SIST EN ISO 10211-1:1997

SLOVENSKI STANDARD
01-december-1997
7RSORWQLPRVWRYLY]JUDGEDK7RSORWQLWRNRYLLQSRYUãLQVNHWHPSHUDWXUHGHO
6SORãQLUDþXQVNLSRVWRSNL
Thermal bridges in building construction - Heat flows and surface temperatures - Part 1:
General calculation methods (ISO 10211-1:1995)
Wärmebrücken im Hochbau - Wärmeströme und Oberflächentemperaturen - Teil 1:
Allgemeine Berechnungsverfahren (ISO 10211-1:1995)
Ponts thermiques dans le bâtiment - Calcul des températures superficielles et des flux
thermiques - Partie 1: Méthodes de calcul générales (ISO 10211-1:1995)
Ta slovenski standard je istoveten z: EN ISO 10211-1:1995
ICS:
91.120.10 Toplotna izolacija stavb Thermal insulation
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

ISO
INTERNATIONAL
10211-1
STANDARD
First edition
1995-08-15
Thermal bridges in building construction -
Heat flows and surface temperatures -
Part 1:
General calculation methods
Flux de chaleur et temperatures
Ponts thermiques dans Ie batiment -
superficielles -
Partie 7: Methodes g&Grales de calcul
Reference number
ISO 1021 l-l :1995(E)
--
ISO 10211-1:1995(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. Esch 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.
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.
International Standard ISO 1021 l-l was prepared by the European
Committee for Standardization (CEN) in collaboration with Technical
Committee lSO/TC 163, Thermal insulation, Subcommittee SC 2,
Cakulation methods, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
ISO 10211 consists of the following Part, under the general title Thermal
Heat flows and surface temperatures:
bridges in building construction -
Part 7: General calculation methods
The following part is in preparation:
- Part 2: Calculation of linear thermal bridges
Annexes A, B and C form an integral part of this part of ISO 10211.
Annexes D, E, F and G are for information only.
0 ISO 1995
All rights reserved. Unless otherwise specified, no patt of this publication may be reproduced
or- utilized in any form or by any means, electrontc or mechanical, including protocopying and
mrcrofilm, without Permission in writing from the publisher.
International Orga nization for Standardization
CH-l 21 1 Geneve 20 l Switzerla nd
Case postale 56 l
Printed in Switzerland
ISO 10211=1:1995(E)
CONTENTS
iv
Foreword
iv
Introduction
1 Scope 1
2 Normat ive references
3 Definiti ons and Symbols 2
4 Principl
5 Modelling of the construction
5.1 Rules for modelling
5.2 Conditions for simplifying the geometrical model
6 Calculation values 19
6.1 Given calculation values
6.2 Methods of determining the calculation values
7 Calculation method
7.1 Calculation rules 22
7.2 Determination of the thermal coupling coefficients
and the heat flowrate 22
7.3 Determination of the temperature at the internal surface
8 Input and output data 26
8.1 Input data
8.2 Output data
Validation of calculation methods 28
Annex A(normative)
Annex B(normative) Equivalent thermal conductivity of air cavities 32
Determination of the linear and Point thermal
Annex C(normative)
transmittances
Annex D(informative) Examples of the use of quasi-homogeneous layers
Annex E(informative) lnternal surface resistances 44
Annex F(informative) Determination of L- and g-values for more than two
boundary temperatures 51
Annex G(informative) Assessment of surface condensation 54
0.0
Ill
ISO 10211=1:1995(E)
Fore word
The text of EN ISO 1021 1-l : 1995 has been prepared by Technical Committee CEN/TC 89
“Thermal Performance of buildings and building components” in collaboration with ISO/TC 163
“Thermal insulation” .
This European Standard shall be given the Status of a National Standard, either by publicatiori
of an identical text or by endorsement, at the latest by February 1996, and conflicting national
Standards shall be withdrawn at the latest by February 1996.
According to CEN/CENELEC Internal Regulations, the following countries are bound to implement
this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, lceland,
Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the
United Kingdom.
Introduction
Thermal bridges, which in general occur at any junction between building components or
where the building structure changes composition, have two consequences:
a) a Change in heat flow rate
and
b) a Change in internal surface temperature
compared with those of the unbridged structure.
Although similar calculation procedures are used, the procedures are not identical for the
calculation of heat flows and of surface temperatures.
Usuallv a thermal bridge gives rise to 3-dimensional or 2-dimensional heat flows, which
tan beprecisely determined using detailed numerical calculation methods as described in
this Standard. These are termed “Class A” methods. and Part 1 of this Standard lays down
criteria which have to be satisfied in Order that a method tan be described as being “Class
A ” .
In manv applications numerical calculations which are based on a 2-dimensional
representation of the heat flows provide results with an adequate accuracy. These are
termed “Class B” methods.
Part 2 of this Standard lavs down criteria for the calculation of linear thermal bridges
M
which have to be satisfied in Order that the calculation method tan be described as beirigg
“Class B”.
Other less precise but much simpler methods. which are not based on numerical calculation
may provide adequate assessment of the additional heat loss caused by thermal bridges.
Simplified methods are given in prEN ISO 14683. Thermal bridges in building
constructions - Linear thermal transmittance - Simplified methods and design values
(ISO/DIS 14683: 1995).
iv
0 ISO
ISO 10211=1:1995(E)
1 Scope
Part 1 of this Standard sets out the specifications on a 3-D and 2-D geometrical model of a
thermal bridge for the numerical calculation of:
- heat flows in Order to assess the Overall heat loss from a building;
minimum surface temperatures in Order to assess the risk of surface condensation.
These specifications include the geometrical boundaries and subdivisions of the model, the
thermal boundary conditions and the thermal values and relationships to be used.
The Standard is based upon the following assumptions:
- steady-state conditions apply;
- all physical properties are independent of temperature;
- there are no heat sources within the building element.
It may also be used for the derivation of linear and Point thermal transmittances and of
surface temperature factors.
2 Normative references
This Standard incorporates by dated and undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and
the publications are listed hereafter. For dated references, subsequent amendments to or
revisions of any of these publications apply to this Standard only when incorporated in it
by amendment or revision. For undated references the latest edition of the publication
referred to applies.
ISO 7345 Thermal insulation - Physical quantities and definitions
prEN 673 Thermal insulation of glazing - Calculation rules for determining the
steady state thermal transmittance of glazing
prEN ISO 6946-1 Building components and building elements - Thermal resistance and
thermal transmittance - Calculation method
prEN ISO 10456 Thermal insulation -
Building materials and products - Determination of
declared and design values
prEN ISO 13789 Thermal Performance of buildings
- Specific transmission heat loss -
Calculation method
ISO 10211=1:1995(E)
3 Definitions and Symbols
3.1 Def initions
For the purposes of this Standard, the definitions of ISO 7345 and the following
definitions apply:
3.1.1 thermal bridge: Part of the building envelope where the otherwise uniform
thermal resistance is significantly changed by:
a) full or partial Penetration of the building envelope by materials with a
different thermal conductivity
and/or
b) a Change in thickness of the fabric
and/or
c) a differente between internal and external areas, such as occur at
wall/floor/ceiling junctions.
3.1.2 3-D geometrical modei: Geometrical model, deduced from building Plans,
such that for each of the orthogonal axes, the Cross section perpendicular to that
axis changes within the boundary of the model (see figure 1).
3.1.3 3-D
...