SIST EN 301:2023+A1:2026

SLOVENSKI STANDARD
01-julij-2026
Lepila na osnovi fenolov in aminoplastov za nosilne lesene konstrukcije -
Razvrstitev in zahteve za delovanje (vključno z dopolnilom A1)
Adhesives, phenolic and aminoplastic, for load-bearing timber structures - Classification
and performance requirements
Klebstoffe, Phenoplaste und Aminoplaste, für tragende Holzbauteile - Klassifizierung und
Leistungsanforderungen
Adhésifs de nature phénolique et aminoplaste, pour structures portantes en bois -
Classification et exigences de performance
Ta slovenski standard je istoveten z: EN 301:2023+A1:2026
ICS:
83.180 Lepila Adhesives
91.080.20 Lesene konstrukcije Timber structures
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 301:2023+A1
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2026
EUROPÄISCHE NORM
ICS 83.180
English Version
Adhesives, phenolic and aminoplastic, for load-bearing
timber structures - Classification and performance
requirements
Adhésifs de nature phénolique et aminoplaste, pour Klebstoffe, Phenoplaste und Aminoplaste, für tragende
structures portantes en bois - Classification et Holzbauteile - Klassifizierung und
exigences de performance Leistungsanforderungen
This European Standard was approved by CEN on 18 December 2022 and includes Amendment 1 approved by CEN on 3 April
2026.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 301:2023+A1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Classification. 7
5 Requirements . 10
5.1 General. 10
5.2 Tensile shear test . 11
5.3 Delamination test . 12
5.4 Fibre damage test . 13
5.5 Shrinkage test . 13
5.6 Static load test . 13
5.7 Type testing of separate application finger joint adhesive . 14
6 Working properties of the adhesive . 14
6.1 General. 14
6.2 Physical properties of adhesive prepared for use . 14
6.3 Use of the adhesive . 14
7 Marking and labelling . 14
Annex A (normative) Delamination test for finger joints with separate spread of adhesive
and hardener . 15
A.1 Production of the specimens . 15
A.2 Testing . 16
A.3 Expression of results . 16
Bibliography . 17

European foreword
This document (EN 301:2023+A1:2026) has been prepared by Technical Committee CEN/TC 193
“Adhesives”, the secretariat of which is held by UNE.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by December 2026, and conflicting national standards
shall be withdrawn at the latest by December 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document includes Amendment 1 approved by CEN on 3 April 2026.
This document supersedes !EN 301:2023".
The start and finish of text introduced or altered by amendment is indicated in the text by tags !".
EN 301:2023 includes the following significant technical changes with respect to EN 301:2017:
a) Table 2 — 2 mm glue line – EN 302-3 Mandatory despite pH-value – beech used in the test;
b) Table 2 — Gap filling adhesives – EN 302-8 – tested with 1 mm glue line;
c) 5.1 b) test with representative samples of preservative treated Scots pine or Silver fir, which also
covers preservative treated Norway spruce, has been added.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Introduction
This document is one of a series of standards dealing with phenolic and aminoplastic adhesives for use
with timber structures, and is published in support of product standards for load-bearing timber
structures in connection with EN 1995-1-1, Eurocode 5: Design of timber structures — Part 1-1:
General — Common rules and rules for buildings.
The series consists of:
— one standard for classification and performance requirements (EN 301);
— six test methods (EN 302-1, EN 302-2, EN 302-3, EN 302-4, EN 302-8 and Annex A of this
document) used to assess the performance of adhesives after specified heat and humidity
treatments; and
— three test methods (EN 302-5, EN 302-6 and EN 302-7) to characterize the working properties of
the adhesive.
SAFETY STATEMENT
Persons using this document should be familiar with the normal laboratory practice, if applicable. This
document cannot address all of the safety problems, if any, associated with its use. It is the
responsibility of the user to establish appropriate safety and health practices and to ensure compliance
with any regulatory conditions.
ENVIRONMENTAL STATEMENT
It is understood that some of the material permitted in this standard may have a negative
environmental impact. As technological advantages lead to acceptable alternatives for these materials,
they will be eliminated from this standard to the greatest extent possible.
At the end of the test, the user of the standard should take care to carry out an appropriate disposal of
the wastes, according to local regulations.
1 Scope
This document establishes a classification for phenolic and aminoplastic polycondensation adhesives
according to their suitability for use for load-bearing timber products in defined climatic exposure
conditions, and specifies performance requirements for such adhesives for the factory manufacture or
factory-like manufacturing conditions of load-bearing timber products only.
This document only specifies the performance of an adhesive for use in an environment corresponding
to the defined conditions.
The performance requirements of this document are applicable to the adhesive only, not to the
manufacturing timber products. This document does not cover the performance of adhesives for on-site
gluing (except for factory-like conditions) or the production of wood-based panels, except solid wood
panels, or modified and stabilized wood with considerably reduced swelling and shrinkage properties,
e.g. acetylated wood, heat treated wood and polymer impregnated wood.
This document is primarily intended for use by adhesive manufacturers and for use in timber products
bonded with adhesives, to assess or control the quality of adhesives. The requirements are applicable to
the type testing of the adhesives. Production control activities are outside the scope of this document.
Adhesives meeting the requirements of this document are adequate for use in load-bearing timber
products, provided that the bonding process has been carried out according to an appropriate product
standard.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 302-1, Adhesives for load-bearing timber structures — Test methods — Part 1: Determination of
longitudinal tensile shear strength
EN 302-2, Adhesives for load-bearing timber structures — Test methods — Part 2: Determination of
resistance to delamination
EN 302-3, Adhesives for load-bearing timber structures — Test methods — Part 3: Determination of the
effect of acid damage to wood fibres by temperature and humidity cycling on the transverse tensile
strength
EN 302-4, Adhesives for load-bearing timber structures — Test methods — Part 4: Determination of the
effects of wood shrinkage on the shear strength
EN 302-8, Adhesives for load-bearing timber structures — Test methods — Part 8: Static load test of
multiple bond line specimens in compression shear
EN 408, Timber structures — Structural timber and glued laminated timber — Determination of some
physical and mechanical properties
EN 923, Adhesives — Terms and definitions
EN 1245, Adhesives — Determination of pH
EN 12092, Adhesives — Determination of viscosity
EN 13183-2, Moisture content of a piece of sawn timber — Part 2: Estimation by electrical resistance
method
EN 13183-3, Moisture content of a piece of sawn timber — Part 3: Estimation by capacitance method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 923 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
aminoplastic resin
thermosetting synthetic resin derived from a condensation reaction of the –NH groups or –NH groups
of amines or amides with aldehydes
3.2
phenolic resin
thermosetting synthetic resin derived from a condensation reaction of a phenol with an aldehyde
3.3
polycondensation adhesive
adhesive mixture made from a resin formed by a polymerization reaction involving the elimination of
water, usually with a hardener
Note 1 to entry: Such adhesives usually also contain extenders and/or fillers.
3.4
service class 1
climatic conditions characterized by a moisture content in the materials corresponding to a
temperature of 20 °C and the relative humidity of the surrounding air only exceeding 65 % for a few
weeks per year
Note 1 to entry: In service class 1, which comprises typical indoor conditions, the average moisture content in
most softwoods will not exceed 12 %.
[SOURCE: EN 1995-1-1:2004, 2.3.1.3, modified – Indoor conditions have been added in Note 1 to entry.]
3.5
service class 2
climatic conditions characterized by a moisture content in the materials corresponding to a
temperature of 20 °C and the relative humidity of the surrounding air only exceeding 85 % for a few
weeks per year
Note 1 to entry: In service class 2, to which most covered exterior conditions belong, the average moisture
content in most softwoods will not exceed 20 %.
[SOURCE: EN 1995-1-1:2004, 2.3.1.3 modified – Covered exterior conditions have been added in
Note 1 to entry.]
3.6
service class 3
climatic conditions leading to higher moisture contents than in service class 2
Note 1 to entry: Exterior conditions typically belong to service class 3.
[SOURCE: EN 1995-1-1:2004, 2.3.1.3, modified – Note 1 to entry has been added.]
3.7
glue line
adhesive layer between the wood members
3.8
thick glue line
glue line of nominal thickness in the range of 0,3 mm to 2,0 mm at the time of bonding
Note 1 to entry: Thick glue lines are achieved by using spacers, grooves or similar devices when two plain
members are glued together.
3.9
close contact glue line
glue line of thickness maximum 0,1 mm
Note 1 to entry: Close contact glue line can be achieved by pressing together two plane wood members with a
clamping pressure of (0,8 ± 0,1) N/mm without additional grooves, spacers or similar devices.
4 Classification
Adhesives (General purpose, Finger jointing or Gap filling) for structural purposes shall produce joints
of such strength and durability that the integrity of the bond is maintained in the assigned service class
throughout the expected life of the structure.
Two types of adhesive, I and II, are classified according to their suitability for use in different climatic
conditions:
— Type Ι to be used in service classes 1, 2 and 3.
— Type ΙΙ to be used in service class 1 only.
These two types of adhesive are further divided into three application area according to the end use:
— General-purpose adhesive (GP) to be used for glue lines between laminations, for finger joints in
laminations and structural timber, and for large finger joints;
— Finger jointing adhesive (FJ) to be used for finger jointing of laminations and structural timber
only;
— Gap filling adhesive (GF) to be used for fibre parallel gluing, e.g. glue lines between glulam
components of block-glued glulam and for large finger joints. Gap filling adhesives are in addition
classified as application area GP and FJ in mixed application without further testing.
NOTE The definition of “General purpose” and “Type” can be different in other standards.
Table 1 specifies the thirteen adhesive classes for which this document is applicable to and their
designation codes. The designation code consist of:
— type: Ι or ΙΙ;
— application: GP, FJ or GF;
— maximum test temperature in degrees Celsius: 70 or 90 for type Ι, or maximum use temperature in
degrees Celsius: 50 for type ΙΙ;
— use: M for mixed application, and S for separate application of adhesive and hardener.
All application areas and use shall be part of the designation code.
EXAMPLE Designation code EN 301 I 70 GP 0,6M and designation code EN 301 I 70 FJ 0,1S, if classified as
general purpose adhesive for mixed application and classified as finger joint adhesive for separate application.
Table 1 — Adhesive classes
Adhesive class
Max. glue line
Max. test Service
thickness
Application area
c a
temp. classes
(Designation code)
Test Use
°C mm mm
Face lamination and
finger jointing for general
use
General purpose 70 1,0 0,6 1,2,3
EN 301 I 70 GP 0,6M
General purpose 70 1,0 0,3 1,2,3
EN 301 I 70 GP 0,3S
Special use
Gap filling 90 2,0 1,5 1, 2, 3
EN 301 I 90 GF 1,5M
General purpose 90 1,0 0,6 1, 2, 3
EN 301 I 90 GP 0,6M
General purpose 90 1,0 0,3 1, 2, 3
EN 301 I 90 GP 0,3S
Finger joint 90 0,3 0,1 1, 2, 3
EN 301 I 90 FJ 0,1M
Finger joint 90 0,3 0,1 1, 2, 3
EN 301 I 90 FJ 0,1S
Finger joint 70 0,3 0,1 1, 2, 3
EN 301 I 70 FJ 0,1M
Finger joint 70 0,3 0,1 1, 2, 3
EN 301 I 70 FJ 0,1S
b
General purpose 1,0 0,6 1
EN 301 II 50 GP
...