IEC 62999:2016

IEC 62999 ®
Edition 1.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electric room heating – Underfloor heating – Performance characteristics –
Definitions, method of testing, sizing and formula symbols

Chauffage électrique de locaux – Chauffage par le sol – Caractéristiques de
performance – Définitions, méthode d'essai, calibrage et symboles de formule

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IEC 62999 ®
Edition 1.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electric room heating – Underfloor heating – Performance characteristics –

Definitions, method of testing, sizing and formula symbols

Chauffage électrique de locaux – Chauffage par le sol – Caractéristiques de

performance – Définitions, méthode d'essai, calibrage et symboles de formule

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 97.100.10 ISBN 978-2-8322-3213-2

– 2 – IEC 62999:2016 © IEC 2016
CONTENTS
FOREWORD .6
1 Scope .8
2 Normative references .8
3 Terms and definitions .8
4 Method of testing for the determination of characteristics of performance . 16
4.1 General . 16
4.2 Standard heating load per unit area . 16
4.3 Maximum power rating per unit area . 16
4.4 Maximum surface temperature . 17
4.5 Maximum floor surface temperature for underfloor storage heating . 18
4.6 Room air temperature . 19
4.7 Internal surface temperatures on the surrounding surfaces of the room . 20
4.8 Thermal pre-conditioning of the room to be tested . 20
4.9 Floor temperature in the case of continuous local hot spots . 21
4.10 Floor temperature of underfloor storage heating through failure of a
switching, controlling or regulation apparatus . 23
4.11 Floor temperature of controlled underfloor heating and underfloor direct
heating through failure of a switching, controlling or regulation apparatus . 23
4.12 Regulation of room temperature using peripheral areas for underfloor
storage heating . 23
4.13 Regulation of room temperature using controlled underfloor heating and

underfloor direct heating . 23
4.14 Regulation of room temperature using underfloor warming . 24
4.15 Relationship of coefficients of heat transfer . 24
4.16 Insulating layers . 24
4.17 Edging insulation strips . 25
4.18 Damp-proofing . 25
4.19 Electrical auxiliary heating . 26
4.20 Load distribution layer in electrical underfloor heating . 26
4.21 Bedding in or under heating screed or directly below floor covering . 26
4.22 Dry laying of electrical heating elements. 26
4.23 Heating element . 26
4.24 Heating cable and laminar heating element . 26
4.24.1 Heating cable for bedding in or under screeding or directly below floor
covering. 26
4.24.2 Heating cable for dry laying . 26
4.24.3 Laminar heating elements for installation below or in screeding . 27
4.25 Characteristics of heating cables . 27
4.26 Characteristics of laminar heating elements . 27
4.27 Cold tails . 27
4.28 Point of connection . 27
4.29 Bending radius of the heating cable . 27
4.30 Heating element labelling . 27
4.31 Pulsation factor . 27
4.32 Installation of heating elements for underfloor direct heating . 28
4.33 Adhesive and fixing material . 28
4.34 Permanent installation areas . 28

4.35 Pre-heating of screeding . 28
4.36 Floor coverings . 28
4.37 Control and regulation equipment . 28
4.38 Control and regulation equipment for underfloor storage heating . 28
4.39 Control and regulation equipment for controlled underfloor heating and

underfloor direct heating . 28
4.40 Floor temperature measurement . 29
4.41 Auxiliary supply period . 29
4.42 Period of room use . 29
4.43 Insulation and dielectric resistance of the heating element . 29
4.44 Instructions for construction workers . 29
4.44.1 Protective measures when pouring flooring screed . 29
4.44.2 Pouring the screed . 29
4.45 Data for owner and user of the building . 29
4.46 Report of testing . 30
Annex A (informative) Sizing procedure – Range of application and purpose . 31
A.1 General . 31
A.2 Basic principles – Basic parameters of the room to be heated . 31
A.2.1 General . 31
A.2.2 Standard heat load of an underfloor heated room . 31
A.2.3 Standard heating load per unit area . 31
A.2.4 Effective heat storage capacity of the room to be heated . 32
A.2.5 Peripheral conditions and limiting values . 32
A.3 Sizing an underfloor heating system . 33
A.3.1 Storage layer depth of an underfloor heating system .
...