ISO/FDIS 52120-1

Energy performance of buildings -- Contribution of building automation and controls and building management

Performance énergétique des bâtiments -- Impact de l’automatisation, de la régulation et de la gestion technique des bâtiments

General Information

• Status: Published
• ICS: 91.120.10 - Thermal insulation of buildings
• Technical Committee: ISO/TC 205 - Building environment design
• Drafting Committee: ISO/TC 205/WG 3 - Building Automation and Control System (BACS) Design
• Current Stage: 5000 - FDIS registered for formal approval
• Start Date: 29-Jun-2021

Standards Content (sample)

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 52120-1
ISO/TC 205
Energy performance of buildings —
Secretariat: ANSI
Contribution of building automation
Voting begins on:
2021-09-07 and controls and building
management —
Voting terminates on:
2021-11-02
Part 1:
General framework and procedures
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 52120-1:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. ISO 2021
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ISO/FDIS 52120-1:2021(E)
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© ISO 2021

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ii © ISO 2021 – All rights reserved
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ISO/FDIS 52120-1:2021(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols, subscripts and abbreviated terms ............................................................................................................................ 5

4.1 Symbols ......................................................................................................................................................................................................... 5

4.2 Subscripts .................................................................................................................................................................................................... 5

4.3 Abbreviated terms ............................................................................................................................................................................... 5

5 Description of the method .......................................................................................................................................................................... 6

5.1 Output of the method ........................................................................................................................................................................ 6

5.2 General description of the method(s) ................................................................................................................................. 6

5.3 Selection criteria between the methods ........................................................................................................................... 6

5.4 BAC and TBM functions having an impact on the energy performance of buildings ................. 7

5.5 BAC efficiency class ..........................................................................................................................................................................21

5.6 BAC and TBM functions assigned to the BAC efficiency classes ................................................................22

5.7 Applying BAC for EnMS and maintaining BAC energy efficiency .............................................................32

5.7.1 General...................................................................................................................................................................................32

5.7.2 Applying BAC for EnMS ...........................................................................................................................................32

5.7.3 Maintaining BAC energy efficiency ...............................................................................................................32

6 Method 1 - Detailed calculation procedure of the BAC contribution to the energy

performance of buildings (detailed method) ......................................................................................................................33

6.1 Output data .............................................................................................................................................................................................33

6.2 Calculation time intervals ...........................................................................................................................................................34

6.3 Input data - Source of data .........................................................................................................................................................35

6.4 Calculation procedure ....................................................................................................................................................................35

6.4.1 Applicable calculation time interval ............................................................................................................35

6.4.2 Energy performance calculation .....................................................................................................................35

7 Method 2 - Factor based calculation procedure of the BAC impact on the energy

performance of buildings (BAC factor method) ................................................................................................................38

7.1 Output data .............................................................................................................................................................................................38

7.2 Calculation time interval .............................................................................................................................................................38

7.3 Calculation procedure — Energy calculation ............................................................................................................39

7.3.1 General...................................................................................................................................................................................39

7.3.2 BAC efficiency factor values ................................................................................................................................40

7.3.3 Application of the BAC efficiency factors .................................................................................................41

8 Simplified input data correlations ..................................................................................................................................................42

9 Quality control .....................................................................................................................................................................................................42

10 Compliance check .............................................................................................................................................................................................42

Annex A (informative) BAC efficiency factors...........................................................................................................................................43

Annex B (normative) Minimum BAC function type requirements .....................................................................................48

Annex C (informative) Determination of the BAC efficiency factors ................................................................................52

Annex D (informative) Examples of how to use the BAC function list of ISO 16484-3 to

describe functions from this document ....................................................................................................................................70

Annex E (informative) Applying BAC for EnMS specified in ISO 50001:2018 .........................................................73

Annex F (informative) Maintain BAC energy efficiency .................................................................................................................87

Annex G (informative) Control accuracy ........................................................................................................................................................91

© ISO 2021 – All rights reserved iii
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ISO/FDIS 52120-1:2021(E)

Bibliography .............................................................................................................................................................................................................................92

iv © ISO 2021 – All rights reserved
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ISO/FDIS 52120-1:2021(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 of 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 the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 205, Building environment design, in

collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/

TC 247, Building Automation, Controls and Building Management, in accordance with the Agreement on

technical cooperation between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 52120 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO 2021 – All rights reserved v
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ISO/FDIS 52120-1:2021(E)
Introduction

This document belongs to the family of standards aimed at international harmonization of the

methodology for the assessment of the energy performance of buildings. Throughout, this group of

standards is referred to as a “set of, called “EPB set of standards”.

All EPB standards follow specific rules to ensure overall consistency, unambiguity and transparency.

This document is clearly identified in the modular structure developed to ensure a transparent and

coherent set of EPB standards, as set out in ISO 52000-1, the overarching EPB standard. BAC (building

automation and control) is identified in the modular structure as technical building system M10.

However, other International Standards issued by ISO TC 205 deal with control accuracy, control

functions and control strategies using standards communications protocol (these last standards do not

belong to the set of EPB standards).

To avoid a duplication of calculation due to the BAC (avoid double impact), no calculation is done in a

BAC EPB standard set, but in each underlying standard of the set of EPB standards (from M1 to M9 in

the modular structure), an identifier developed and present in the M10 covered by this document is

used where appropriate. This way of interaction is described in detail in ISO/TR 52000-2, the Technical

Report accompanying ISO 52000-1. As consequence, the concept of a normative template for specific

(national) choices in Annex A, and Annex B with informative default choices, as commonly used in the

set of EPB standards is not applicable for this document.

The main target groups of this document are all the users of the set of EPB set of standards (e.g.

architects, engineers, regulators).

Further target groups are parties wanting to motivate their assumptions by classifying the building

energy performance for a dedicated building stock.
[5]

More information is provided in the Technical Report accompanying this document (ISO/TR 52120-2 ).

NOTE 1 Table 1 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.

NOTE 2 In ISO/TR 52000-2 the same table can be found, with, for each module, the numbers of the relevant

EPB standards and accompanying technical reports that are published or in preparation.

NOTE 3 The modules represent EPB standards, although one EPB standard can cover more than one module

and one module can be covered by more than one EPB standard, for instance a simplified and a detailed method

respectively. See also Clause 2 and Tables A.1 and B.1.

Table 1 — Position of this document (in casu M10–4,5,6,7,8,9,10), within the modular structure

of the set of EPB standards
Over-arch- Building Technical building system
ing (as such)
sub1 M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11
1 General General General
The shaded modules are not applicable.
vi © ISO 2021 – All rights reserved
Submodule
Descriptions
Descriptions
Descriptions
Heating
Cooling
Ventilation
Humidification
Dehumidification
Domestic hot
waters
Lighting
Building automa-
tion and control
PV, wind, etc.
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ISO/FDIS 52120-1:2021(E)
Table 1 (continued)
Over-arch- Building Technical building system
ing (as such)
sub1 M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11
Common
terms and
definitions; Building ener-
2 Needs
symbols, gy needs
units and
subscripts
(Free) indoor
Maximum
conditions
3 Application load and
without sys-
power
tems
Ways to ex- Ways to ex- Ways to ex-
4 press energy press energy press energy x
performance performance performance
Building
Heat transfer
functions Emission and
5 by transmis- x
and building control
sion
boundaries
Building Heat transfer
occupancy by infiltration Distribution
6 x
and operating and ventila- and control
conditions tion
Aggregation
of energy
Internal heat Storage and
7 services and x
gains control
energy car-
riers
Building par- Solar heat Generation
8 x
titioning gains and control
Load dis-
Calculated Building dy-
patching and
9 energy per- namics (ther- x
operating
formance mal mass)
conditions
Measured Measured Measured
10 energy per- energy perfor- energy per- x
formance mance formance
11 Inspection Inspection Inspection
Ways to ex-
12 press indoor BMS
comfort
External
13 environment
conditions
Economic
calculation
The shaded modules are not applicable.
© ISO 2021 – All rights reserved vii
Submodule
Descriptions
Descriptions
Descriptions
Heating
Cooling
Ventilation
Humidification
Dehumidification
Domestic hot
waters
Lighting
Building automa-
tion and control
PV, wind, etc.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 52120-1:2021(E)
Energy performance of buildings — Contribution
of building automation and controls and building
management —
Part 1:
General framework and procedures
1 Scope
This document specifies:

— a structured list of control, building automation and technical building management functions which

contribute to the energy performance of buildings; functions have been categorized and structured

according to building disciplines and building automation and control (BAC);

— a method to define minimum requirements or any specification regarding the control, building

automation and technical building management functions contributing to energy efficiency of a

building to be implemented in building of different complexities;

— a factor-based method to get a first estimation of the effect of these functions on typical buildings

types and use profiles;
— detailed methods to assess the effect of these functions on a given building.
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.

ISO 50001:2018, Energy management systems — Requirements with guidance for use

ISO 52000-1:2017, Energy performance of buildings — Overarching EPB assessment — Part 1: General

framework and procedures

ISO 7345:2018, Thermal performance of buildings and building components — Physical quantities and

definitions
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 7345:2018, in ISO 52000-1:2017

and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
© ISO 2021 – All rights reserved 1
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ISO/FDIS 52120-1:2021(E)
3.1
auxiliary energy

electrical energy used by technical building systems (3.14) to support energy transformation to satisfy

energy needs

Note 1 to entry: This includes energy for fans, pumps, electronics, etc. Electrical energy input to the ventilation

system for air transport and heat recovery is not considered as auxiliary energy, but as energy used for

ventilation.

Note 2 to entry: In ISO 9488 the energy used for pumps and valves is called “parasitic energy”.

[SOURCE: ISO 13612-2:2014, 3.3, modified — Note 3 to entry was removed.]
3.2
building automation and control
BAC

products, software, and engineering services for automatic controls, monitoring and optimization,

human intervention and management to achieve energy-efficient, economical, and safe operation of

building services equipment
[SOURCE: ISO 52000-1:2017, 3.4.4, modified – The term BAC was added.]
3.3
building automation and control system
BACS

system, comprising all products, software and engineering services for automatic controls (including

interlocks), monitoring, optimization, for operation, human intervention, and management to achieve

energy-efficient, economical, and safe operation of building services
Note 1 to entry: BACS is also referred to as BMS (building management system).

Note 2 to entry: The use of the word ‘control’ does not imply that the system or device is restricted to control

functions (3.5). Processing of data and information is possible.

Note 3 to entry: If a building control system, building management (3.4) system, or building energy management

system complies with the requirements of the ISO 16484 series, it should be designated as a building automation

and control system (BACS).

Note 4 to entry: Building services are divided in technical, infrastructural and financial building services and

energy management is part of technical building management (3.13).
Note 5 to entry: Building energy management system is part of a BMS.

Note 6 to entry: The building energy management system comprises data collection, logging, alarming,

reporting, and analysis of energy usage, etc. The system is designed to reduce the energy consumption, improve

the utilization, increase the reliability, and predict the performance of the technical building systems (3.14), as

well as optimize energy usage and reducing its cost.

[SOURCE: ISO 16484-2:2004, 3.31, modified – Notes to entry 1, 4, 5 and 6 have been added.]

3.4
building management

totality of services involved in the management operation and monitoring of buildings (including plants

and installations)

Note 1 to entry: Building management can be assigned as part of facility management.

[SOURCE: CEN/TS 15379:2009, 3.4, modified – Second part of the definition became Note 1 to entry.]

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ISO/FDIS 52120-1:2021(E)
3.5
control function
BAC (3.2) effect of programs and parameters

Note 1 to entry: BAC functions are referred to as control functions, I/O, processing, optimization, management

and operator functions. They are listed in the BAC FL (function list) for a specification of work.

Note 2 to entry: Function is a program unit that delivers exactly one data element, which can be a multiple value

(i.e. an array or a structure). Functions can be an operand in a program as described in EN 61131–3.

3.6
delivered energy

energy, expressed per energy carrier (3.7), supplied to the technical building systems (3.14) through the

assessment boundary, to satisfy the uses taken into account or to produce the exported energy

Note 1 to entry: Delivered energy can be calculated for defined energy uses or it can be measured.

[SOURCE: ISO 52000-1:2017, 3.4.6]
3.7
energy carrier

substance or phenomenon that can be used to produce mechanical work or heat or to operate chemical

or physical processes
[SOURCE: ISO 52000-1:2017, 3.4.9]
3.8
energy need for heating and cooling

heat to be delivered to or extracted from a thermally conditioned space to maintain the intended space

temperature conditions during a given period of time

Note 1 to entry: The energy need can include additional heat transfer resulting from non-uniform temperature

distribution and non-ideal temperature control, if they are taken into account by increasing (decreasing) the

effective temperature for heating (cooling) and not included in the heat transfer due to the heating (cooling)

system.

[SOURCE: ISO 52000-1:2017, 3.4.13 — Note 1 to entry added and the term was originally "energy need

for heating or cooling".]
3.9
energy efficiency

ratio or other quantitative relationship between an output of performance, service, goods or energy,

and an input of energy

EXAMPLE Efficiency conversion; energy required/energy used; output/input; theoretical energy used to

operate/energy used to operate.

Note 1 to entry: Both input and output need to be clearly specified in quantity and quality, and be measurable.

[SOURCE: ISO 50001:2018, 3.5.3 modified—- "commodities" was removed from the definition and the

example has been modified.]
3.10
integrated function

BAC (3.2) effect of programs, shared data points and parameters for multi-discipline interrelationships

between various building services and technologies
© ISO 2021 – All rights reserved 3
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ISO/FDIS 52120-1:2021(E)
3.11
measured energy performance
energy performance based on measured amounts of delivered and exported energy

Note 1 to entry: The measured rating is the weighted sum of all energy carriers (3.7) used by the building, as

measured by meters or derived from measured energy by other means. It is a measure of the in-use performance

of the building after correction or extrapolation. This is particularly relevant to certification of actual energy

performance.
Note 2 to entry: Also known as “operational rating”.

[SOURCE: ISO 52000-1:2017, 3.5.16, modified — "weighted measured amounts" has been replaced by

"measured amounts" in the definition and "energy performance" has been replaced by "rating".]

3.12
thermally activated building system
TABS

massive building fabric actively heated or cooled by integrated air- or water-based systems

3.13
technical building management
TBM

process(es) and services related to operation and management of buildings and technical building system

(3.14) through the interrelationships between the different disciplines and trades

Note 1 to entry: The disciplines and trades comprise all technical building services for the purpose of optimized

maintenance and energy consumption.

EXAMPLE Optimization of buildings through interrelationships ranging from heating, ventilation and air

conditioning (HVAC), to lighting and day lighting, to life safety and security, to electric power systems and energy

monitoring and metering, to services, including communications and maintenance and to management.

[SOURCE: ISO 52127-1:2021, 3.2]
3.14
technical building system

technical equipment for heating, cooling, ventilation, humidification, dehumidification, domestic hot

water, lighting and electricity production

Note 1 to entry: A technical building system can refer to one or to several building services (e.g. heating, heating

and DHW).

Note 2 to entry: A technical building system is composed of different subsystems.

Note 3 to entry: Electricity production can include cogeneration and photovoltaic systems.

[SOURCE: ISO 52000-1:2017, 3.3.13, modified — The phrase "building automation and control" was

deleted from the definition.]
3.15
EPB standard

standard that complies with the requirements given in ISO 52000-1, CEN/TS 16628 and CEN/TS 16629

Note 1 to entry: These three basic EPB documents were developed under a mandate given to CEN by the European

Commission and the European Free Trade Association (Mandate M/480), and support essential requirements of

EU Directive 2010/31/EC on the energy performance of buildings (EPBD). Several EPB standards and related

[5] [6]

documents are developed or revised under the same mandate. CEN/TS 16628 and CEN/TS 16629 are

available as N-documents in ISO/TC 163 and ISO/TC 205.

[SOURCE: ISO 52000-1:2017, 3.5.14, modified — The last sentence of the Note 1 to entry has been added.]

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ISO/FDIS 52120-1:2021(E)
4 Symbols, subscripts and abbreviated terms
4.1 Symbols

For the purposes of this document, the symbols given in ISO 52000-1 and Table 2 apply.

Table 2 — Symbols
Symbol Quantity Unit
a normalized level, e.g. occupancy or gains -
mean part load -
Φ heat flow rate, thermal power kW
4.2 Subscripts

For the purposes of this document, the subscript given in ISO 52000-1:2017, Clause 4 and Annex C and

the specific subscripts listed in Table 3 apply.

NOTE Relevant subscripts already given in ISO 52000-1 are included if necessary for the understanding of

this document.
Table 3 — Subscripts
Subscript Term Subscript Term Subscript Term
amb ambient end end th thermal
BAC building automation r room trans transfer
and control
cor correction ref reference
ctr control set setpoint
DHW domestic hot water sta start
4.3 Abbreviated terms

For the purposes of this document, the abbreviated terms given in ISO 52000-1 and Table 4 apply.

Table 4 — Abbreviated terms
AHU air handling unit
BAC building automation and control
BM building management
COP coefficient of performance
DHW domestic hot water
HVAC heating, ventilation and air conditioning
TABS thermally activated building systems
TBM technical building management
VFD variable flow dependant
VRF variable room flow
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ISO/FDIS 52120-1:2021(E)
5 Description of the method
5.1 Output of the method

This document describes two methods of how to calculate the contribution of building automation and

controls to the energy
...