EN ISO 12631:2012

Thermal performance of curtain walling - Calculation of thermal transmittance (ISO 12631:2012)

This standard specifies a procedure for calculating the thermal transmittance of curtain wall structures.

Wärmetechnisches Verhalten von Vorhangfassaden - Berechnung des Wärmedurchgangskoeffizienten (ISO 12631:2012)

Diese Internationale Norm legt ein Verfahren zur Ermittlung des Wärmedurchgangskoeffizienten von
Vorhangfassaden fest, die aus verglasten und/oder opaken Paneelen, die in Rahmen eingebaut werden oder
mit Rahmen verbunden sind, bestehen.
Die Berechnung umfasst
 unterschiedliche Verglasungsarten, z. B. aus Glas oder Kunststoff, einfache und mehrfache
Verglasungen, Verglasungen mit oder ohne Beschichtungen mit niedrigem Emissionsgrad sowie
Verglasungen mit einem Zwischenraum, der mit Luft oder anderen Gasen gefüllt ist;
 Rahmen (aus einem beliebigen Material), mit oder ohne wärmetechnische Trennung;
 verschiedene Arten von opaken Paneelen, die mit Metall, Glas, Keramik oder einem anderen Material
verkleidet sind.
Die Berechnung berücksichtigt den Einfluss von Wärmebrücken am Falz oder an der Fuge zwischen der
verglasten Fläche, dem Rahmen und dem Paneel.
Folgende Faktoren werden in der Berechnung nicht berücksichtigt:
 Einflüsse aus der Sonneneinstrahlung;
 Wärmeübertragung durch Luftdurchlässigkeit;
 Tauverhalten;
 Einfluss von Abschlüssen;
 zusätzliche Wärmeübertragung an den Ecken und Kanten der Vorhangfassade;
 Verbindungen mit das Tragwerk und die dazu verwendeten Verbindungsmittel;
 Vorhangfassaden mit eingebauter Heizung.

Performance thermique des façades-rideaux - Calcul du coefficient de transmission thermique (ISO 12631:2012)

Toplotne značilnosti obešenih fasad - Izračun toplotne prehodnosti (ISO 12631:2012)

Ta mednarodni standard določa metodo za izračun toplotne prehodnosti obešenih fasad iz steklenih in/ali prosojnih plošč, nameščenih v okvirje ali povezanih z okvirji. Izračun vključuje: – različne vrste zasteklitve, npr. iz stekla ali plastike; enojna ali večkratna zasteklitev; z nanosom ali brez nanosa nizke emisivnosti; z vmesnimi prostori, napolnjenimi z zrakom ali drugimi plini; – okvirje (iz katerega koli materiala) s toplotnimi prekinitvami ali brez; – različne vrste prosojnih plošč, prevlečenih s kovino, steklom, keramiko ali drugimi materiali. Toplotni mostovi na znižanju ali stiku med zastekljenim območjem, območjem okvirja in območjem plošče so vključeni v izračun. Izračun ne vključuje: – učinkov sončnega sevanja; – prenosa toplote zaradi puščanja zraka; – izračuna kondenzacije; – učinkov polken; – dodatnega prenosa toplote v kotih in na robovih zidov za zavese; – povezav z glavno stavbno strukturo ali skozi pritrdilne spoje; – sistemov zidov za zavese z vgrajenim gretjem.

General Information

• Status: Withdrawn
• Publication Date: 30-Sep-2012
• Withdrawal Date: 18-Jul-2017
• ICS: 91.060.10 - Walls. Partitions. Facades
• ICS: 91.120.10 - Thermal insulation of buildings
• Technical Committee: CEN/TC 89 - Thermal performance of buildings and building components
• Drafting Committee: CEN/TC 89/WG 7 - Thermal properties of doors and windows
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Completion Date: 19-Jul-2017
• Ref Project: SIST EN ISO 12631:2013 - Thermal performance of curtain walling - Calculation of thermal transmittance (ISO 12631:2012)

Relations

• Replaces: EN 13947:2006 - Thermal performance of curtain walling - Calculation of thermal transmittance
• Effective Date: 03-Oct-2009
• Replaced By: EN ISO 12631:2017 - Thermal performance of curtain walling - Calculation of thermal transmittance (ISO 12631:2017)
• Effective Date: 04-Jun-2014

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2013
1DGRPHãþD
SIST EN 13947:2007
7RSORWQH]QDþLOQRVWLREHãHQLKIDVDG,]UDþXQWRSORWQHSUHKRGQRVWL,62

Thermal performance of curtain walling - Calculation of thermal transmittance (ISO
12631:2012)
Wärmetechnisches Verhalten von Vorhangfassaden - Berechnung des
Wärmedurchgangskoeffizienten (ISO 12631:2012)
Performance thermique des façades-rideaux - Calcul du coefficient de transmission
thermique (ISO 12631:2012)
Ta slovenski standard je istoveten z: EN ISO 12631:2012
ICS:
91.060.10 Stene. Predelne stene. Walls. Partitions. Facades
Fasade
91.120.10 Toplotna izolacija stavb Thermal insulation
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 12631
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2012
ICS 91.120.10 Supersedes EN 13947:2006
English Version
Thermal performance of curtain walling - Calculation of thermal
transmittance (ISO 12631:2012)
Performance thermique des façades-rideaux - Calcul du Wärmetechnisches Verhalten von Vorhangfassaden -
coefficient de transmission thermique (ISO 12631:2012) Berechnung des Wärmedurchgangskoeffizienten (ISO
12631:2012)
This European Standard was approved by CEN on 30 September 2012.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12631:2012: E
worldwide for CEN national Members.

Contents Page
Foreword .3
Foreword
This document (EN ISO 12631:2012) has been prepared by Technical Committee CEN/TC 89 “Thermal
performance of buildings and building components”, the secretariat of which is held by SIS, in collaboration
with Technical Committee ISO/TC 163 "Thermal performance and energy use in the built environment".
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 April 2013, and conflicting national standards shall be withdrawn at the
latest by April 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 13947:2006.
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, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

INTERNATIONAL ISO
STANDARD 12631
First edition
2012-10-01
Thermal performance of curtain
walling — Calculation of thermal
transmittance
Performance thermique des façades-rideaux — Calcul du coefficient de
transmission thermique
Reference number
ISO 12631:2012(E)
©
ISO 2012
ISO 12631:2012(E)
©  ISO 2012
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
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Published in Switzerland
ii © ISO 2012 – All rights reserved

ISO 12631:2012(E)
Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Normative references . 1
3  Terms, definitions, symbols and units . 2
3.1  Terms and definitions . 2
3.2  Symbols and units . 3
3.3  Subscripts . 3
3.4  Superscripts . 4
4  Geometrical characteristics . 4
4.1  Main principles . 4
4.2  Internal depth . 6
4.3  Boundaries of curtain wall structures . 6
5  Cut-off planes and partitioning of thermal zones . 9
5.1  Rules for thermal modelling . 9
5.2  Cut-off planes of the geometrical model . 9
6  Calculation of curtain wall transmittance . 9
6.1  Methodologies . 9
6.2  Single assessment method . 10
6.3  Component assessment method . 16
6.4  Thermal transmittance of a curtain wall built of different elements . 21
7  Input data . 21
8  Report . 22
8.1  Section drawings . 22
8.2  Overview drawing of the whole curtain wall element . 23
8.3  Values used for calculation . 23
8.4  Presentation of results . 23
Annex A (informative) Guidance for calculating the thermal transmittance U of curtain walling
cw
using the two methods . 24
Annex B (informative) Linear thermal transmittance of junctions . 25
Annex C (normative) A method for calculating the thermal effect of screws using a 2D numerical
method and the procedures specified in ISO 10077-2:2012 . 33
Annex D (normative) Ventilated and unventilated air spaces . 36
Annex E (informative) Component method: Calculation example . 39
Annex F (informative) Single assessment method: Calculation example . 45
Annex G (normative) Parallel routes in normative references . 48
Bibliography . 49

ISO 12631:2012(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 12631 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 89, Thermal performance of buildings and building components, the secretariat of which is held by
SIS, in collaboration with ISO Technical Committee TC 163, Thermal performance and energy use in the built
environment, Subcommittee SC 2, Calculation methods, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
iv © ISO 2012 – All rights reserved

ISO 12631:2012(E)
Introduction
The design and construction of curtain wall systems is complex. This International Standard specifies a
procedure for calculating the thermal transmittance of curtain wall structures.
Curtain walls often contain different kinds of materials, joined in different ways, and can exhibit numerous
variations of geometrical shape. With such a complex structure, the likelihood of producing thermal bridges
across the curtain wall envelope is quite high.
The results of calculations, carried out following the procedures specified in this International Standard, can be
used for comparison of the thermal transmittance of different types of curtain wall or as part of the input data
for calculating the heat used in a building. This International Standard is not suitable for determining whether
or not condensation will occur on the structure surfaces nor within the structure itself.
Two methods are given in this International Standard:
 single assessment method (see 6.2);
 component assessment method (see 6.3).
Guidance on the use of these two methods is given in Annex A. Calculation examples for these two methods
are given in Annex E and Annex F.
Testing according to ISO 12567-1:2010 is an alternative to this calculation method.
The thermal effects of connections to the main building structure as well as fixing lugs can be calculated
according to ISO 10211:2007.
The thermal transmittance of the frame, U , is defined according to ISO 10077-2:2012 or EN 12412-2:2003
f
together with Annex A. The thermal transmittance of glazing units, U , is defined according to the documents
g
listed in Table G.1 which does not include the edge effects. The thermal
...