ISO/TR 52003-2:2017

TECHNICAL ISO/TR
REPORT 52003-2
First edition
2017-06
Energy performance of buildings —
Indicators, requirements, ratings and
certificates —
Part 2:
Explanation and justification of ISO
52003-1
Performance énergétique des bâtiments — Indicateurs, exigences,
classification et certificats —
Partie 2: Explication et justification de l’ISO 52003-1
Reference number
ISO/TR 52003-2:2017(E)
©
ISO 2017

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ISO/TR 52003-2:2017(E)

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ISO/TR 52003-2:2017(E)

Contents Page
Foreword .v
Introduction .vi
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Symbols and abbreviations . 1
4.1 Symbols . 1
4.2 Subscripts . 2
5  Description of the document . 2
5.1 General . 2
5.2 Selection criteria between possible options. 4
5.3 Input and output data . 4
6  Relation between EPB features, indicators, requirements, ratings and certificates .4
7  Energy performance features and their indicators . 9
7.1 General . 9
7.2 Normalization to building size . 9
7.3 Energy performances and their indicators . 9
7.3.1 Overall energy performances. 9
7.3.2 Partial energy performances . 9
7.4 Ratios of identical/similar quantities as indicators for energy performances . 9
8  Tailoring for requirements and for ratings .10
8.1 Two approaches .10
8.2 Project characteristics for tailoring .12
9 Energy performance requirements .13
9.1 General .13
9.2 Choice of the mix of requirements .14
9.2.1 General.14
9.2.2 New buildings .14
9.2.3 Existing buildings (renovations and extensions) .15
9.3 Constant or variable value requirements .15
9.3.1 Tailoring requirements to individual project characteristics .15
9.3.2 Tightening the requirements over time .17
9.4 Actual strictness . .17
9.5 Reporting template for the overall energy performance .18
10  EPB rating .18
10.1 General .18
10.2 EPB rating procedures .18
10.2.1 Reference point - National legal requirements for new buildings .19
10.2.2 Expressions of reference point of the scale .19
10.2.3 Proposal for the shape of the scale .20
10.2.4 Conclusions on Method 2 .21
10.3 Reference values .21
11  Energy performance certificate .21
11.1 General .21
11.2 Content of the procedure for a building energy certificate .21
11.3 Content of the energy performance certificate .21
11.3.1 General.21
11.3.2 Default graphical representation model .22
11.4 Recommendations .22
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ISO/TR 52003-2:2017(E)

12 Quality control .22
13  Compliance check .23
Annex A (informative) Input and method selection data sheet — Template.24
Annex B (informative) Input and method selection data sheet — Default choices .25
Annex C (informative) Illustration of the variable value of the overall primary energy use
per floor area for a given set of technical measures .27
Annex D (informative) Procedure for building energy performance classification .30
Annex E (informative) Energy label model .31
Bibliography .34
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ISO/TR 52003-2:2017(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL:
w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 163, Thermal performance and energy use
in the built environment, in collaboration with ISO/TC 205, Building environment design, and with the
European Committee for Standardization (CEN) Technical Committee CEN/TC 89, Thermal performance
of buildings and building components, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 52003 series can be found on the ISO website.
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ISO/TR 52003-2:2017(E)

Introduction
Relation between this document and the accompanying International Standard
For proper understanding of the present document, it is necessary to read it in close conjunction,
clause by clause, with ISO 52003-1. First, the corresponding clause in Part 1 needs to be read; then
the complementary information in the same clause in this report can be read. Essential information
provided in Part 1 is not repeated in this part. References to a clause refer to the combined content of
[14] [15]
that clause in both parts 1 and 2. Brief articles on the subject can be found in and .
The set of EPB standards, technical reports and supporting tools
In order to facilitate the necessary overall consistency and coherence, in terminology, approach,
input/output relations and formats, for the whole set of EPB-standards, the following documents and
tools are available:
a) a document with basic principles to be followed in drafting EPB-standards: CEN/TS 16628:2014,
[6]
Energy Performance of Buildings - Basic Principles for the set of EPB standards ;
b) a document with detailed technical rules to be followed in drafting EPB-standards:
CEN/TS 16629:2014, Energy Performance of Buildings - Detailed Technical Rules for the set of EPB-
[7]
standards ;
The detailed technical rules are the basis for the following tools:
1) a common template for each EPB standard, including specific drafting instructions for the relevant
clauses;
2) a common template for each technical report that accompanies an EPB standard or a cluster of EPB
standards, including specific drafting instructions for the relevant clauses;
3) a common template for the spreadsheet that accompanies each EPB (calculation) standard, to
demonstrate the correctness of the EPB calculation procedures.
Each EPB standard follows the basic principles and the detailed technical rules and relates to the
[10]
overarching EPB standard, ISO 52000-1 .
One of the main purposes of the revision of the EPB standards has been to enable that laws and
regulations directly refer to the EPB standards and make compliance with them compulsory. This
requires that the set of EPB standards consists of a systematic, clear, comprehensive and unambiguous
set of energy performance procedures. The number of options provided is kept as low as possible,
taking into account national and regional differences in climate, culture and building tradition, policy
and legal frameworks (subsidiarity principle). For each option, an informative default option is provided
(Annex B).
Rationale behind the EPB Technical Reports
There is a risk that the purpose and limitations of the EPB standards will be misunderstood, unless
the background and context to their contents – and the thinking behind them – is explained in some
detail to readers of the standards. Consequently, various types of informative contents are recorded
and made available for users to properly understand, apply and nationally or regionally implement the
EPB standards.
If this explanation would have been attempted in the standards themselves, the result is likely to be
confusing and cumbersome, especially if the standards are implemented or referenced in national or
regional building codes.
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Therefore each EPB standard is accompanied by an informative technical report, like this one, where
all informative content is collected, to ensure a clear separation between normative and informative
[7]
contents (see CEN/TS 16629 ):
— to avoid flooding and confusing the actual normative part with informative content;
— to reduce the page count of the actual standard; and
— to facilitate understanding of the set of EPB standards.
[12]
This was also one of the main recommendations from the European CENSE project that laid the
foundation for the preparation of the set of EPB standards.
This document
This document accompanies ISO 52003-1, which forms part of the set of EPB standards.
The role and the positioning of the accompanying standard in the set of EPB standards is defined in the
Introduction to ISO 52003-1.
Accompanying spreadsheet(s)
Because in the accompanying document ISO 52003-1 no calculation procedures are defined, an
accompanying calculation spreadsheet is not relevant.
History of this document and the accompanying International Standard
[2]
The first standard on this topic was EN 15217:2007 . It was developed as part of Mandate 343 of the
[3] [4]
EC to CEN to support the EPBD (2003) . An upgrade of it was published as ISO 16343:2013 . The
document has been thoroughly reworked and split in a normative International Standard (Part 1) and
[5]
the present informative document (Part 2) as part of Mandate 480 of the EC to CEN .
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TECHNICAL REPORT  ISO/TR 52003-2:2017(E)
Energy performance of buildings — Indicators,
requirements, ratings and certificates —
Part 2:
Explanation and justification of ISO 52003-1
1  Scope
This document refers to ISO 52003-1. It contains information to support the correct understanding and
use of ISO 52003-1 and does not contain any normative provisions.
NOTE The relation with other EPB standards, product standards and product policy is shown schematically
in Figure 4 of Clause 6.
2  Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
More information on the use of EPB module numbers for normative references between EPB standards
[11]
is given in ISO/TR 52000-2 .
ISO 52003-1:2017, Energy performance of buildings – Indicators, requirements, ratings and certificates –
Part 1: General aspects and application to the overall energy performance
3  Terms and definitions
For the purposes of this document, the terms and definitions given in the accompanying EPB document,
ISO 52003-1, apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
[11]
More information on some key EPB terms and definitions is given in ISO/TR 52000-2 .
4  Symbols and abbreviations
4.1  Symbols
For the purposes of this document, the symbols given in ISO 52003-1 and the following apply.
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[11]
More information on key EPB symbols is given in ISO/TR 52000-2 .
Symbol Name of quantity Unit
A area m²
c constant a)
f factor -
f shape factor -
V volume m³
a) varies with the context
4.2  Subscripts
For the purposes of this document, the subscripts given in ISO 52003-1 and the following apply.
More information on key EPB subscripts is given in ISO/TR 52000-2.
c conditioned
env envelope
use useful
5  Description of the document
5.1  General
Figure 1 shows in a first, simplified step and in a schematic manner, the main uses that can be made of
the EPB indicators.
EPB indicators are numeric quantities that are the intermediate or final output of the EPB assessment
standards (see also Figure 4 in Clause 6). They can be the result of either calculations (e.g. a thermal
transmittance value) or of measurements (e.g. the air tightness value of the thermal envelope) or a
combination of both (e.g. an overall energy performance value that is partly based on a measured air
tightness). Ideally, all mathematical operations of a technical variable are defined in the EPB assessment
standards and the value as such (and its definition) are directly ready for further use, without the need
for further mathematical manipulation.
The EPB indicators can be used in several different ways by public and private actors. A first major
use of EPB indicators is to impose regulatory EPB requirements on construction works of all kinds. A
second major use is to rate the energetic quality of the considered EPB feature through comparison
with benchmarks. The EPB requirements can serve as one of the references for the rating. There can
still be other uses, such as the use of a variable as target function for design optimization, e.g. the least
life cycle cost.
Selected EPB indicators, ratings, requirements and their (non)compliance (if applicable), and other
information (such as recommendations for improvement of the energy performance) can be included in
the EPB certificate, and its detailed report.
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Figure 1 — Simplified schematic overview of the relations between various EPB aspects
Figure 2 illustrates in dotted lines potential additional interactions. In order to achieve equitable
requirements or ratings, it can be necessary for many indicators to use in a first instance variable
values as requirement or reference. Such variable values are tailored to the characteristics of each
individual project. For ease of communication, the primary indicator can be converted in a second
instance into a derived indicator by taking its ratio to the variable requirement or reference value. The
derived, secondary indicator then again allows the requirement or rating reference to be a constant
value, which can greatly facilitate communication. Generally speaking, it seems desirable that all
mathematical operations are defined in the actual EPB assessment standards. But for derived indicators
that are intrinsically related to the (requirement and rating) policy choices, the last few mathematical
calculations inevitably can only be defined in a regulatory context.
Figure 2 — Full schematic overview of the relations between various EPB aspects
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5.2  Selection criteria between possible options
No additional information beyond the accompanying document.
5.3 Input and output data
No additional information beyond the accompanying document.
6  Relation between EPB features, indicators, requirements, ratings and
certificates
The conceptual table of Figure 3 is an alternative to the presentation in Figure 2. It allows a user to
visualize and report the practical choices that a given (public or private) actor makes with respect to its
uses of the EPB indicators.
On top of each of the columns of the table, the number of the clause in ISO 52003-1 and ISO/TR 52003-2
that deals with the particular aspect is given.
In the first column, the different EPB features can be listed. (For reasons of sizing, here these are
done in an exemplary, non-exhaustive manner.) They can be grouped in 3 categories: overall energy
performances, partial energy performances and the energy performances of products (“traded
commodities”).
NOTE 1 The product group can of course include devices that are not used in buildings (e.g. vehicles) or that
are not always considered in the building energy performance assessment (for instance, the energy use of plug-
in appliances such as refrigerators, televisions, computers etc., is usually not included in the calculations of the
energy use of the building, but is usually part of the measured overall building energy performance).
In the second column, the possible indicators for each of the EPB features can be listed.
Clause 7 Clause 7 Clause 9 Clause 10 -
EPB feature indicator requirements rating other uses
new existing
OVERALL ENERGY
PERFORMANCES
primary energy use X
non-renewable pri- X
mary energy use
...
PARTIAL ENERGY
PERFORMANCES
... ...
lighting LENI
...
fans
specific fan power
...
systems
efficiency X
expenditure factor
... ...
heating need
...
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Clause 7 Clause 7 Clause 9 Clause 10 -
EPB feature indicator requirements rating other uses
new existing
cooling need
...
envelope airtight-
ness
specific air leakage
...
overall thermal mean thermal
insulation transmittance
component ther-
mal insulation
thermal X
transmittance
temperature factor
...
PRODUCT
ENERGY
PERFORMANCES
...
boilers
pumps
fans
...
refrigerators X
televisions
...
vehicles
...
Figure 3 — Tabular overview of the relation between various EPB aspects
The third column concerns requirements. It is subdivided into 2 sub-columns, dealing with new
construction on the one hand and works in existing buildings on the other hand. With a cross, the EPB
indicators for which requirements are set can be indicated. These can differ between new construction
(focus typically on one or more overall EPB indicators) and works in existing buildings (by their nature,
focus typically on the elements and systems that are the object of the works).
In the fourth column crosses can indicate the indicators that are rated.
The empty fifth column reminds that there can be many more uses for the EPB indicators. The column
can be replaced by several columns if the purpose is to illustrate/document practical instances where
such other uses apply.
In Figure 4, the further relation with the assessment methods is shown. The arrows in the figure
represent the transfer of data (output of 1 module is input for 1 or more other modules) towards the
final use of a result (e.g. as indicator).
Product standards assess basic characteristics either by measurement or calculation, or a combination
of both. Sometimes there is for a given product an alternative, free choice between measurement and
calculation methods (e.g. the thermal transmittance of glazing). This choice is represented by the ellipse
in Figure 4. Product calculation methods usually rely on measured features of its composing elements
(e.g. coating with low thermal emissivity in glazing, or dimensions of a frame) or on production control
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schemes (e.g. noble gas filling in glazing). The product characteristics thus assessed can be used either
directly as indicator (e.g. full and part load efficiencies of a boiler) or combined in a further calculation
model to give a more comprehensive assessment (e.g. typical seasonal efficiency, taking into account
auxiliary energy use).
On-site measurements and inspections can evaluate a building as a whole or its various elements and
subsystems as they are effectively built/installed, sometimes also including the way they are used
(controller settings, user behaviour, etc.). Examples are:
— measurement of the air tightness of the envelope or of the ducts;
— measurement of ventilation flow rates;
— measurement of boiler efficiency; and
— measurement of the overall energy uses, etc.
These measurement results can be used directly as indicator (or after minor further processing, e.g.
conversion of delivered to primary energy) and/or they can serve as input for EPB calculations.
The EPB calculation standards are an extensive set of calculation models with multiple interactions
among them. The ultimate output are overall energy performance indicators, but a very large number
of intermediate results can potentially be used as partial energy performance indicat
...