CEN/TS 15679:2007

SLOVENSKI STANDARD
01-april-2008
Toplotno obdelan les - Definicije in lastnosti
Thermal Modified Timber - Definitions and characteristics
Thermisch modifiziertes Holz - Definitionen und Eigenschaften
Bois modifié thermiquement - Définitions et caractéristiques
Ta slovenski standard je istoveten z: CEN/TS 15679:2007
ICS:
01.040.79
79.040
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL SPECIFICATION
CEN/TS 15679
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
November 2007
ICS 01.040.79; 79.040
English Version
Thermal Modified Timber - Definitions and characteristics
Bois Modifié Thermiquement - Définitions et Thermisch modifiziertes Holz - Definitionen und
caractéristiques Eigenschaften
This Technical Specification (CEN/TS) was approved by CEN on 15 November 2007 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15679:2007: E
worldwide for CEN national Members.

Contents Page
Foreword.3
Introduction .4
1 Scope.5
2 Normative references.5
3 Terms and definitions .7
4 Symbols and abbreviations .8
5 Characteristics.8
5.1 General.8
5.2 Equilibrium moisture content.10
5.3 Dimensional stability.10
5.4 Durability : resistance to attack by fungi .10
5.5 Density.11
5.6 Mechanical properties.11
5.6.1 Bending strength and modulus of elasticity.11
5.6.2 Impact strength.11
5.6.3 Surface hardness.11
5.6.4 Tension perpendicular to grain.11
5.6.5 Compression strength.12
5.6.6 Strength of mechanical fasteners.12
5.7 Thermal conductivity.12
5.8 Adhesive bonding of TMT.12
5.9 Adhesion of coating to TMT .12
5.10 Emissions.12
5.11 Reaction to fire.12
5.12 Durability : resistance to attack by insects.12
5.13 Colour.12
6 Assessment of characteristics.13
6.1 General.13
6.2 Sampling.13
6.3 Factory production control.13
6.3.1 General.13
6.3.2 Characteristics of the TMT product to be controlled.14
7 Marking.15
Annex A (informative) Examples of characteristics .16
A.1 Equilibrium moisture content.16
A.2 Dimensional stability.16
A.3 Biological durability.17
Bibliography .18

Foreword
This document (CEN/TS 15679:2007) has been prepared by Technical Committee CEN/TC 175 “Round and
sawn timber”, the secretariat of which is held by AFNOR.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Introduction
The principal changes on thermal modification of timber - compared with untreated wood – are improved
dimensional stability and increased resistance to decay by wood destroying fungi, and in some cases changed
colours.
Due to the treatment, equilibrium moisture content of thermally modified timber is reduced.
Because of altered strength properties comparing to untreated wood, for the use of TMT, it is essential that
the relevant requirements of European and national Standards be taken into consideration.
Thermal modification may have an influence on reaction to fire properties of timber.
The properties of thermally modified timber and the degree that the property changes is dependent of the
wood species, the type of technology and the process parameters, particularly the treatment temperature
level.
The altering of acoustic properties can be of interest particularly for musical instruments.
Some tests have shown an increased resistance of TMT against some insects. Improved resistance against
termites has not been proved. Requirements on resistance against termites in some EU member states are to
be taken into consideration.
The technologies for manufacturing thermally modified timber are mainly characterized by the way they
reduce the oxygen concentration during treatment. The currently applied, industrial scale processes are using
atmospheres of heated air and or steam or heated nitrogen or in a bath of heated oil.
1 Scope
This Technical Specification gives definitions and characteristics for Thermally Modified Timber. TMT is used
in interior (dry, humid) and exterior conditions.
NOTE 1 TMT is usually a semi-finished product; applications are e.g. flooring, panelling, cladding, decking, windows,
doors, furniture and other internal and external joinery. Where product standard exist, the given requirements and test
methods are to be taken into consideration.

NOTE 2 Use in load bearing applications – reference to relevant EN standards should be made.

2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 20-2, Wood preservative – Determination of the protective effectiveness against Lyctus brunneus
(Stephens) – Part 2: Application by impregnation (Laboratory method)
EN 47, Wood preservatives – Determination of the toxic values against larvae of Hylotrupes bajulus
(Linnaeus) – (Laboratory method)
EN 84, Wood preservatives – Accelerated ageing of treated wood prior to biological testing – Leaching
procedure
EN 113, Wood preservatives – Test method for determining the protective effectiveness against wood
destroying basidiomycetes – Determination of the toxic values
EN 117, Wood preservatives – Determination of toxic values against Reticulitermes species (European
termites) (Laboratory method)
EN 204, Classification of thermoplastic wood adhesives for non-structural applications
EN 252, Field test method for determining the relative protective effectiveness of a wood preservative in
ground contact
EN 275, Wood preservatives – Determination of the protective effectiveness against marine borers
EN 301, Adhesives, phenolic and aminoplastic, for load-bearing timber structures – Classification and
performance requirements
EN 335-1, Durability of wood and wood-based products – Definition of use classes – Part 1: General

EN 335-2, Durability of wood and wood-based products – Definition of use classes – Part 2 : Application to
solid wood,
EN 350-1, Durability of wood and wood-based products – Natural durability of solid wood – Part 1: Guide to
the principles of testing and classification of the natural durability of wood
EN 383, Timber Structures – Test methods – Determination of embedment strength and foundation values for
dowel type fasteners
EN 408, Timber structures – Structural timber and glued laminated timber – Determination of some physical
and mechanical properties
EN 460, Durability of wood and wood-based products – Natural durability of solid wood – Guide to the
durability requirements for wood to be used in hazard classes
ENV 807, Wood preservatives – Determination of the effectiveness against soft rotting micro-fungi and other
soil inhabiting micro-organisms
prCEN/TS 839, Wood preservatives – Determination of the protective effectiveness against wood destroying
basidiomycetes - Application by surface treatment.
EN 844-1, Round and sawn timber – Terminology – Part 1 : General terms common to round timber and sawn
timber
EN 844-2, Round and sawn timber – Terminology – Part 2 : General terms relating to round timber
EN 844-3, Round and sawn timber – Terminology – Part 3 : General terms relating to sawn timber
EN 844-4, Round and sawn timber – Terminology – Part 4 : Terms relating to moisture content
EN 844-5, Round and sawn timber – Terminology – Part 5 : Terms relating to dimensions of round timber
EN 844-6, Round and sawn timber – Terminology – Part 6 : Terms relating to dimensions of sawn timber
EN 844-7 Round and sawn timber – Terminology – Part 7: Terms relating to anatomical structure of timber
EN 844-8, Round and sawn timber – Terminology – Part 8 : Terms relating to features of round timber
EN 844-9, Round and sawn timber – Terminology – Part 9 : Terms relating to features of sawn timber
EN 844-10, Round and sawn timber – Terminology – Part 10 : Terms relating to stain and fungal attack
EN 844-11, Round and sawn timber – Terminology – Part 11 : Terms relati
...