Thermal performance of curtain walling. Calculation of thermal transmittance

Available format(s)

Hardcopy , PDF

Language(s)

English

Published date

28-11-2017

Publisher

British Standards Institution

This document specifies a method for calculating the thermal transmittance of curtain walls consisting of glazed and/or opaque panels fitted in, or connected to, frames.

The calculation includes:

different types of glazing, e.g. glass or plastic; single or multiple glazing; with or without low emissivity coating; with cavities filled with air or other gases;
frames (of any material) with or without thermal breaks;
different types of opaque panels clad with metal, glass, ceramics or any other material.

Thermal bridge effects at the rebate or connection between the glazed area, the frame area and the panel area are included in the calculation.

The calculation does not include:

effects of solar radiation;
heat transfer caused by air leakage;
calculation of condensation;
effect of shutters;
additional heat transfer at the corners and edges of the curtain walling;
connections to the main building structure nor through fixing lugs;
curtain wall systems with integrated heating.

NOTE Table 1 in the Introduction shows the relative position of this document within the set of EPB standards in the context of the modular structure as set out in ISO 52000-1.

Committee	B/540
DevelopmentNote	Supersedes BS EN 13947 & 10/30234542 DC. (12/2012) Supersedes 16/30310958 DC. (12/2017)
DocumentType	Standard
Pages	64
PublisherName	British Standards Institution
Status	Current
Supersedes	BS EN ISO 12631:2012

Standards	Relationship
EN ISO 12631:2017	Identical
ISO 12631:2017	Identical

CEN/TS 16629:2014	Energy Performance of Buildings - Detailed Technical Rules for the set of EPB-standards
ISO 10211:2017	Thermal bridges in building construction — Heat flows and surface temperatures — Detailed calculations
ISO 10293:1997	Glass in building — Determination of steady-state U values (thermal transmittance) of multiple glazing — Heat flow meter method
EN 673:2011	Glass in building - Determination of thermal transmittance (U value) - Calculation method
CEN/TS 16628:2014	Energy Performance of Buildings - Basic Principles for the set of EPB standards
ISO 9488:1999	Solar energy Vocabulary
ISO 52000-1:2017	Energy performance of buildings — Overarching EPB assessment — Part 1: General framework and procedures
ISO 10077-2:2017	Thermal performance of windows, doors and shutters — Calculation of thermal transmittance — Part 2: Numerical method for frames
ISO 10291:1994	Glass in building — Determination of steady-state U values (thermal transmittance) of multiple glazing — Guarded hot plate method
ISO 12567-1:2010	Thermal performance of windows and doors Determination of thermal transmittance by the hot-box method Part 1: Complete windows and doors
EN 12412-2:2003	Thermal performance of windows, doors and shutters - Determination of thermal transmittance by hot box method - Part 2: Frames
EN 674:2011	Glass in building - Determination of thermal transmittance (U value) - Guarded hot plate method
ISO 10456:2007	Building materials and products — Hygrothermal properties — Tabulated design values and procedures for determining declared and design thermal values
EN 675:2011	Glass in building - Determination of thermal transmittance (U value) - Heat flow meter method
ISO/TR 52000-2:2017	Energy performance of buildings Overarching EPB assessment Part 2: Explanation and justification of ISO 52000-1
ISO 6946:2017	Building components and building elements — Thermal resistance and thermal transmittance — Calculation methods
ISO 10077-1:2017	Thermal performance of windows, doors and shutters — Calculation of thermal transmittance — Part 1: General
ISO/TR 52022-2:2017	Energy performance of buildings Thermal, solar and daylight properties of building components and elements Part 2: Explanation and justification
ISO 7345:1987	Thermal insulation Physical quantities and definitions
ISO 10292:1994	Glass in building — Calculation of steady-state U values (thermal transmittance) of multiple glazing