prEN 14024

Metal profiles with thermal barrier - Mechanical performance - Requirements, proof and tests for assessment

This document specifies requirements for assessment of the mechanical strength of metal profiles incorporating a thermal barrier having mechanical performance depending on their intended use.
It also specifies the tests to determine the characteristic values of mechanical properties of the thermal barrier profile and to assess the effect of different conditionings of the thermal barrier on the mechanical performance of the connection.
This document does not apply to thermal barriers which do not give a contribution to the mechanical resistance of the profiles.
This document is applicable to thermal barrier profiles designed mainly for windows, doors, screens and curtain walls.
This document does not apply to thermal barriers made only of metal profiles connected with metal pins or screws.
NOTE   This current edition of EN 14024 will supersede EN 14024:2004. Differences in test procedures between the two versions will not lead to significant differences in test results. Therefore, existing test results according to EN 14024:2004 shall be considered as equivalent to new test results according to the current edition of EN 14024.

Metallprofile mit thermischer Trennung - Mechanisches Leistungsverhalten - Anforderungen, Nachweis und Prüfungen für die Beurteilung

In diesem Dokument sind die Anforderungen an die Beurteilung der mechanischen Festigkeit von Metallprofilen mit thermischer Trennung festgelegt, die in Abhängigkeit von ihrem bestimmungsgemäßen Gebrauch eine unterschiedliche Beurteilung ihres mechanischen Leistungsverhaltens erfordern.
Es legt auch die Prüfungen zur Bestimmung der charakteristischen Werte von mechanischen Eigenschaften des Metallprofils mit thermischer Trennung und die Beurteilung der Auswirkungen verschiedener Konditionierungen der thermischen Trennung auf das mechanische Leistungsverhalten der Verbindung fest.
Thermische Trennungen, die keinen Beitrag zur mechanischen Festigkeit der Profile leisten, werden in diesem Dokument nicht behandelt.
Dieses Dokument gilt für Metallprofile mit thermischer Trennung, die hauptsächlich für Fenster, Türen, zusammengesetzte Elemente und Vorhangfassaden vorgesehen sind. Es gilt nicht für thermische Trennungen, die nur aus mit Metallstiften oder Schrauben verbundenen Metallprofilen hergestellt sind.

Profilés métalliques à rupture de pont thermique - Performances mécaniques - Exigences, preuve et essais pour évaluation

Le présent document spécifie les exigences pour l’évaluation de la résistance mécanique des profilés métalliques à rupture de pont thermique présentant des performances mécaniques qui dépendent de l’utilisation prévue.
Il spécifie également les essais destinés à déterminer les valeurs caractéristiques des propriétés mécaniques des profilés à rupture de pont thermique et à évaluer l’effet de différentes mises en condition dans l’enceinte d’essai de la coupure thermique sur les performances mécaniques de la liaison.
Les coupures thermiques qui ne contribuent pas à la résistance mécanique des profilés sont exclues du présent document.
Le présent document s’applique aux profilés à rupture de pont thermique conçus principalement pour les fenêtres, les portes, les ensembles menuisés et les façades rideaux. Il ne s’applique pas aux coupures thermiques constituées uniquement de liaisons métalliques ponctuelles ou de vis.

Kovinski profili s prekinjenim toplotnim mostom - Mehanske lastnosti - Zahteve, izračuni in preskušanja

General Information

• Status: Not Published
• ICS: 91.060.10 - Walls. Partitions. Facades
• ICS: 91.060.50 - Doors and windows
• Technical Committee: CEN/TC 33 - Doors, windows, shutters and building hardware
• Drafting Committee: CEN/TC 33 - Doors, windows, shutters and building hardware
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 16-Dec-2022
• Due Date: 12-Apr-2022
• Completion Date: 16-Dec-2022
• Ref Project: oSIST prEN 14024:2021 - Metal profiles with thermal barrier - Mechanical performance - Requirements, proof and tests for assessment

Relations

• Revises: EN 14024:2004 - Metal profiles with thermal barrier - Mechanical performance - Requirements, proof and tests for assessment
• Effective Date: 08-Jul-2020

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 14024:2021
01-november-2021
Kovinski profili s prekinjenim toplotnim mostom - Mehanske lastnosti - Zahteve,
izračuni in preskušanja

Metal profiles with thermal barrier - Mechanical performance - Requirements, proof and

tests for assessment
Metallprofile mit thermischer Trennung - Mechanisches Leistungsverhalten -
Anforderungen, Nachweis und Prüfungen für die Beurteilung
Profilés métalliques à rupture de pont thermique - Performances mécaniques -
Exigences, preuve et essais pour évaluation
Ta slovenski standard je istoveten z: prEN 14024
ICS:
91.060.10 Stene. Predelne stene. Walls. Partitions. Facades
Fasade
91.060.50 Vrata in okna Doors and windows
oSIST prEN 14024:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 14024:2021
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oSIST prEN 14024:2021
DRAFT
EUROPEAN STANDARD
prEN 14024
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2021
ICS 91.060.10; 91.060.50 Will supersede EN 14024:2004
English Version
Metal profiles with thermal barrier - Mechanical
performance - Requirements, proof and tests for
assessment

Profilés métalliques à rupture de pont thermique - Metallprofile mit thermischer Trennung -

Performances mécaniques - Exigences, preuve et essais Mechanisches Leistungsverhalten - Anforderungen,

pour évaluation Nachweis und Prüfungen für die Beurteilung

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 33.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 14024:2021 E

worldwide for CEN national Members.
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oSIST prEN 14024:2021
prEN 14024:2021 (E)
Contents Page

European foreword ....................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 Symbols and abbreviations ...................................................................................................................... 11

5 Requirements ................................................................................................................................................ 14

5.1 General ............................................................................................................................................................. 14

5.2 Thermal barrier with mechanical functions ...................................................................................... 15

5.3 Mechanical resistance ................................................................................................................................ 16

5.4 Static proof ..................................................................................................................................................... 18

6 Tests .................................................................................................................................................................. 18

6.1 General ............................................................................................................................................................. 18

6.1.1 Test specimens .............................................................................................................................................. 18

6.1.2 Test temperature ......................................................................................................................................... 18

6.1.3 Pre-test conditioning .................................................................................................................................. 19

6.2 Effects of different conditionings of the thermal barrier on the mechanical

performances of the connection ............................................................................................................. 19

6.2.1 Generalities .................................................................................................................................................... 19

6.2.2 Performance after immersion in water ............................................................................................... 19

6.2.3 Performance after exposure to humidity ............................................................................................ 19

6.2.4 Testing for brittleness ................................................................................................................................ 20

6.2.5 Testing of the creep factor under constant shear load ................................................................... 20

6.2.6 Testing of the creep factor under constant transverse tensile load .......................................... 20

6.2.7 Performance after exposure to UV radiation (if applicable) ........................................................ 20

6.2.8 Testing for tensile cracks .......................................................................................................................... 21

6.3 Transverse tensile strength (Q) .............................................................................................................. 21

6.3.1 Test specimens .............................................................................................................................................. 21

6.3.2 Test procedure .............................................................................................................................................. 22

6.3.3 Evaluation ....................................................................................................................................................... 23

6.4 Shear strength and elasticity constant (T, c) ...................................................................................... 23

6.4.1 Test specimens .............................................................................................................................................. 23

6.4.2 Test procedure .............................................................................................................................................. 24

6.4.3 Result types of systems with mechanical design system type A ................................................. 25

6.4.4 Test flow .......................................................................................................................................................... 27

6.4.5 Special cases ................................................................................................................................................... 27

6.4.6 Evaluation ....................................................................................................................................................... 30

6.5 Ageing ............................................................................................................................................................... 30

6.5.1 General ............................................................................................................................................................. 30

6.5.2 Method 1 = M1 ............................................................................................................................................... 30

6.5.3 Method 2 = M2 ............................................................................................................................................... 32

6.5.4 Method 3 = M3 ............................................................................................................................................... 33

6.6 Characteristic values ................................................................................................................................... 34

6.6.1 Transverse tensile strength ..................................................................................................................... 34

6.6.2 Characteristic shear strength .................................................................................................................. 34

6.6.3 Elasticity constant ........................................................................................................................................ 34

6.6.4 Residual deformation Δh for M1 and deformation f for M2 ......................................................... 34

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6.6.5 Ageing effect, creep factor φ under constant shear load........................................................... 34

c,s

6.6.6 Ageing effect, creep factor φ under constant transverse tensile load .................................. 35

c,t

6.6.7 Combined shear and tensile stress, design-factor γ ................................................................... 35

6.7 Test report ...................................................................................................................................................... 35

6.7.1 General ............................................................................................................................................................. 35

6.7.2 Test report on effects of different conditionings of the thermal barrier on the

mechanical performances of the connection ...................................................................................... 35

6.7.3 Test report on the mechanical resistance of the profile ................................................................ 36

Annex A (informative) Static proof ........................................................................................................................ 38

A.1 Actions .............................................................................................................................................................. 38

A.2 Profiles without shear connection (type C)......................................................................................... 39

A.2.1 Flexural stress ................................................................................................................................................ 39

A.2.2 Transverse tensile strength ...................................................................................................................... 41

A.2.3 Deflection......................................................................................................................................................... 42

A.3 Profiles with shear connection (types A and B)................................................................................. 43

A.3.1 General ............................................................................................................................................................. 43

A.3.2 Metal profile sections .................................................................................................................................. 44

A.3.3 Shear strength of the thermal barrier ................................................................................................... 44

A.3.4 Transverse strength of the thermal barrier ....................................................................................... 45

A.3.5 Deflection......................................................................................................................................................... 45

Annex B (informative) Extrapolation of characteristic data ........................................................................ 46

B.1 General ............................................................................................................................................................. 46

B.2 Shear strength T and transverse tensile strength Q ........................................................................ 46

B.3 Elasticity constant c, creep factor φ .................................................................................................. 46

c,s

Annex C (informative) Effective momentum of inertia of thermal barrier profiles ............................ 48

Annex D (informative) Simple products which typically do not need a static proof by

calculation ....................................................................................................................................................... 50

D.1 Simple product definition .......................................................................................................................... 50

D.2 Mechanical properties ................................................................................................................................ 51

D.3 Static proof ...................................................................................................................................................... 51

Bibliography ................................................................................................................................................................. 53

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oSIST prEN 14024:2021
prEN 14024:2021 (E)
European foreword

This document (prEN 14024:2021) has been prepared by Technical Committee CEN/TC 33 “Doors,

windows, shutters, building hardware and curtain walling”, the secretariat of which is held by AFNOR.

This document is currently submitted to the CEN Enquiry.
This document will supersede EN 14024:2004.

Thermal barrier profiles are used in various fields of applications and demand a differing assessment of

their mechanical performance depending on their intended use.

This document deals with the general field of application: profiles in windows, doors and façades.

In the design process, the safety aspect is part of national competency. For this reason, the definition of

specific products that normally do not require tests or proof by calculation for the determination of

mechanical properties, is a task of national specifications. This document applies when national

specifications require tests or proof by calculation to determine the characteristic values of mechanical

properties of the thermal barrier profile and to assess the suitability of the thermal barrier material.

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oSIST prEN 14024:2021
prEN 14024:2021 (E)
1 Scope

This document specifies requirements for assessment of the mechanical strength of metal profiles

incorporating a thermal barrier having mechanical performance depending on their intended use.

It also specifies the tests to determine the characteristic values of mechanical properties of the thermal

barrier profile and to assess the effect of different conditionings of the thermal barrier on the mechanical

performance of the connection.

Thermal barriers which do not give a contribution to the mechanical resistance of the profiles are

excluded from this document.

This document applies to thermal barrier profiles designed mainly for windows, doors, screens and

curtain walls. It does not apply to thermal barriers made only of metal profiles connected with metal pins

or screws.
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 ISO 4892-2, Plastics — Methods of exposure to laboratory light sources — Part 2: Xenon-arc lamps (ISO

4892-2:2013)
EN 12519, Windows and pedestrian doors — Terminology

EN 14351-1:2006+A2:2016, Windows and doors — Product standard, performance characteristics — Part

1: Windows and external pedestrian doorsets

EN ISO 22088-4, Plastics — Determination of resistance to environmental stress cracking (ESC) — Part 4:

Ball or pin impression method (ISO 22088-4:2006)

EN 1991-1-4, Eurocode 1: Actions on structures — Part 1-4: General actions — Wind actions

prEN 16759:2019, Bonded glazing for doors, windows and curtain walling — Verification of mechanical

performance of bonding
3 Terms and definitions

For the purposes of this document, the following terms and definitions apply / the terms and definitions

given in EN 12519 and the following apply.

ISO and IEC maintain terminological 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
thermal barrier profile

profile composed of two or more metal sections connected by at least one thermally insulating (non-

metallic) part
Note 1 to entry: The thermal barrier contributes to load transmission.
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3.2
temperature categories

two temperature categories are defined and to be chosen according to the intended use (see Table 1)

Table 1 — Temperature categories and test temperature
Temperature category Low test temperature LT High test temperature HT
TC 1 (−10 ± 2) °C (70 ± 3) °C
TC 2 (−20 ± 2) °C (80 ± 3) °C
Note 1 to entry: Temperature category TC2 includes Temperature category TC1.

Note 2 to entry: When specifically required (i.e. by the local climatic conditions or for specific

application/project), voluntary tests can be carried out at adapted temperatures (LT and HT).

3.3
mechanical design systems
see Figure 1
Key
1 thermal barrier
2 metal
(a) Type A system
(b) Type B system
(c) Type C system
Figure 1 — Schematic diagram of mechanical design systems
3.3.1
Type A system

system which is designed to transfer shear and in which shear failure will not reduce significantly the

transverse tensile strength
3.3.2
Type B system

system which is designed to transfer shear and in which shear failure will negatively impair the

transverse tensile strength

Note 1 to entry: E.g.: resin or foam poured into the gap between the two metal sections and hardened only by

chemical reaction (Figure 2 a)) or flat strips of thermal barrier, only glued into the metal grooves (Figure 2 b)).

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oSIST prEN 14024:2021
prEN 14024:2021 (E)

a) b)

Figure 2 — Examples of mechanical design systems Type B
3.3.3
Type C system
system for which the shear transfer is not taken into account
3.4
geometric design types

the following classification can be applied for thermal barrier profile designed for windows, doors,

curtain walls and its secondary parts
3.4.1
Type 1 profile

profile in which the thermal barrier is symmetrically loaded (see Figure 3), e.g. thermal barrier profile

used in stick systems of curtain walls, symmetrically loaded (Figure 3 a.1))
Key
1 thermal barrier profile
2 glass pane
3 line load
4 mechanical design system type B
Figure 3 — Examples of geometric design type 1 (symmetrically loaded profile)
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oSIST prEN 14024:2021
prEN 14024:2021 (E)
3.4.2
Type 2 profile

profile whose thermal barrier is nearly symmetrically loaded, i.e. the eccentricity of the load α=a/b does

not exceed the value of 5 (see Figure 4), e.g. thermal barrier profile used in unitized systems of curtain

walls, nearly symmetrically loaded (Figure 4 c.1))
Key
1 thermal barrier profile
2 glass pane
3 line load
4 mechanical design system type B

5 connection having no mechanical performances or no thermal barrier function (excluded from this

document)

Figure 4 — Examples of geometric design type 2 (nearly symmetrical loaded profiles with

eccentricity α = a/b ≤ 5)

Note 1 to entry: 5 mm is the reasonable distance, depending on the thermal barrier profile system, between the

end of the profile and the central line of the groove (i.e. the foot of the gaskets).

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oSIST prEN 14024:2021
prEN 14024:2021 (E)
3.4.3
Type 3 profile

profile whose thermal barrier is asymmetrically loaded (see Figure 5), i.e. all profiles not covered by type

1 and type 2 with the resulting load parallel to the axis of the thermal barrier

Figure 5 — Examples of geometric design type 3 (asymmetrically loaded profiles with

eccentricity α = a/b > 5)
3.4.4
Type 4 profile

profiles in which the resulting load is not parallel to the axis of the thermal barrier (e.g. non-

symmetrically loaded profiles, see Figure 6). These geometric design types are not covered by this

standard. The test method for some of these profiles are described in prEN 16759:2019, Annex F. For

non-symmetric profiles not covered by prEN 16759, specific testing and/or a FEM analysis is required

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oSIST prEN 14024:2021
prEN 14024:2021 (E)

Figure 6 — Examples of geometric design type 4 (non-symmetrically loaded profiles)

Note 1 to entry: For type 4, it is recommended to carry out a specific test simulating the real application of the

load, since the behaviour of the profile depends on the way the profile is clamped and loaded.

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oSIST prEN 14024:2021
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4 Symbols and abbreviations

For the purposes of this document, the following symbols and abbreviations apply.

A Area of the metal section 1 [mm ]
A Area of the metal section 2 [mm ]

a Distance between: the centre of mass of metal section 1 and the centre of mass of

the composite profile [mm]

a Distance between: the centre of mass of metal section 2 and the centre of mass of

the composite profile [mm]

a Distance between: the centre of mass of metal section 1 and the centre of mass of

metal section 2 [mm]

a The lever arm of the acting moment measured from the centre line of (b) and the

centre point of the load application area [mm]
b The smallest dimension of the lever arm of the resistant moment of the thermal
barrier [mm]
c 2
Elasticity constant [N/mm ]
C Measure of the effect of the elastic connection
C Limiting design value of the relevant serviceability criterion
E 2
Module of elasticity (i.e. Young module) [N/mm ]
E Effect of the action(s)

EULS;d Design value of the effect of the action (s), expressed as calculated stress, caused by

action (s) at the ultimate limit state

ESLS;d Design value of the effect of the action (s), expressed as calculated stress, caused by

action (s) at the serviceability limit state
E{F } Calculation of the effect of the serviceability limit state design value
SLS;d
E{F } Calculation of the effect of the ultimate limit state design value
ULS;d
f Remaining deformation after artificial ageing, method 2 [mm]
F Force [N]
F Design value of the action

FSLS;d Serviceability limit state design value of a single action or of a combination of

actions.

FULS;d Ultimate limit state design value of a single action or of a combination of actions.

FEM Numerical simulation analysis
G Value of self weight load
h Height of the thermal barrier
I Moment of inertia of the metal section 1
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oSIST prEN 14024:2021
prEN 14024:2021 (E)
I Moment of inertia of the metal section 2
I 4
eff Effective moment of inertia [mm ]
I 4
s Rigid moment of inertia [mm ]
l Length of the test specimen [mm]
L Span of the framing member [mm]
PA Polyamide
PU Polyurethanes
PUR Polyurethanes
PPO Polyphenylene Oxide
Q Transverse tensile strength [N/mm]
Q Value of the single action or dominant action
k,1
Q Values of the actions which are not dominant
k,i
R Characteristic value of the resistance to the actions
R Design value of the resistance to the actions
s Standard deviation of the series under consideration
SLS Service Limit State
ULS Ultimate Limit State
T Shear strength [N/mm]
TC1 Temperature category 1
TC2 Temperature category 2
t Thickness of the metallic wall
t Thickness of the thermal barrier
w Allowable deflection
w Maximum deflection calculated for the design load
max
Δh Remaining deformation after artificial ageing, method 1 [mm]
ΔF Increase of the load [N]
ΔT Temperature differences [K]
Δδ Displacement [mm]

Parameter depending on the geometry of the profile section, the elasticity constant

c of the thermal barrier and the modulus of elasticity E of the metal and also on the

span of the framing member L
α Eccentricity of the load application, calculated as "a/b"
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oSIST prEN 14024:2021
prEN 14024:2021 (E)
Compound part of the rigid moment of inertia
φc,s Creep factor under shear load
NOTE the corresponding symbol in accordance with EN 14024:2004 was: A
φ Creep factor under transversal load
c,t
γG Partial factor for permanent, also accounting for model uncertainties and
dimensional variations
γ Partial safety factor of the material
γ Partial safety factor of the material that takes into account also the kind of
connection and not only the material property (γ )

γQ Partial factor for variable actions, also accounting for model uncertainties and

dimensional variations
γ Design factor for type B
NOTE the corresponding symbol in accordance with EN 14024:2004 was: A
σ Maximum stress calculated for the design load
max
ψ Combination factors for the actions
ψ Combination factors for the actions which are not dominant
0,i
ψ Partial factor for a frequent value of a variable action
ψ Combination factor for a quasi-permanent value of a variable action
ψ Combination factor for a quasi-permanent value of a variable action
2,i
For the purposes of this document, the following indexes apply.

c Characteristic value which has a 95 % chance of being exceeded based on a normal

distribution with 75 % confidence
d Design value
HT High temperature
LT Low temperature
M1 After artificial ageing, method 1
M2 After artificial ageing, method 2
M3 After artificial ageing, method 3
Max. Maximum
mean Mean value
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prEN 14024:2021 (E)
N New, before artificial ageing
Req. Required
RT Room temperature
5 Requirements
5.1 General

Thermal barrier profiles shall be assessed through transverse tensile and shear tests, according to testing

methods described in Clause 6. Values to be assessed for different profile types are defined in Table 2.

For assessing the shear related to the thermal barrier systems, three types A, B and C (see 3.3) shall be

distinguished.

Because of the intrinsic robustness of type A, shear and tensile strengths may be considered

independently, whereas type B requires the assessment of shear and tensile strengths together.

The transverse tensile strength of type A and type C shall be determined after shear failure. For type C

only the transverse tensile strength shall be determined, no shear strength and elasticity constant will be

given.

This document doesn’t cover thermal barrier supporting permanent loads except the following ones:

a) the transversal tensile load created by conventional gaskets and glazing seals;

b) for the type A and B mechanical designs, the vertical shear load created by the mechanical transfer

of the infill panel self-weight from the horizontal profiles to the vertical ones (see Figure 7).

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