EN 15026:2023

Hygrothermal performance of building components and building elements - Assessment of moisture transfer by numerical simulation

This document specifies the model components to be used in a numerical hygrothermal simulation model for calculating the transient transfer of heat and moisture through building structures.
This document specifies a method to be used for validating a numeric hygrothermal simulation model claiming conformity with this document.

Wärme- und feuchtetechnisches Verhalten von Bauteilen und Bauelementen - Bewertung der Feuchteübertragung durch numerische Simulation

Dieses Dokument legt die in einem numerischen Modell der wärme- und feuchtetechnischen Simulation zur Berechnung der transienten Wärme- und Feuchteübertragung innerhalb von Bauwerken zu verwendenden Modellkomponenten fest.
Dieses Dokument legt ein Verfahren fest, das dazu dient, zu validieren, dass das betreffende numerische Modell der wärme- und feuchtetechnischen Simulation diesem Dokument entspricht.

Performance hygrothermique des composants et parois de bâtiments - Évaluation du transfert d’humidité par simulation numérique

Le présent document spécifie les composantes de modèle à utiliser dans le cadre d’un modèle de simulation hygrothermique numérique pour calculer le transfert transitoire de chaleur et d’humidité à travers les structures des bâtiments.
Le présent document spécifie une méthode à utiliser pour valider la conformité au présent document d’un modèle de simulation hygrothermique numérique.

Higrotermalno obnašanje sestavnih delov stavb in elementov stavb - Ocenjevanje prenosa vlage z numerično simulacijo

Ta dokument določa komponente modela, ki se uporabljajo v numeričnem higrotermalnem simulacijskem modelu za izračun prenosa toplote in vlage skozi stavbne konstrukcije.
Ta dokument določa metodo, ki se uporablja za potrjevanje numeričnega higrotermalnega simulacijskega modela kot dokaz skladnosti s tem dokumentom.

General Information

• Status: Published
• Publication Date: 25-Jul-2023
• ICS: 91.120.01 - Protection of and in buildings in general
• Technical Committee: CEN/TC 89 - Thermal performance of buildings and building components
• Drafting Committee: CEN/TC 89/WG 10 - Moisture
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 26-Jul-2023
• Due Date: 01-Jun-2023
• Completion Date: 26-Jul-2023
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Ref Project: SIST EN 15026:2023 - Hygrothermal performance of building components and building elements - Assessment of moisture transfer by numerical simulation

Relations

• Replaces: EN 15026:2007 - Hygrothermal performance of building components and building elements - Assessment of moisture transfer by numerical simulation
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2023
Nadomešča:
SIST EN 15026:2007
Higrotermalno obnašanje sestavnih delov stavb in elementov stavb - Ocenjevanje
prenosa vlage z numerično simulacijo
Hygrothermal performance of building components and building elements - Assessment
of moisture transfer by numerical simulation
Wärme- und feuchtetechnisches Verhalten von Bauteilen und Bauelementen -
Bewertung der Feuchteübertragung durch numerische Simulation
Performance hygrothermique des composants et parois de bâtiments - Évaluation du
transfert d’humidité par simulation numérique
Ta slovenski standard je istoveten z: EN 15026:2023
ICS:
91.120.30 Zaščita pred vlago Waterproofing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 15026
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2023
EUROPÄISCHE NORM
ICS 91.120.01 Supersedes EN 15026:2007
English Version
Hygrothermal performance of building components and
building elements - Assessment of moisture transfer by
numerical simulation
Performance hygrothermique des composants et Wärme- und feuchtetechnisches Verhalten von
parois de bâtiments - Évaluation du transfert Bauteilen und Bauelementen - Bewertung der
d'humidité par simulation numérique Feuchteübertragung durch numerische Simulation
This European Standard was approved by CEN on 26 June 2023.

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, 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, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 15026:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 5
Introduction . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, symbols and units . 8
4 Hygrothermal formulae and material properties . 10
4.1 Assumptions . 10
4.2 Balance formulae . 11
4.2.1 General. 11
4.2.2 Internal energy density . 11
4.2.3 Additional source terms . 12
4.3 Relations between driving potentials and conserved quantities . 12
4.4 Transport of heat and moisture . 12
4.4.1 General. 12
4.4.2 Heat and enthalpy transport inside materials . 12
4.4.3 Moisture transport . 13
4.4.4 Moisture transport across material interfaces/vapour retarders/foils . 14
4.4.5 Internal air layers . 15
4.5 Material properties . 15
5 Boundary and initial conditions . 15
5.1 Inside conditions . 15
5.1.1 Usage conditions . 15
5.1.2 Parameters . 16
5.1.3 Sources of data . 16
5.2 Outside conditions . 16
5.2.1 Sources of data . 16
5.2.2 Climate parameters . 17
5.3 Interpolation of tabulated climatic data . 17
5.4 Boundary heat and moisture flows . 18
5.4.1 Heat transfer . 18
5.4.2 Vapour diffusion . 21
5.4.3 Convective latent heat flow . 21
5.4.4 Wind driven rain . 21
5.5 Initial conditions . 22
6 Numerical simulation . 22
6.1 Background . 22
6.2 Geometrical modelling . 23
6.3 Grid and time step sensitivity studies . 23
7 Documentation of input data and results . 24
7.1 General. 24
7.2 Problem description . 24
7.2.1 General. 24
7.2.2 Scope and subject of simulation . 24
7.3 Model geometry and input parameters . 24
7.3.1 Simulated geometry . 24
7.3.2 Initial conditions . 24
7.3.3 Boundary conditions . 24
7.3.4 Material parameters . 25
7.3.5 Auxiliary models . 25
7.3.6 Output specifications . 25
7.4 Simulation method and numerical properties . 25
7.4.1 General . 25
7.4.2 Simulation tool . 25
7.4.3 Numerical simulation properties . 25
7.4.4 Numerical accuracy control . 26
7.5 Calculation report . 26
7.5.1 General . 26
7.5.2 Display of results . 26
7.5.3 Interpretation of the results . 26
Annex A (informative) Material parameters . 28
A.1 General . 28
A.2 Heat storage . 28
A.3 Heat transport . 28
A.4 Moisture storage . 30
A.5 Moisture transport properties . 31
A.5.1 General . 31
A.5.2 Water vapour diffusion resistance . 31
A.5.3 Liquid transport properties . 33
A.6 Material-related model limitations. 34
A.6.1 General . 34
A.6.2 Influence of material boundaries on liquid moisture transport . 34
A.6.3 Hysteresis phenomena . 34
A.6.4 Swelling . 35
A.6.5 Weathering and ageing .
...