ISO 27769:2016

INTERNATIONAL ISO
STANDARD 27769
First edition
2016-12-15
Wood-based panels — Wet process
fibreboard
Panneaux à base de bois — Panneau de fibres obtenu par procédé
humide
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
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ii © ISO 2016 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Classifications, designation and coding . 2
5.1 General . 2
5.1.1 Classification matrices . 2
5.1.2 Structural grades . 3
5.2 Softboards . 3
5.3 Hardboards . 3
6 Mandatory tests relating to each grade . 4
6.1 General . 4
6.2 Softboards . 4
6.3 Hardboards . 4
6.4 Supplementary properties . 4
7 Thickness ranges . 5
7.1 Specification values . 5
7.2 Softboards . 5
7.3 Hardboards . 5
8 Expression of specification limits and general requirements . 5
8.1 Expression of specification limits . 5
8.2 Lower specification limits . 6
8.3 Upper specification limits. 6
8.4 Density variation, dimension and moisture content requirements . 6
9 Requirements for softboards . 7
9.1 Requirements for general purpose softboard for use in dry conditions . 7
9.2 Requirements for general purpose softboard for use in humid conditions . 7
9.3 Requirements for general purpose softboard for use in high-humidity conditions . 7
9.4 Requirements for general purpose softboard for use in exterior conditions . 7
9.5 Requirements for load-bearing softboard for use in dry conditions . 8
9.6 Requirements for load-bearing softboard for use in humid conditions . 8
10 Requirements for hardboards . 8
10.1 Requirements for general purpose hardboard for use in dry conditions . 8
10.2 Requirements for general purpose hardboard for use in humid conditions . 9
10.3 Requirements for general purpose hardboard for use in high-humidity conditions . 9
10.4 Requirements for general purpose hardboard for use in exterior conditions . 9
10.5 Requirements for load-bearing hardboard for use in dry conditions .10
10.6 Requirements for load-bearing hardboard for use in humid conditions .10
Annex A (normative) Calculation of 5-percentile and 95-percentile values .12
Bibliography .14
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 89, Wood-based panels, Subcommittee SC 01,
Fibre boards.
This first edition cancels and replaces ISO 27769-1:2009 and ISO 27769-2:2009, which have been
technically revised.
iv © ISO 2016 – All rights reserved

INTERNATIONAL STANDARD ISO 27769:2016(E)
Wood-based panels — Wet process fibreboard
1 Scope
This document provides a classification matrix and related mandatory tests for two types of wet process
fibreboard made from wood: softboards and hardboards and specifies the relevant manufacturing
property requirements.
NOTE 1 Wet process fibreboards are divided into three types: softboards, medium boards and hardboards.
This document is not applicable to medium boards.
NOTE 2 Fibreboards are broadly divided into two groups based on the manufacturing process, namely the
dry-process group and the wet process group. This document is not applicable to dry-process fibreboards (see
ISO 16895).
NOTE 3 The values listed in this document relate to product properties used to classify fibreboards into one
of the different types. The values are not characteristic values to be used for design purposes. When fibreboard
is classified as load-bearing and nominated for structural applications, characteristic strength and stiffness
values are established based upon testing in accordance with ISO 16572 or equivalent ASTM or EN Standards.
Alternatively, for specific load-bearing applications (e.g. walls, roofs, floors and I-joist webs), the load-bearing
fibreboard would meet the specific performance requirements for that intended application.
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.
ISO 3340, Fibre building boards — Determination of sand content
ISO 9426, Wood-based panels — Determination of dimensions of panels
ISO 9427, Wood-based panels — Determination of density
ISO 16978, Wood-based panels — Determination of modulus of elasticity in bending and of bending strength
ISO 16979, Wood-based panels — Determination of moisture content
ISO 16981, Wood-based panels — Determination of surface soundness
ISO 16983, Wood-based panels — Determination of swelling in thickness after immersion in water
ISO 16984, Wood-based panels — Determination of tensile strength perpendicular to the plane of the panel
ISO 16985, Wood-based panels — Determination of dimensional changes associated with changes in
relative humidity
ISO 16998, Wood-based panels — Determination of moisture resistance — Boil test
ISO 20585, Wood-based panels — Determination of wet bending strength after immersion in water at 70 °C
or 100 °C (boiling temperature)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 17064 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
wet process fibreboard
wood fibreboard with a forming line moisture content of greater than 20 % and whose primary bonding
results from the felting of the wood fibres and their inherent adhesive properties
Note 1 to entry: According to the density, the types of fibreboard are the following:
a)  softboards, of density <400 kg/m ;
3 3
b)  medium boards, of density ≥400 kg/m to <840 kg/m ;
c)  hardboards, of density ≥800 kg/m .
Note 2 to entry: Tables for the classification of medium boards are not included in this document. They can be
included as they become available on the international market.
Note 3 to entry: Density ranges given in product descriptions in 5.2 and 5.3 are a guide. Manufacturers can
classify a product as a particular type if the product is within 20 % of the nominated density range and if it has
all of the properties of the nominated type.
4 Abbreviated terms
The following abbreviated terms are used in the preparation of the classification matrices:
REG regular for use in dry conditions only
MR moisture resistant for use in humid conditions
HMR high moisture resistant for use in high-humidity conditions
EXT exterior for exterior use above ground
LB load-bearing for structural or load-bearing use
GP general purpose for use in general applications and furniture, not requiring the
specific properties of load-bearing grades
DIY do-it-yourself for use in home projects, rather than by professional tradespersons
NOTE For definitions of the terms dry, humid, high humid, load-bearing and structural, see ISO 17064.
5 Classifications, designation and coding
5.1 General
5.1.1 Classification matrices
Overall classification matrices, which include all major classes available at the time of publication, are
given in Table 1 for softboards and in Table 2 for hardboards.
2 © ISO 2016 – All rights reserved

5.1.2 Structural grades
When a product is used in a complex load-bearing or structural application, additional information
shall be available in the form of characteristic values derived from structural testing (see ISO 16572),
experimental test results or history of use to validate its performance under the proposed conditions.
5.2 Softboards
An overall classification matrix, which includes all major classes available at the time of publication,
is shown in Table 1. Table 1 allows for future grades to be included as they become available on the
international markets.
Table 1 — Classification matrix for softboards
Conditions of use
Softboard type
Dry, regular Humid High humid Exterior
REG MR HMR EXT
SB-GP General purpose General purpose General purpose General purpose
softboard softboard softboard softboard
Application Partitions, acoustic,
Partitions, acoustic Advertising Joints
examples rigid underlays
MR load-bearing
SB-LB No existing product No existing product No existing product
softboard
Application
Rigid underlays
examples
Additional attributes such as fire retardant (FR), insect retardant (I) and fungi retardant (F), may be added to the softboard
classification of Table 1.
5.3 Hardboards
An overall classification matrix, which includes all major classes ava
...