ISO 4898:2006

INTERNATIONAL ISO
STANDARD 4898
Third edition
2006-04-15

Rigid cellular plastics — Thermal
insulation products for buildings —
Specifications
Plastiques alvéolaires rigides — Produits d'isolation thermique pour
bâtiments — Spécifications




Reference number
ISO 4898:2006(E)
©
ISO 2006

---------------------- Page: 1 ----------------------
ISO 4898:2006(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.


©  ISO 2006
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland

ii © ISO 2006 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 4898:2006(E)
Contents Page
Foreword. iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Sizes and dimensional-tolerance requirements . 3
5 Physical-property requirements. 4
5.1 Categories . 4
5.2 Subcategories . 4
5.3 Limiting quality values . 4
5.4 Burning characteristics. 4
6 Sampling. 4
7 Ageing and conditioning. 5
7.1 Ageing. 5
7.2 Conditioning. 5
8 Test methods. 5
8.1 Linear dimensions . 5
8.2 Density . 5
8.3 Compressive strength. 5
8.4 Thermal conductivity. 6
8.5 Dimensional stability/compressive creep properties at elevated temperature. 6
8.6 Water vapour permeability. 6
8.7 Water absorption . 6
8.8 Bending load at break . 7
9 Conformity control. 7
10 Labelling and marking of products. 7
11 Reporting requirements . 7
Annex A (normative) Amendments to ISO 12576-1 . 12
Bibliography . 14

© ISO 2006 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO 4898:2006(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 4898 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 10, Cellular plastics.
This third edition cancels and replaces the second edition (ISO 4898:2004), which has been technically
revised.

iv © ISO 2006 – All rights reserved

---------------------- Page: 4 ----------------------
INTERNATIONAL STANDARD ISO 4898:2006(E)

Rigid cellular plastics — Thermal insulation products for
buildings — Specifications
1 Scope
This International Standard specifies requirements and methods of testing for four categories of rigid cellular
plastics thermal-insulation products for buildings. It covers rigid cellular plastics in the form of flat or profiled
boards, with or without natural skins. They may also be faced or laminated with foil, plastic or metal films or
sheets, mineral coatings, paper, cardboard or other materials.
This International Standard is not applicable to materials used for the thermal insulation of pipes and vessels,
for impact sound absorption or for acoustical insulation.
This International Standard covers the following cellular materials used in the thermal insulation of buildings:
PF based on phenolic polymer;
EPS based on expanded polystyrene;
XPS based on extruded polystyrene;
PUR based on polyurethane.
The limiting quality values in this International Standard are for use only in the specification of materials
between purchaser and supplier, and are not intended to be used for design purposes.
Additional requirements for special applications may be added to those specified in this International Standard
by agreement between purchaser and supplier.
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.
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 472, Plastics — Vocabulary
ISO 844, Rigid cellular plastics — Determination of compression properties
ISO 845, Cellular plastics and rubbers — Determination of apparent density
ISO 1040, Building construction — Modular coordination — Multimodules for horizontal coordinating
dimensions
ISO 1209-1, Rigid cellular plastics — Determination of flexural properties — Part 1: Basic bending test
ISO 1663, Rigid cellular plastics — Determination of water vapour transmission properties
© ISO 2006 – All rights reserved 1

---------------------- Page: 5 ----------------------
ISO 4898:2006(E)
ISO 1923, Cellular plastics and rubbers — Determination of linear dimensions
ISO 2796, Cellular plastics, rigid — Test for dimensional stability
ISO 2896, Rigid cellular plastics — Determination of water absorption
ISO 7616, Cellular plastics, rigid — Determination of compressive creep under specified load and temperature
conditions
ISO 7850, Cellular plastics, rigid — Determination of compressive creep
ISO 8301, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Heat flow meter apparatus
ISO 8302, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Guarded hot plate apparatus
ISO 11561:1999, Ageing of thermal insulating materials — Determination of the long-term change in thermal
resistance of closed-cell plastics (accelerated laboratory test methods)
ISO 12576-1:2001, Thermal insulation — Insulating materials and products for buildings — Conformity control
systems — Part 1: Factory-made products
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
EPS
rigid cellular plastic material manufactured by moulding beads of expandable polystyrene or one of its
copolymers and which has a substantially closed cell structure, filled with air
[ISO 9229:—]
3.2
XPS
rigid cellular plastic insulation material expanded and extruded with or without a skin from polystyrene or one
of its copolymers and which has a closed cell structure
[ISO 9229:—]
3.3
PUR
rigid cellular plastic insulation material with a substantially closed cell structure based on polyurethane or
urethane/isocyanurate polymers
NOTE For definitions of polyisocyanurate plastic, polyurethane and urethane plastic, see ISO 472.
3.4
PF
rigid cellular foam, the polymer structure of which is made primarily from the polycondensation of phenol, its
homologues and/or derivatives with aldehydes or ketones
[ISO 9229:—]
NOTE PF used for thermal-insulation purposes has a cellular structure consisting substantially of closed cells
(subcategory A) or with a higher content of open cells (subcategory B) which affects the thermal conductivity.
2 © ISO 2006 – All rights reserved

---------------------- Page: 6 ----------------------
ISO 4898:2006(E)
4 Sizes and dimensional-tolerance requirements
4.1 Board materials shall be supplied in dimensions agreed between purchaser and supplier or in
accordance with ISO 1040. Boards shall be flat.
4.2 Dimensional tolerances for length, width and squareness shall conform to the requirements specified in
Table 1.
Table 1 — Tolerances for dimensions and squareness
Squareness tolerances
Tolerance on length or width based on differences in
Length or width
(see Note 1) diagonal measurements
(see Notes 2 and 3)
mm mm mm
5
< 1 000 ± 8
W 1 000 5
± 10
NOTE 1 If more restrictive tolerances are required, these shall be agreed between purchaser and supplier.
NOTE 2 Tolerance categories for diagonal measurements are based on the board length (not width).
NOTE 3 Squareness may also be determined by equivalent methods such as the use of a rectangular pattern.

4.3 Dimensional tolerances for thickness shall conform to the requirements specified in Table 2.
Table 2 — Tolerances for thickness
Thickness Tolerance (see Note 1)
mm mm
less than 50
± 2
50 to 75 (incl.) ± 3
> 75 to 100 (incl.) ± 3 (see Note 2)
To be agreed between purchaser and supplier
> 100
NOTE 1 If more restrictive tolerances are required, these shall be agreed between purchaser and supplier.
NOTE 2 For EPS with natural skins, the thickness tolerance for this thickness category shall be ± 4 mm.

© ISO 2006 – All rights reserved 3

---------------------- Page: 7 ----------------------
ISO 4898:2006(E)
5 Physical-property requirements
5.1 Categories
Physical-property requirements are organized into product categories to meet purchaser and supplier needs
over a range of end-use applications.
Category I Suitable for non-load-bearing applications such as wall and cavity insulation, vented roofs, cavity
wall insulation and similar applications.
Category II Suitable for limited load-bearing applications such as in built-up roofs, under floors and
comparable applications, where elevated temperatures may be encountered and where compressive creep
resistance is required. Products in this category may also be used for applications listed in category I.
Categories III and IV Suitable for load-bearing applications such as in parking decks, floors of cold-storage
areas and comparable applications requiring a higher level of compressive strength and compressive creep
resistance. Products in these categories may also be used for applications listed in categories I and II.
5.2 Subcategories
Product property categories I to III can be further divided into subcategories (A, B, C) on the basis of thermal-
conductivity values. All thermal-conductivity specification values given for the subcategories in the tables are
maximum values.
Thermal-conductivity values given in the tables shall be used only as limiting quality values for specification of
materials between purchaser and supplier. They shall not be used for design purposes.
5.3 Limiting quality values
EPS materials shall conform to the limiting quality values for physical properties as specified in Table 3.
XPS materials shall conform to the limiting quality values for physical properties as specified in Table 4.
PUR materials shall conform to the limiting quality values for physical properties as specified in Table 5.
PF materials shall conform to the limiting quality values for physical properties as specified in Table 6.
5.4 Burning characteristics
It is recognized that there is a need to consider the burning characteristics of these materials in their intended
application. Therefore, until such time as International Standards become available, individual national
practice should be followed.
NOTE Due to compositional and processing parameters, some PF materials may exhibit smouldering combustion
(punking).
6 Sampling
6.1 For density determinations, ten full-size boards are required.
6.2 For all other physical-property determinations and for dimensional measurements, at least three full-size
boards are required.
4 © ISO 2006 – All rights reserved

---------------------- Page: 8 ----------------------
ISO 4898:2006(E)
7 Ageing and conditioning
7.1 Ageing
7.1.1 There is no requirement to age materials faced with impermeable, hole-free facings.
NOTE For example, metal coverings of about 50 µm thickness have been found to meet this facing requirement.
7.1.2 All materials without impermeable, hole-free facings shall be aged un
...