ISO 8144-1:2026

Thermal insulation — Mineral wool mats for ventilated spaces — Part 1: Specification for applications with restricted ventilation

This document specifies the properties and acceptable tolerances for bonded man-made mineral wool thermal insulating mats (batts and rolls). The mats specified in this document are for use within ventilated spaces of buildings where the essential ventilation of the space can be restricted if the thickness recovery of the insulation is excessive. See ISO 9774:2004, Figure 1, for typical locations. They can be supplied flat, folded, or in the form of a roll. This document specifies the properties to be declared by the manufacturer at the time of delivery, as well as some test methods for the determination of these properties. This document provides limiting values for most of the properties. These limiting values are for specification purposes only. Mats can be supplied with a factory-applied facing, but facings are not covered by this document. Because mats are not generally designed to support any applied load, only the mechanical properties required for adequate handling during application are specified.

Isolation thermique — Feutres en laine minérale pour sous-toitures ventilées — Partie 1: Spécifications pour application dans des conditions de ventilation restreinte

General Information

• Status: Published
• Publication Date: 28-Jan-2026
• ICS: 91.100.60 - Thermal and sound insulating materials
• Technical Committee: ISO/TC 163/SC 3 - Thermal insulation products, components and systems
• Drafting Committee: ISO/TC 163/SC 3 - Thermal insulation products, components and systems
• Current Stage: 6060 - International Standard published
• Start Date: 29-Jan-2026
• Due Date: 10-Jan-2026
• Completion Date: 29-Jan-2026

Relations

• Revises: ISO 8144-1:1995 - Thermal insulation — Mineral wool mats for ventilated roof spaces — Part 1: Specification for applications with restricted ventilation
• Effective Date: 24-Sep-2022

Overview

ISO 8144-1:2026 specifies the properties and tolerances for bonded man-made mineral wool thermal insulating mats (batts and rolls) used in ventilated spaces of buildings, especially where restricted ventilation may occur. This standard ensures that insulation materials used in such applications meet stringent criteria for quality, performance, and dimensional stability. It establishes the requirements that manufacturers must declare at the time of delivery, including guidance for properties testing and marking. The document does not cover facings, load-bearing applications, or mats designed to support applied loads.

Key Topics

• Product Types: The standard applies to mineral wool mats supplied as flat batts, folded, or in roll form.
• Dimensional and Physical Properties:
  • Requirements for nominal length, width, thickness, and squareness measured according to referenced ISO methods.
  • Strict dimensional tolerances to ensure reliable installation and performance.
• Thermal Performance:
  • Thermal resistance (R-value) and thermal conductivity (λ-value) must be declared, based on specific ISO measurement methods and under specified temperatures.
  • Limiting values are provided for specification and conformity purposes.
• Fire Behaviour:
  • Manufacturers must declare the fire behaviour of the insulation, compliant with local regulations.
• Handling Properties:
  • Products must have adequate strength for transport, handling, and installation as tested via defined procedures.
• General Product Quality:
  • Mats must be free from coarse materials, not promote mould growth, not emit odours, and must not accelerate corrosion or release dangerous substances during use.
• Marking and Traceability:
  • Insulation products must be clearly marked with key identifiers such as manufacturer, designation, dimensions, declared thermal values, and reference to ISO 8144-1:2026.

Applications

ISO 8144-1:2026 is highly relevant for manufacturers, designers, and builders involved in the construction and renovation of buildings requiring robust thermal insulation within ventilated or semi-ventilated cavities, such as:

• Attics, crawl spaces, and ventilated roof spaces where air movement may be restricted.
• Installations where maintaining dimensional stability and appropriate thickness recovery is critical to ensuring both insulation performance and necessary ventilation.
• Building projects subject to local or international compliance requirements for thermal insulation materials.
• Quality assurance programs and factory production control for mineral wool products used in building envelopes.

By adhering to ISO 8144-1:2026, stakeholders ensure they are using and specifying mineral wool insulation products that meet internationally recognized standards for thermal performance, durability, and safety.

Related Standards

For best results, ISO 8144-1:2026 should be applied with awareness of other relevant standards in thermal insulation and testing, including:

• ISO 9774:2004: Guidelines for selecting thermal insulation properties for building applications.
• ISO 7345: Definitions for physical quantities related to thermal performance of buildings.
• ISO 8301 & ISO 8302: Test methods for determining steady-state thermal resistance and related properties.
• ISO 9229: Vocabulary for thermal insulation.
• ISO 12491: Statistical methods for quality control of building materials and components.
• ISO 12576-1: Conformity control systems for factory-made insulation products.
• ISO 29465, ISO 29466, and ISO 29467: Methods for determining the length, width, thickness, and squareness of insulating products.
• ISO 10456: Procedures for determining and converting declared and design hygrothermal values.

Aligning with ISO 8144-1:2026 ensures that mineral wool insulation for ventilated spaces is consistent, high-quality, and suitable for modern building performance requirements.

Standards Content (Sample)

International
Standard
ISO 8144-1
Second edition
Thermal insulation — Mineral wool
2026-01
mats for ventilated spaces —
Part 1:
Specification for applications with
restricted ventilation
Isolation thermique — Feutres en laine minérale pour sous-
toitures ventilées —
Partie 1: Spécifications pour application dans des conditions de
ventilation restreinte
Reference number
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Sampling and conformity control . 2
5 Required properties. 2
5.1 Dimensions .2
5.2 Fire behaviour .2
5.3 Thermal resistance and thermal conductivity .3
5.4 Handling properties .4
5.5 General properties .4
6 Marking . . 4
7 Test report . 5
Annex A (normative) Determination of handling properties of mats (batts or rolls). 6
Annex B (normative) Determination of the declared values of thermal resistance and thermal
conductivity . 9
Bibliography .12

iii
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,
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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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, 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 www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 163, Thermal performance and energy use in
the built environment, Subcommittee SC 3, Thermal insulation products, components and systems.
This second edition cancels and replaces the first edition (ISO 8144-1:1995), which has been technically
revised.
The main changes are as follows:
— reference added to dimensional testing;
— revision of testing procedure for thermal conductivity and thermal resistance.
A list of all parts in the ISO 8144 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
International Standard ISO 8144-1:2026(en)
Thermal insulation — Mineral wool mats for ventilated
spaces —
Part 1:
Specification for applications with restricted ventilation
1 Scope
This document specifies the properties and acceptable tolerances for bonded man-made mineral wool
thermal insulating mats (batts and rolls). The mats specified in this document are for use within ventilated
spaces of buildings where the essential ventilation of the space can be restricted if the thickness recovery
of the insulation is excessive. See ISO 9774:2004, Figure 1, for typical locations. They can be supplied flat,
folded, or in the form of a roll.
This document specifies the properties to be declared by the manufacturer at the time of delivery, as well
as some test methods for the determination of these properties. This document provides limiting values for
most of the properties. These limiting values are for specification purposes only.
Mats can be supplied with a factory-applied facing, but facings are not covered by this document. Because
mats are not generally designed to support any applied load, only the mechanical properties required for
adequate handling during application are specified.
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 7345, Thermal performance of buildings and building components — Physical quantities and definitions
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 9229, Thermal insulation — Vocabulary
ISO 12491, Statistical methods for quality control of building materials and components
ISO 12576-1, Thermal insulation — Insulating materials and products for buildings — Conformity control
systems — Part 1: Factory-made products
ISO 29465, Thermal insulating products for building applications — Determination of length and width
ISO 29466, Thermal insulating products for building applications — Determination of thickness
ISO 29467, Thermal insulating products for building applications — Determination of squareness
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9229 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
mineral wool
fibrous thermal insulation material manufactured from molten rock, slag, or glass
3.2
mat
flexible fibrous insulation supplied in the form of rolls or batts, which may be faced but not enclosed
3.3
batt
portion of an insulation mat in the form of a rectangular piece, between 1 m and 3 m in length and supplied
flat or folded
3.4
roll
insulation product supplied in the form of a wound cylinder
4 Sampling and conformity control
Conformity control shall be in accordance with ISO 12576-1. Manufacturer shall declare which option they
have chosen.
Essentially, mats do not change their properties and are dimensionally stable for the temperature and
humidity conditions within a ventilated space.
Design values can be derived from the limiting values provided by this document by considering the
environmental factors affecting the thermal performance of the product, the influence of the product
properties on installation, and the effect of workmanship on the thermal performance. For converting
declared R- or λ-values to design values, see ISO 10456.
5 Required properties
5.1 Dimensions
The manufacturer shall declare the nominal length, width, and thickness of the mats.
These dimensions shall be measured in accordance with ISO 29465 (length and width), ISO 29466 (thickness)
and ISO 29467 (squareness) and shall be subject to the tolerance classes detailed in Table 1.
5.2 Fire behaviour
The fire behaviour of the insulation materials, including any facings, shall be declared in compliance to the
fire regulations and codes that apply in the locality in which they are applied.

Table 1 — Dimensional tolerances
Dimension Permissible deviations of Tolerance Tolerance Tolerance Test method
measured values from nom- Class A Class B Class C
inal dimensions
Length, l - 2 %, + excess permitted on ISO 29465
average of measured values
for each single specimen
Width, b ±1,5 % or ±10 mm, whichever ISO 29465
is less, on average of meas-
ured values for each single
specimen
Thickness, d For any single specimen, the -5 % or -5 mm -3 % or -3 mm -3 % or -3 mm ISO 29466
measured thickness at each whichever gives whichever gives whichever gives
individual measuring point the greatest the greatest the greatest
shall not deviate by more numerical tol- numerical tol- numerical tol-
than 10 mm from the mean erance erance erance
of measurements on that
+15 % or +10 % or +5 % or +5 mm
specimen. Refer to
...