk Krottenthaler GmbH & Co. KG; closed pressure

**in Germany**

<EMAIL_ADDRESS><EMAIL_ADDRESS>
differ to the precise and actual production of the respective company.

*insolvent; production continues; \*\* production plant shall be sold; production stopped.*

www.timura.de

www.jep-parkett.de

www.hitemplin.de

www.firstwood.de\*\*

http://www.bad-essener-saegewerk.de\*

JEP Hardwood Flooring GmbH; open process;

Firstwood (Golden Mile GmbH); open process;

process; www.holzbodenwerk.de

**Holger MILITZ, Lukas EMMERICH**

**Introduction**

**Wood modification**

Thermal modification

at approx. 180-220°C

Germany

## **Wood modification in Germany**

#### **Holger MILITZ, Lukas EMMERICH**

University of Göttingen, Wood Biology and Wood Products, Faculty of Forest Sciences, Buesgenweg 4, 37077 Göttingen, Germany

<EMAIL_ADDRESS><EMAIL_ADDRESS>
### **Introduction**

60

Within the past decades, wood modification technologies were developed in different European countries, with focus on countries of the northern hemisphere (e.g. Austria, Finland, Germany, Norway, The Netherlands). Motivated to create alternatives to new, innovative building materials, preservative treated wood as well as endangered tropical timber, intensive fundamental research made possibly the commercialization of some of these technologies. In Germany, production plants for thermally modified timber and various chemical modifications commenced operation towards the end of 20th century. Initially focused on solid wood, predominantly chemical wood modification was over time successfully applied with wood-based composites.

### **Modification technologies and production volumes**

Tables 15 and 16 illustrate wood modification technologies, for which production plants do exist in Germany. The production volumes are premised either on estimates by the Institute of Wood Technology Dresden (IHD) in case of thermally modified timber (Scheiding 2018) or taken from manufacturer´s websites. Production volumes may differ to the precise and actual production of the respective company.

*Table 15: Wood modification technologies, producers and production volumes – thermally modified wood. n.a. = not available; \* currently insolvent; production continues; \*\* production plant shall be sold; production stopped.*

In comparison with thermal modification plants, a similar amount of companies operates chemical modification mainly with phenolic resins or treatment with hot-melting waxes (Table 16). Contrary to heat treatment applied

to solid wood, phenolic resins are used to merge and finish veneers to plywood, laminated veneer lumber or synthetic resin densified wood. Such wood-based composites enable to meet a range of specific customer needs. Supplemented by specific additives (e.g. flame retardants), very individual customer requirements (mechanical strength, insulating properties, noise absorption, corrosion resistance, flame protection etc.) can be met with such technologies. Thus, since respective products are usually made to customized demands and some production plants are still in the start-up phase (e.g. BauBuche®), precise annual volumes produced are not available or disclosed (Table 16). Besides existing production plants using reactive modifying resins, a production plant for acetylated wood (Accoya®) is planned near Freiburg (Germany). However, the actual implementation was postponed up till now (EUWID 2015).

*Table 16: Wood modification technologies, producers, companies and products – Chemical and wax treatment*

### **Practical examples**

Figure 24 illustrates products made out of modified wood for practical application. Besides several applications outdoors (decking (a), facades, garden furniture), thermally modified wood is used and favoured for interior flooring and furniture due to its changed optical appearance. Innovative laminated materials as mentioned in Table 15, enable the use for wooden constructions (BauBuche® (b)), interior floors and walls inside transport vehicles (e.g. Delignit®) and many other customized solutions (c).

63

**Future perspectives and processes ready to**

Since the early 2000s, intensive research activities on chemical wood modification technologies were conducted by the University of Göttingen, closely linked to the wood-working industry. Focus was on wood modification with DMDHEU (formerly: Belmadur®) and a 'combi-treatment' of thermal treatment followed by an impregnation with melamine resins, in order to replace teak wood in the boat building industry. For both technologies, processes were developed up to pilot scale and ready to industrialize. Currently, several activities ongoing between the University of Göttingen, chemicals producer and wood-working industry show promising prospects for both modification technologies, pushed by an increasing demand for environmentally benign technologies to establish

EUWID – Holz und Holzwerkstoffe (2015). Solvay stellt Bau von Accoya-Werk vorerst zurück. Published online: 26 Nov 2015, URL: https://www.euwid-holz.de/news/holzprodukte/einzelansicht/Artikel/solvay-stellt-bau-von-

**industrialize**

innovative bio-based materials.

accoya-werk-vorerst-zurueck.html Scheiding W (2018). Personal communication.

**References**

*Figure 24: Densified resin-impregnated and laminated beech veneer from Deutsche Holzveredelung Schmeing GmbH & Co. KG (left), and Baubuche from Pollmeier Massivholz GmbH & Co. KG in a fram construction under construction at Neue Holzbau AG Lungern (right)*

#### **Future perspectives and processes ready to industrialize**

Since the early 2000s, intensive research activities on chemical wood modification technologies were conducted by the University of Göttingen, closely linked to the wood-working industry. Focus was on wood modification with DMDHEU (formerly: Belmadur®) and a 'combi-treatment' of thermal treatment followed by an impregnation with melamine resins, in order to replace teak wood in the boat building industry. For both technologies, processes were developed up to pilot scale and ready to industrialize. Currently, several activities ongoing between the University of Göttingen, chemicals producer and wood-working industry show promising prospects for both modification technologies, pushed by an increasing demand for environmentally benign technologies to establish innovative bio-based materials.

### **References**

62

to solid wood, phenolic resins are used to merge and finish veneers to plywood, laminated veneer lumber or synthetic resin densified wood. Such wood-based composites enable to meet a range of specific customer needs. Supplemented by specific additives (e.g. flame retardants), very individual customer requirements (mechanical strength, insulating properties, noise absorption, corrosion resistance, flame protection etc.) can be met with such technologies. Thus, since respective products are usually made to customized demands and some production plants are still in the start-up phase (e.g. BauBuche®), precise annual volumes produced are not available or disclosed (Table 16). Besides existing production plants using reactive modifying resins, a production plant for acetylated wood (Accoya®) is planned near Freiburg (Germany). However, the actual implementation was

*Table 16: Wood modification technologies, producers, companies and products – Chemical and wax treatment*

synthetic resin densified wood; additional refining steps;

Röchling SE & Co. KG; synthetic resin densified wood;

http://www.dehonit.de/page/en/homepage.php

under temperature supply; http://www.dauerholz.de/

Wax treatment Dauerholz AG; impregnation of solid wood with a hot-melting wax

**technology Producer, process short description and website Products (brand names)**

Delignit®, Delignit®, Feinholz®, carbonwood®, obo-Festholz®, Panzerholz®, VANyCARE®

BauBuche®

Lignostone®

Dehonit®

Dauerholz®

Delignit AG/ Blomberger Holzindustrie GmbH; wood-based panels;

Pollmeier Massivholz GmbH & Co. KG; laminated veneer lumber: parallel oriented veneers; https://www.pollmeier.com/en/

Deutsche Holzveredelung Schmeing GmbH & Co. KG; synthetic

Figure 24 illustrates products made out of modified wood for practical application. Besides several applications outdoors (decking (a), facades, garden furniture), thermally modified wood is used and favoured for interior flooring and furniture due to its changed optical appearance. Innovative laminated materials as mentioned in Table 15, enable the use for wooden constructions (BauBuche® (b)), interior floors and walls inside transport

*Figure 24: Densified resin-impregnated and laminated beech veneer from Deutsche Holzveredelung Schmeing GmbH & Co. KG (left), and Baubuche from Pollmeier Massivholz GmbH & Co. KG in a fram construction under construction at Neue Holzbau AG Lungern (right)*

postponed up till now (EUWID 2015).

**Practical examples**

www.delignit.de

https://www.roechling.com/de/

resin densified wood;

vehicles (e.g. Delignit®) and many other customized solutions (c).

**Wood modification**

Chemical modification with phenolic resins

> EUWID – Holz und Holzwerkstoffe (2015). Solvay stellt Bau von Accoya-Werk vorerst zurück. Published online: 26 Nov 2015, URL: https://www.euwid-holz.de/news/holzprodukte/einzelansicht/Artikel/solvay-stellt-bau-vonaccoya-werk-vorerst-zurueck.html

Scheiding W (2018). Personal communication.

64

65

**Wood modification**

**Research and industrialization of wood modification**

Industrial applications of wood modification processes such as thermal modification, acetylation and

Research in the field of wood modification exist at two institutes: Forest Research Institute "Demeter" and

In the field of wood modification, the Laboratory of Wood Anatomy and Technology of FRI is equipped with a custom made 1L stainless steel reactor capable of carrying out impregnations (capacity for vacuum = -0.8bar (gauge), capacity for pressure = 12bar), hydrothermal (steam), thermo-hydro-mechanical treatment at temperatures up to 230°C. The process is almost fully automated using labview software and has a large degree of adaptability to special needs. There is also a precision mini-heated press with plate dimensions of 100x100mm with precision controlled temperature that can be mounted onto universal testing machines for accurate pressure/

In cooperation with the FRI Athens, WST lab at TEI of Thessaly carries out two separate research projects:

a) the resistance of European beech (*Fagus sylvatica* L.) wood impregnated at high pressure with two nanodispersions of zinc oxide (nano-ZnO) and zinc borate (nano-ZnB) is presently examined against several

properties, following a steel vessel treatment using the empty cell process (Lowry method). The effect of

In another technical project, the weathering and biological resistance of industrially produced furfurylated wood, of three wood species, exposed outdoors, has been examined under the climatic conditions of central Greece.

b) beech and black pine wood is examined for oil-retention, adsorption, swelling and tensile strength

furfurylation in Greece are very rare and to date have no industrial implementation.

thickness control. Data acquisition is carried out with Labview virtual instruments.

• Enhancement of wood properties by impregnation with nano-metal dispersions

The current research activity related to wood modification is mainly focused on

University of Thessaly, Department of Forestry, Wood Sciences and Design

**in Greece**

Lab of Wood Science and Technology, Karditsa, Greece

University of Thessaly (TEI of Thessaly) / WFDT Dept.

• thermo-hydro-mechanical treatment of wood • Densified/melamine formaldehyde modified wood.

• Hydrothermal modification of wood

**TEI of Theessaly**

termite species; and,

surface treatment with turpentine is investigated.

**George I. MANTANIS**

<EMAIL_ADDRESS>
**in Greece**

**Demeter**

## **Wood modification in Greece**

#### **George I. MANTANIS**

University of Thessaly, Department of Forestry, Wood Sciences and Design Lab of Wood Science and Technology, Karditsa, Greece<EMAIL_ADDRESS>
#### **Research and industrialization of wood modification in Greece**

Industrial applications of wood modification processes such as thermal modification, acetylation and furfurylation in Greece are very rare and to date have no industrial implementation.

Research in the field of wood modification exist at two institutes: Forest Research Institute "Demeter" and University of Thessaly (TEI of Thessaly) / WFDT Dept.

### **Demeter**

In the field of wood modification, the Laboratory of Wood Anatomy and Technology of FRI is equipped with a custom made 1L stainless steel reactor capable of carrying out impregnations (capacity for vacuum = -0.8bar (gauge), capacity for pressure = 12bar), hydrothermal (steam), thermo-hydro-mechanical treatment at temperatures up to 230°C. The process is almost fully automated using labview software and has a large degree of adaptability to special needs. There is also a precision mini-heated press with plate dimensions of 100x100mm with precision controlled temperature that can be mounted onto universal testing machines for accurate pressure/ thickness control. Data acquisition is carried out with Labview virtual instruments.

The current research activity related to wood modification is mainly focused on

#### **TEI of Theessaly**

64

Thermally modified wood, Hudiksvall, Sweden

In cooperation with the FRI Athens, WST lab at TEI of Thessaly carries out two separate research projects:

In another technical project, the weathering and biological resistance of industrially produced furfurylated wood, of three wood species, exposed outdoors, has been examined under the climatic conditions of central Greece.

67

**Annual volumes produced and companies involved in the process**

50 m³ (Production capacity)

~20 m³ (2016)

**Wood modification**

University of Sopron, Faculty of Engineering, Wood Sciences and Applied Arts, Bajcsy-Zsilinszky u. 4, Sopron, Hungary

Wood modification technologies date back several decades at the University of Sopron. Among the first investigations were high pressure and temperature steaming, and ammonia treatment of black locust. The demand for modified wood material has increased Europe-wide, due to the commercialisation of different wood modification processes during the last few decades. Wood modification accounts for much of the research objectives in our institute. Wood modification processes indicate continuously new challenges. During the last years, special attention has been given to heat treatment processes in vegetable oils and paraffin, acetylation and some impregnation processes. As in the last years, nanotechnology came to the front, with investigations into the application possibility of nano-scale materials in wood industry. Unfortunately, the wide-spread research activity in the field of wood modification is not coupled with active industrial applications in Hungary. However, there

**Modification technologies and production volumes**

Compression parallel to the grain, to improve the bendability of wood (accordionisation), Table 17. The purpose of the longitudinal compression of wood is to make it more bendable. Several factors influence the outcome of compression (wood species and quality, moisture content, temperature, compression rate, etc.). Most hardwood species with initial moisture content above 20% can be compressed. The wood is normally softened by steaming, and during the process, kept at temperatures above 80°C. While compressed in fibre direction it needs to be restricted within the compression chamber to prevent the wood from suckling. Frictional forces need to be minimized so that the transformation is performed at even rate. The middle lamellae, mostly consisting of lignin and hemicelluloses, are softened by thermo-hydro modification, allowing of the wood fibres with high cellulose content to slip during compression, and the longitudinal cell walls crinkle. Consequently, the elasticity of the

wood decreases, thus it will be much easier to bend, even when dry and at room temperature.

*Table 17: Wood modification technologies, producers, companies and production volumes*

Compwood Products Kft.

**and website**

**Producer, process short description**

Thermo-Hygro-Mechanical treatment. www.compwood-products.com

**in Hungary**

**Miklós BAK, Róbert NÉMETH, Mátyás BÁDER**

<EMAIL_ADDRESS><EMAIL_ADDRESS>
were some trials with thermal modification technologies.

<EMAIL_ADDRESS>
**Introduction**

**Wood modification technology**

Compressed wood parallel to the grain (accordionisation)

## **Wood modification in Hungary**

#### **Miklós BAK, Róbert NÉMETH, Mátyás BÁDER**

University of Sopron, Faculty of Engineering, Wood Sciences and Applied Arts, Bajcsy-Zsilinszky u. 4, Sopron, Hungary<EMAIL_ADDRESS><EMAIL_ADDRESS><EMAIL_ADDRESS>
## **Introduction**

66

Shou Sugi Ban or Yakisugi (charred) wood, Higashiyama district, Kyoto, Japan

Wood modification technologies date back several decades at the University of Sopron. Among the first investigations were high pressure and temperature steaming, and ammonia treatment of black locust. The demand for modified wood material has increased Europe-wide, due to the commercialisation of different wood modification processes during the last few decades. Wood modification accounts for much of the research objectives in our institute. Wood modification processes indicate continuously new challenges. During the last years, special attention has been given to heat treatment processes in vegetable oils and paraffin, acetylation and some impregnation processes. As in the last years, nanotechnology came to the front, with investigations into the application possibility of nano-scale materials in wood industry. Unfortunately, the wide-spread research activity in the field of wood modification is not coupled with active industrial applications in Hungary. However, there were some trials with thermal modification technologies.

## **Modification technologies and production volumes**

Compression parallel to the grain, to improve the bendability of wood (accordionisation), Table 17. The purpose of the longitudinal compression of wood is to make it more bendable. Several factors influence the outcome of compression (wood species and quality, moisture content, temperature, compression rate, etc.). Most hardwood species with initial moisture content above 20% can be compressed. The wood is normally softened by steaming, and during the process, kept at temperatures above 80°C. While compressed in fibre direction it needs to be restricted within the compression chamber to prevent the wood from suckling. Frictional forces need to be minimized so that the transformation is performed at even rate. The middle lamellae, mostly consisting of lignin and hemicelluloses, are softened by thermo-hydro modification, allowing of the wood fibres with high cellulose content to slip during compression, and the longitudinal cell walls crinkle. Consequently, the elasticity of the wood decreases, thus it will be much easier to bend, even when dry and at room temperature.

*Table 17: Wood modification technologies, producers, companies and production volumes*

## **Practical examples**

There is a wide range of utilization fields for the wood material produced by the Compwood technology. One of the most interesting utilization is the production of wooden springs. With the use of these springs, it is possible to produce upholstered furniture based only on biomaterials. Another common field of utilization is the production of bent furniture and parts. Special applications are design elements (Figure 25) in interior design, or music instruments, sport instruments, ship building, toys, medical aid equipment, etc.

69

**Wood modification**

DJ Timber Consultancy Ltd., 15 Heol Pen Y Coed, Cimla, Neath, SA11 3SP, UK<EMAIL_ADDRESS>
Whilst there are no research groups directly active in areas of wood modification in Ireland, there is considerable interest from architects, specifiers and home-owners to use commercially available modified wood. Much of the issues surrounding the development of wood modification in Europe has been the timber resources available, which have been predominantly Sitka spruce. Indeed in 1998, a technical review of the potential of wood

modification in Ireland (Birkinshaw 1998) assessed the scientific and economic viability of commercialisation in

*"Timber utilisation patterns in Ireland differ from those in other European countries, but many of the same environmental and economic pressures apply. Before getting involved in modification, Irish mills and joinery manufacturers will require detailed cost information. Costs are going to be considerable, as the nature of the processes, involving corrosion-resistant pressure vessels, ovens and chemical handling, recovery and storage facilities, indicates a large investment compared with a CCA plant. It is therefore important to realise that acety1ated timber is not simply a new method of preservation which will compete with use of CCA or borates, but is a way of upgrading the material to allow it to be used for higher value*

*A significant cost benefit may arise through savings in waste wood disposal. European and national regulations are making handling, and in particular, disposal, of CCA treated materials problematic and potentially expensive. Acetylated wood can be dealt with and disposed of without any special precautions, and no environmental hazards are presented.*

*The investment required is within the capability of the large wood composite companies, but would be more of a challenge for the smaller units involved in solid wood processing. Economies of scale make it very difficult to envisage more than a very small number of modification plants in Ireland, but decisions about how these will be owned and operated rest with*

With the development of greater commercialisation across Europe, supplies of modified materials have become more commonplace and are commonly stocked by timber suppliers across the country. However, the interest in acetylation explored by Birkinshaw (1998) led to ongoing activities by Medite, a large-scale MDF manufacturer in Ireland, which has led to the launch of Tricoya®, with joint investment in a new acetylation plant in Hull, UK,

As indicated above, the availability of modified wood via timber merchants has allowed the marketing of

production by these merchants, activities of some may lead to future commercial activities.

thermally modified, acetylated, furfurylated and silicon treated wood. Whilst there has been no confirmed direct

As an example, Correll Timber advertise supplies of Accoya and ThermoWood, as well as a modified hardwood sold under the brand name THERMA wood cladding, where it advertises a moisture content reduced down to 16% compared to the untreated 27%, Figure 26. Another company, Erin Trading, have exclusive sales rights for

**A summary of wood modification activities**

**in Ireland**

Ireland, within which it was stated:

**Dennis JONES**

*applications.*

Figure 15.

*the industry and State bodies."*

Thermory in both the UK and Ireland.

*Figure 25: Examples of modified wood in the form of bent components*

## **Wood modification in Ireland**

#### **Dennis JONES**

68

**Practical examples**

There is a wide range of utilization fields for the wood material produced by the Compwood technology. One of the most interesting utilization is the production of wooden springs. With the use of these springs, it is possible to produce upholstered furniture based only on biomaterials. Another common field of utilization is the production of bent furniture and parts. Special applications are design elements (Figure 25) in interior design, or music

instruments, sport instruments, ship building, toys, medical aid equipment, etc.

*Figure 25: Examples of modified wood in the form of bent components*

DJ Timber Consultancy Ltd., 15 Heol Pen Y Coed, Cimla, Neath, SA11 3SP, UK<EMAIL_ADDRESS>
### **A summary of wood modification activities**

Whilst there are no research groups directly active in areas of wood modification in Ireland, there is considerable interest from architects, specifiers and home-owners to use commercially available modified wood. Much of the issues surrounding the development of wood modification in Europe has been the timber resources available, which have been predominantly Sitka spruce. Indeed in 1998, a technical review of the potential of wood modification in Ireland (Birkinshaw 1998) assessed the scientific and economic viability of commercialisation in Ireland, within which it was stated:

*"Timber utilisation patterns in Ireland differ from those in other European countries, but many of the same environmental and economic pressures apply. Before getting involved in modification, Irish mills and joinery manufacturers will require detailed cost information. Costs are going to be considerable, as the nature of the processes, involving corrosion-resistant pressure vessels, ovens and chemical handling, recovery and storage facilities, indicates a large investment compared with a CCA plant. It is therefore important to realise that acety1ated timber is not simply a new method of preservation which will compete with use of CCA or borates, but is a way of upgrading the material to allow it to be used for higher value applications.*

*A significant cost benefit may arise through savings in waste wood disposal. European and national regulations are making handling, and in particular, disposal, of CCA treated materials problematic and potentially expensive. Acetylated wood can be dealt with and disposed of without any special precautions, and no environmental hazards are presented.*

*The investment required is within the capability of the large wood composite companies, but would be more of a challenge for the smaller units involved in solid wood processing. Economies of scale make it very difficult to envisage more than a very small number of modification plants in Ireland, but decisions about how these will be owned and operated rest with the industry and State bodies."*

With the development of greater commercialisation across Europe, supplies of modified materials have become more commonplace and are commonly stocked by timber suppliers across the country. However, the interest in acetylation explored by Birkinshaw (1998) led to ongoing activities by Medite, a large-scale MDF manufacturer in Ireland, which has led to the launch of Tricoya®, with joint investment in a new acetylation plant in Hull, UK, Figure 15.

As indicated above, the availability of modified wood via timber merchants has allowed the marketing of thermally modified, acetylated, furfurylated and silicon treated wood. Whilst there has been no confirmed direct production by these merchants, activities of some may lead to future commercial activities.

As an example, Correll Timber advertise supplies of Accoya and ThermoWood, as well as a modified hardwood sold under the brand name THERMA wood cladding, where it advertises a moisture content reduced down to 16% compared to the untreated 27%, Figure 26. Another company, Erin Trading, have exclusive sales rights for Thermory in both the UK and Ireland.

*Figure 26: Example of Accoya board (left), and ThermoWood cladding on St Andrews College, Dublin (right)*

#### **References**

Birkinshaw C (1998). Chemically modified wood - a review with consideration of the opportunities for application to Irish timber. *Irish Timber* 55(2), 21-34.

71

**Wood modification**

**Giacomo GOLI¹, Luigi TODARO², Ottaviano ALLEGRETTI³, Manuela ROMAGNOLI⁴**

With the development of thermal modification technologies in northern countries, Italy has also developed its own processes and technologies starting since 2000. In the country the industries active in the wood drying process, starting from their technologies, have developed different treatment processes. As regards the physical modification of wood intended as densification processes, the sector has been active in Italy for over 50 years. Products and plants for the chemical modification of wood are also very rare apart impregnation with salts with different purposes such as durability or fire-retardant. Mild processes, such as treatment with water, at

**Modification technologies and production volumes**

Thermally modified timber is at present produced in Italy for different purposes such as durability in external applications, aesthetics in internal applications. Practical uses are furniture, boat flooring, cladding, decking, and fences. Ranprex is used in different contexts where a stable, light and resilient material is needed. Some examples

*Figure 27: Certified window in thermally modified beech (left), [b] decking in thermally modified ash (middle), furniture in thermally*

As shown in Table 18, in the field of thermal modification technologies plants, four industries are actually active in

¹GESAAF – University of Florence, Via San Bonaventura 13, 50145 Firenze, Italy<EMAIL_ADDRESS>2SAFE – University of Basilicata, V.le Ateneo Lucano 10, 85100 Potenza, Italy<EMAIL_ADDRESS>
³CNR-IVALSA, via Biasi, 75, 38010, San Michele all'Adige (TN), Italy<EMAIL_ADDRESS>⁴DIBAF – University of Tuscia, S. Camillo de Lellis snc, 01100 Viterbo, Italy<EMAIL_ADDRESS>
temperature below 100°C in alkaline medium and vaporization, are often used in Italy.

**in Italy**

**Introduction**

are shown in Figures 27 and 28.

*modified ash (left)*

Italy.

## **Wood modification in Italy**

#### **Giacomo GOLI¹, Luigi TODARO², Ottaviano ALLEGRETTI³, Manuela ROMAGNOLI⁴**

¹GESAAF – University of Florence, Via San Bonaventura 13, 50145 Firenze, Italy<EMAIL_ADDRESS>2SAFE – University of Basilicata, V.le Ateneo Lucano 10, 85100 Potenza, Italy<EMAIL_ADDRESS>³CNR-IVALSA, via Biasi, 75, 38010, San Michele all'Adige (TN), Italy<EMAIL_ADDRESS>⁴DIBAF – University of Tuscia, S. Camillo de Lellis snc, 01100 Viterbo, Italy<EMAIL_ADDRESS>
## **Introduction**

70

**References**

to Irish timber. *Irish Timber* 55(2), 21-34.

*Figure 26: Example of Accoya board (left), and ThermoWood cladding on St Andrews College, Dublin (right)*

Birkinshaw C (1998). Chemically modified wood - a review with consideration of the opportunities for application

With the development of thermal modification technologies in northern countries, Italy has also developed its own processes and technologies starting since 2000. In the country the industries active in the wood drying process, starting from their technologies, have developed different treatment processes. As regards the physical modification of wood intended as densification processes, the sector has been active in Italy for over 50 years. Products and plants for the chemical modification of wood are also very rare apart impregnation with salts with different purposes such as durability or fire-retardant. Mild processes, such as treatment with water, at temperature below 100°C in alkaline medium and vaporization, are often used in Italy.

## **Modification technologies and production volumes**

As shown in Table 18, in the field of thermal modification technologies plants, four industries are actually active in Italy.

Thermally modified timber is at present produced in Italy for different purposes such as durability in external applications, aesthetics in internal applications. Practical uses are furniture, boat flooring, cladding, decking, and fences. Ranprex is used in different contexts where a stable, light and resilient material is needed. Some examples are shown in Figures 27 and 28.

*Figure 27: Certified window in thermally modified beech (left), [b] decking in thermally modified ash (middle), furniture in thermally modified ash (left)*

**Figure 28:** *Decking in thermally modified ash (left), cladding in thermally modified ash (middle), gears made of Ranprex (right)*

*Table 18: Wood modification technologies, producers, companies and production volumes*

73

10,000 m³

**Wood modification**

Latvia is the fourth country in Europe (after the Finland, Sweden and Slovenia) in terms of largest proportion of land area covered by forests and other wooded lands (FAO). Forests and overgrown agricultural lands occupy 3.22 million ha or 50% of the country's territory (Latvian National Forest Inventory). The forests of Latvia are dominated by three tree species – Scots pine, Norway spruce and birch species (silver and downy birch); together they constitute 73.8% of the total forest area (according to NFI data). The proportion of pine stands is 28.9%, but the proportion of spruce and birch stands – 17.0% and 27.9%. The remaining forest areas are occupied by stands of black alder (5.1%), grey alder (9.8%), aspen (7.7%), ash and oak (1.5 %), and other tree species (2%). The coniferous

Thermally modified timber (TMT) is the only modified wood products that is commercialized in Latvia, and SOTRA ENSO is dominating the production with an annual volume of 10,000 m³ TMT in Stora Enso's treatment facility in Launkalne, Latvia. Launkalne sawmill is located in the parish of Krogzemji, Valkas district in close proximity to main roads and also the forestry region of Latvia. The sawmill produces sawn spruce and pine with new machinery

There is additionally 3-5 small companies producing TMT in Latvia, with a total annual production of about 2,000 m³,

**technology Producer, process short description and website Annual volumes produced**

AS Stora Enso Latvija, Thermal modified timber for constructive use and flooring. Thermo-S and Thermo D products; KOMO

Thermal modification 3-5 small companys producing thermally modified timber 2,000 m³ (all together)

and a new saw line. During its two years of operation, the sawing capacity has grown to 215,000 m³.

stands in general occupy 46% of the total forest area, but stands of deciduous trees – 54%.

**Wood modification in Latvia**

*Table 19: Wood modification technologies, producers, companies and production volumes*

certificated for thermally modified timber

**in Latvia**

Latvian Stare institute of Wood Chemistr 27 Dzerbenes St., 1006 Riga, Latvia

**Bruno ANDERSONS**

<EMAIL_ADDRESS>
Table 19.

**Wood modification**

Thermal modification (ThermoWood)

**Introduction**

## **Wood modification in Latvia**

#### **Bruno ANDERSONS**

Latvian Stare institute of Wood Chemistr 27 Dzerbenes St., 1006 Riga, Latvia<EMAIL_ADDRESS>
### **Introduction**

72

**Figure 28:** *Decking in thermally modified ash (left), cladding in thermally modified ash (middle), gears made of Ranprex (right)*

**Annual volumes produced and companies**