ISO 18523-1:2016

SLOVENSKI STANDARD
SIST ISO 18523-1:2020
01-junij-2020
Energijske lastnosti stavb - Urniki in pogoji uporabe stavbe, con in prostorov za
izračun rabe energije - 1. del: Nestanovanjske stavbe
Energy performance of buildings -- Schedule and condition of building, zone and space
usage for energy calculation -- Part 1: Non-residential buildings
Performance énergétique des bâtiments -- Plan et conditions d'utilisation des espaces,
zones et bâtiments pour le calcul d'énergie -- Partie 1: Bâtiments non résidentiels
Ta slovenski standard je istoveten z: ISO 18523-1:2016
ICS:
91.040.01 Stavbe na splošno Buildings in general
91.120.10 Toplotna izolacija stavb Thermal insulation of
buildings
SIST ISO 18523-1:2020 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST ISO 18523-1:2020

---------------------- Page: 2 ----------------------
SIST ISO 18523-1:2020
INTERNATIONAL ISO
STANDARD 18523-1
First edition
2016-11-15
Energy performance of buildings —
Schedule and condition of building,
zone and space usage for energy
calculation —
Part 1:
Non-residential buildings
Performance énergétique des bâtiments — Plan et conditions
d’utilisation des espaces, zones et bâtiments pour le calcul
d’énergie —
Partie 1: Bâtiments non résidentiels
Reference number
ISO 18523-1:2016(E)
©
ISO 2016

---------------------- Page: 3 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved

---------------------- Page: 4 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Contents
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Framework of the schedule and condition for building energy calculation . 7
4.1 Indispensable schedules . 7
4.2 Daily schedule . 8
4.3 Division of year and daily, weekly, monthly, seasonal and annual allocations of daily
schedule . 10
5 Conditions for energy calculation included in the schedule and condition of building,
zone and space usage . 13
5.1 Energy needs and uses . 13
5.2 Condition . 13
5.2.1 General information on occupancy and usage . 13
5.2.1.1 Occupancy density . 13
5.2.1.2 Simulataneous usage ratio of a set of zones and spaces . 14
5.2.2 Operation of technical building systems and requirement for the services . 14
5.2.2.1 Space heating and cooling . 14
5.2.2.2 Ventilation for conditioned zone or space . 14
5.2.2.3 Lighting . 15
5.2.2.4 Domestic hot water . 15
5.2.2.5 Ventilation for unconditioned zone or space . 15
5.2.3 Internal heat gains . 16
5.2.3.1 Person . 16
5.2.3.2 Lighting . 16
5.2.3.3 Appliances . 16
6 Category of building, zone and space . 17
6.1 General . 17
6.2 Category of building . 17
6.3 Category of space or zone . 17
Annex A (informative) Format of daily schedule . 19
Annex B (informative) A set of annual schedules by daily allocation of daily schedules . 21
Annex C (informative) Categories of space and zone . 27
Annex D (informative) A set of daily schedules for categories of space and zone . 35
Annex E (informative) Examples of building . 207
Bibliography . 252
© ISO 2016 – All rights reserved iii

---------------------- Page: 5 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
iv © ISO 2016 – All rights reserved

---------------------- Page: 6 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(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 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 the following
URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 163, Thermal Performance and energy use in the
built environment.
© ISO 2016 – All rights reserved v

---------------------- Page: 7 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Introduction
There is a strong need to improve the environment to make the evaluation of energy performance of
buildings more reliable and practical, so that energy efficiency of buildings is improved by referring to
the evaluation results. To realize such environment, one important standard on how to prescribe the
ways of using buildings has been missed, even though many assumptions on the building usage have
appeared in standards relevant to the energy calculation.
This document prescribes the indispensable information on the formats to express the usage of
building, zone and space in energy calculation for non‐residential buildings.
vi © ISO 2016 – All rights reserved

---------------------- Page: 8 ----------------------
SIST ISO 18523-1:2020
INTERNATIONAL STANDARD ISO 18523-1:2016(E)

Energy performance of buildings — Schedule and condition of
building, zone and space usage for energy calculation —
Part 1:
Non-residential buildings
1 Scope
This document specifies the formats to present schedule and condition of building, zone and space
usage, which is to be referred to as input data of energy calculations for non‐residential buildings.
The schedule and condition include schedules of occupancy, operation of technical building systems,
ventilation rate, hot water usage and internal heat gains due to occupancy, lighting and equipment.
This document also gives categories of building, zone and space according to differentiating schedule
and condition.
Depending on necessary minuteness of the energy calculation, different levels of schedule and condition
from the view point of time and space averaging are specified.
The values and categories for the schedule and condition are given in annexes for more information for
the application when the users of this document do not have detailed information on the values and
categories for the schedule and condition.
The schedule and condition in this document is basically different from assumptions in order to
determine the size of technical building systems in the process of design, where possible largest values
are to be assumed. Instead, most usual and average values, which are assumed for the building energy
calculation, are dealt with in this document.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1 Space
3.1.1
space
part of a room, a room or group of adjacent rooms with assumed uniform properties for all considered
types of zones (3.1.2)
© ISO 2016 – All rights reserved 1

---------------------- Page: 9 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.1.2
zone
part of a building (3.1.3) consisting of (part of) one or more spaces with assumed uniform properties
related to a specific service or service component, or (in absence of a service) assumed uniform indoor
environmental conditions
3.1.3
building
construction as a whole, including its envelope and all technical building systems (3.3.5), where energy
is used to condition the indoor thermal environment and to provide domestic hot water, lighting
according to visual tasks and other services related to the use of the building
3.1.4
thermally conditioned space
thermally conditioned zone
heated and/or cooled space (3.1.1) or zone (3.1.2)
3.1.5
thermally unconditioned space
thermally unconditioned zone
space (3.1.1) or zone (3.1.2) that is not heated nor cooled
3.2 Schedule
3.2.1
schedule
information on condition(s) of usage of building (3.1.3), zone (3.1.2) or space (3.1.1) throughout a cycle
of period, such as day, week, month, season and year
3.2.2
daily schedule
conditions (3.3.1) of occupancy (3.3.2), service system operations, requirement for the functions of the
service systems and internal heat gains in each time of a day
3.2.3
daily schedule with hourly conditions
set of hourly conditions (3.3.1) of occupancy (3.3.2), service system operations, requirement for the
functions of the service systems and internal heat gains in a day
3.2.4
set of daily schedules
complete set of daily schedules representing usage of a category of building (3.1.3), zone (3.1.2) or space
(3.1.1) in one year
3.2.5
daily operating hours
hours when service system is operated or the length of the hours
3.2.6
annual operating hours
total length of hours in the standard year (3.2.15) when technical building system (3.3.5) is operated
2 © ISO 2016 – All rights reserved

---------------------- Page: 10 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.2.7
annual schedule
allocation of daily schedule(s) (3.2.2) for one year
Note 1 to entry: Division of the year can be selected from 365 days, 53 weeks, 12 months, seasons or no division [a
set of daily schedules (3.2.4) is uniformly applied throughout the year].
3.2.8
seasonal schedule
allocation of daily schedule(s) (3.2.2) to each season of the year
3.2.9
monthly schedule
allocation of daily schedule(s) (3.2.2) to each month of the year
3.2.10
weekly schedule
allocation of daily schedule(s) (3.2.2) to each week of the year
3.2.11
whole set of annual schedules
complete set of annual schedules (3.2.7) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.12
whole set of seasonal schedules
complete set of seasonal schedules (3.2.8) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.13
whole set of monthly schedules
complete set of monthly schedules (3.2.9) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.14
number of days in one year
total number of days, which shall be 365
3.2.15
standard year
selected year, of which number of day has to be 365 and arrangement of weekdays, weekends and
holidays are referred in weekly, monthly, seasonal and annual schedules (3.2.7)
3.3 Parameters for conditions of building, zone and space usage
3.3.1
condition
status of occupancy (3.3.2), operation of service systems, requirement for the functions of the technical
building systems (3.3.5) and internal heat gains
3.3.2
occupancy
presence of users in building (3.1.3), zone (3.1.2) or space (3.1.1)
© ISO 2016 – All rights reserved 3

---------------------- Page: 11 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.3.3
occupancy density
number of present user in building (3.1.3), zone (3.1.2) or space per unit floor area of the space (3.1.1)
Note 1 to entry: Occupancy density is used mainly for the calculations for space heating/cooling and ventilation.
3.3.4
simultaneous usage ratio (of a set of spaces)
ratio of the number of zones (3.1.2) or spaces (3.1.1), which belong to a group of zones and spaces and
are occupied or used at the time, to the total number of zones or spaces in the group
Note 1 to entry: This concept is applied to a group of zones or spaces of the same category, such as a group of
guest rooms in hotels, a series of personal office rooms in office buildings, etc.
3.3.5
technical building system
all energy‐using or energy‐distributing components in a building (3.1.3) that are operated to support
the occupant or process functions housed therein
Note 1 to entry: These include HVAC, domestic hot water, illumination, transportation, laundering or similar
functions.
3.3.6
luminaire
apparatus which distributes, filters or transforms the light transmitted from one or more lamps
Note 1 to entry: Except for the lamps themselves, all the parts necessary for fixing and protecting the lamps and,
where necessary, circuit auxiliaries together with the means for connecting them to the electric supply
[SOURCE: CIE S 017/E: 2011, 17–707]
3.3.7
in operation
status of a technical building system (3.3.5), in which the technical building system can function to
satisfy the requirement for the technical building system, such as the set‐point temperature and the
maintained average illuminance (3.3.9)
Note 1 to entry: When the requirement is satisfied without its functioning, the technical building system stands by.
3.3.8
out of operation
status of a technical building system (3.3.5) in which the technical building system cannot function
regardless of the relevant requirement or due to inexistence of any requirement for the technical
building system
3.3.9
maintained average illuminance
value below which the average illuminance over the specified surface is not allowed to fall, lux
[SOURCE: CIE S 017/E: 2011, 17–750]
4 © ISO 2016 – All rights reserved

---------------------- Page: 12 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.3.10
height of the working plane
height of the plane, on which the assumed visual task is done, from the floor
Note 1 to entry: It is expressed in metres (m).
3.3.11
demand control ventilation
ventilation, of which rate is controlled according to the necessity of the ventilation, such as to the
emission rate of target pollutant
3.3.12
energy need for space heating and cooling
heat to be delivered to or extracted from a conditioned space (3.1.1) to maintain the intended
temperature and/or humidity conditions during a given period of time
3.3.13
energy use for space heating and cooling
energy input to the heating and cooling system to satisfy the energy need for space heating and cooling
(3.3.12)
3.3.14
energy need for ventilation for outdoor air supply
work by electric motors to convey outdoor air to satisfy ventilation requirement
3.3.15
energy use for ventilation for outdoor air supply
energy input to the ventilation system to satisfy the energy need for ventilation for outdoor air supply
(3.3.14)
3.3.16
energy need for domestic hot water
heat to be delivered to the needed amount of domestic hot water to raise its temperature from the cold
network temperature to the prefixed delivery temperature at the delivery point
3.3.17
energy use for domestic hot water
energy input to the domestic hot water system to satisfy the energy need for domestic hot water (3.3.16)
3.3.18
energy use for lighting
energy consumed by luminaires (3.3.6) and lamps
3.3.19
energy use for transportation
energy consumed by equipment for transportation, such as elevators
3.3.20
energy calculation
calculation of energy uses for technical building systems (3.3.5)

© ISO 2016 – All rights reserved 5

---------------------- Page: 13 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.4 Descriptions for daily schedule
3.4.1
reference ventilation requirement
most probable estimation of outdoor air supply (in volume flow rate per unit floor area or in air change
per hour) to the space (3.1.1) or zone (3.1.2) in compliance with relevant regulation
3.4.2
reference domestic hot water usage
maximum hourly service hot water usage by users of the space (3.1.1) or zone (3.1.2) in volume flow
rate per person, in volume flow rate per unit floor area or in volume flow rate per bed
Note 1 entry: The volume flow rate is calculated with the assumption on hot water temperature.
3.4.3
total daily usage of domestic hot water
total volume of service hot water usage in one day in volume per person, in volume per unit floor area
or in volume per bed
Note 1 entry: The volume flow rate is calculated with the assumption on hot water temperature.
3.4.4
reference occupancy density
maximum hourly occupancy density (3.3.3) of the space (3.1.1) or zone (3.1.2) in person per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), occupancy density at the time can be calculated.
3.4.5
reference heat gain due to person
maximum hourly total (sensitive and latent) heat gain due to person inside the room or zone (3.1.2) in
watt per unit floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), heat gain due to person at the time can be calculated.
3.4.6
reference sensible heat gain due to person
maximum hourly sensible heat gain due to person inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), sensible heat gain due to person at the time can be
calculated.
3.4.7
reference latent heat gain due to person
maximum hourly latent heat gain due to person inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), latent heat gain due to person at the time can be
calculated.
6 © ISO 2016 – All rights reserved

---------------------- Page: 14 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.4.8
reference heat gain due to lighting
maximum hourly sensible heat gain due to lighting inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios, heat gain due to lighting at the time can be calculated.
3.4.9
reference heat gain due to appliances
maximum hourly total (sensible and latent) heat gain due to appliances inside the room or zone (3.1.2)
in watt per unit floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), heat gain due to appliances at the time can be
calculated.
3.4.10
reference sensible heat gain due to appliances
maximum hourly sensible heat gain due to appliances inside the room or zone (3.1.2) in watt per unit
floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), sensible heat gain due to appliances at the time can be
calculated.
3.4.11
reference latent heat gain due to appliances
maximum hourly latent heat gain due to appliances inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), latent heat gain due to appliances at the time can be
calculated.
3.4.12
hourly ratio
ratio of hourly value of parameters to their reference value
Note 1 to entry: Multiplying hourly ratios by the reference value, hourly values of the parameter can be calculated.
4 Framework of the schedule and condition for building energy calculation
4.1 Indispensable schedules
The building energy calculations are characterized by the division number of the year, the calculation
period or the calculation interval. Each calculation method has its appropriate calculation interval
according to characteristics of the target physical phenomenon (for example, unsteadiness) and
minuteness of the calculation responding to changes of climatic condition, occupants’ behaviour,
behaviour of service systems and so on.
Due to the variety of calculation method, there is a variety of form of the schedule and condition of
building, zone and space usage. Nevertheless, there is a fundamental unit of form, daily schedule, which
shall be included in forms for the schedule and condition. The daily schedule corresponds to the
minimum cycle of building, zone and space usage, and also of climatic and solar condition.
Some nations adopt so called “monthly calculation” for space heating and cooling energy needs and
uses, taking monthly variation of outdoor temperature and solar irradiance into consideration. One
daily schedule for business day and the number of the business days is given to each month for each
type of building, zone and space. Monthly means of outdoor air condition (for example, temperature)
© ISO 2016 – All rights reserved 7

---------------------- Page: 15 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
and solar irradiance for different orientations and inclinations are given for the calculation. The
expression of the daily schedule varies from detailed expression with hourly values to simplified
expression such as daily mean values and the like. Additional schedule for closing day can be given in a
simplified way such as only with daily mean values.
Similarly, in so called “seasonal calculation”, one daily schedule for business day and the number of the
business days for each season are given to each season for each type of building, zone and space, and
the calculation is done with seasonal mean values for climatic condition.
For the calculation of more steady phenomena, so called “annual calculation” can work if seasonal
change of solar condition is integrated throughout the year and condensed in specific coefficients.
Nevertheless, one daily schedule for business day and the number of annual business days are
necessary. Additional daily schedule for closing day can be given.
For the calculation of lighting, monthly or yearly calculation is mainly used, but unsteady aspects of
lighting still can be dealt with. In the calculation for lighting, when input parameters such as operating
hours with and without daylight are prescribed, daily schedule as described in the column (2) of Table 1
and annual schedule by monthly allocation of daily schedules (Table 5) or annual schedule without
division of the year (Table 7) should be explicitly given, so that the operating hours for light is well
harmonized with those for other technical systems.
Therefore, for each category of building, zone and space, necessary number of daily schedules (e.g. two
daily schedules for business day and closing day), and one of annual, seasonal, monthly and weekly
schedules shall be given in order that the daily schedules are allocated for the year.
4.2 Daily schedule
The daily schedule shall contain hourly values of condition for one day or shall contain condensed or
simplified information on conditions for the day. With some assumptions, the hourly detailed values can
be generated from condensed or simplified information and used even for detailed calculation. If
necessary, multiple daily schedules representing different daily patterns of usage should be given such
as for weekdays, weekends and holidays. The number of daily schedules depends on minuteness of the
schedule and condition, as well as on the category of building, zone and space under consideration.
The conditions described in the daily schedule are grouped into the following three categories:
a) general information on occupancy and usage of building, zone and space;
b) operation of technical building systems and requirement for their services;
c) internal heat gains.
The basic structure of daily schedule is shown in Table 1.
8 © ISO 2016 – All rights reserved

---------------------- Page: 16 ----------------------
SIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Table 1 — Framework of daily schedule for building, zone or space
(1) description by hourly (2) condensed or simplified
Parameters and their categories
values for 0 h to 24 h description
a) General Occupancy density Hourly occupancy density Times of start and end of
information on occupancy or total hours of
occupancy and occupancy, and average occupancy
usage density during usage
Simultaneous Hourly simultaneous usage Mean simultaneous usage ratio
usage ratio of a set ratio during usage
of rooms
b) Operation of Space heating Hourly status of space heating Times of start and end of operation,
technical and/or cooling and/or cooling system (in or or total hours of operation
building s
...

SLOVENSKI STANDARD
oSIST ISO 18523-1:2020
01-marec-2020
Energetska učinkovitost stavb - Načrt in pogoji uporabe prostorov, con in stavb za
izračun energije - 1. del: Nestanovanjske stavbe
Energy performance of buildings -- Schedule and condition of building, zone and space
usage for energy calculation -- Part 1: Non-residential buildings
Performance énergétique des bâtiments -- Plan et conditions d'utilisation des espaces,
zones et bâtiments pour le calcul d'énergie -- Partie 1: Bâtiments non résidentiels
Ta slovenski standard je istoveten z: ISO 18523-1:2016
ICS:
91.120.10 Toplotna izolacija stavb Thermal insulation of
buildings
oSIST ISO 18523-1:2020 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST ISO 18523-1:2020

---------------------- Page: 2 ----------------------
oSIST ISO 18523-1:2020
INTERNATIONAL ISO
STANDARD 18523-1
First edition
2016-11-15
Energy performance of buildings —
Schedule and condition of building,
zone and space usage for energy
calculation —
Part 1:
Non-residential buildings
Performance énergétique des bâtiments — Plan et conditions
d’utilisation des espaces, zones et bâtiments pour le calcul
d’énergie —
Partie 1: Bâtiments non résidentiels
Reference number
ISO 18523-1:2016(E)
©
ISO 2016

---------------------- Page: 3 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved

---------------------- Page: 4 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Contents
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Framework of the schedule and condition for building energy calculation . 7
4.1 Indispensable schedules . 7
4.2 Daily schedule . 8
4.3 Division of year and daily, weekly, monthly, seasonal and annual allocations of daily
schedule . 10
5 Conditions for energy calculation included in the schedule and condition of building,
zone and space usage . 13
5.1 Energy needs and uses . 13
5.2 Condition . 13
5.2.1 General information on occupancy and usage . 13
5.2.1.1 Occupancy density . 13
5.2.1.2 Simulataneous usage ratio of a set of zones and spaces . 14
5.2.2 Operation of technical building systems and requirement for the services . 14
5.2.2.1 Space heating and cooling . 14
5.2.2.2 Ventilation for conditioned zone or space . 14
5.2.2.3 Lighting . 15
5.2.2.4 Domestic hot water . 15
5.2.2.5 Ventilation for unconditioned zone or space . 15
5.2.3 Internal heat gains . 16
5.2.3.1 Person . 16
5.2.3.2 Lighting . 16
5.2.3.3 Appliances . 16
6 Category of building, zone and space . 17
6.1 General . 17
6.2 Category of building . 17
6.3 Category of space or zone . 17
Annex A (informative) Format of daily schedule . 19
Annex B (informative) A set of annual schedules by daily allocation of daily schedules . 21
Annex C (informative) Categories of space and zone . 27
Annex D (informative) A set of daily schedules for categories of space and zone . 35
Annex E (informative) Examples of building . 207
Bibliography . 252
© ISO 2016 – All rights reserved iii

---------------------- Page: 5 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
iv © ISO 2016 – All rights reserved

---------------------- Page: 6 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(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 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 the following
URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 163, Thermal Performance and energy use in the
built environment.
© ISO 2016 – All rights reserved v

---------------------- Page: 7 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Introduction
There is a strong need to improve the environment to make the evaluation of energy performance of
buildings more reliable and practical, so that energy efficiency of buildings is improved by referring to
the evaluation results. To realize such environment, one important standard on how to prescribe the
ways of using buildings has been missed, even though many assumptions on the building usage have
appeared in standards relevant to the energy calculation.
This document prescribes the indispensable information on the formats to express the usage of
building, zone and space in energy calculation for non‐residential buildings.
vi © ISO 2016 – All rights reserved

---------------------- Page: 8 ----------------------
oSIST ISO 18523-1:2020
INTERNATIONAL STANDARD ISO 18523-1:2016(E)

Energy performance of buildings — Schedule and condition of
building, zone and space usage for energy calculation —
Part 1:
Non-residential buildings
1 Scope
This document specifies the formats to present schedule and condition of building, zone and space
usage, which is to be referred to as input data of energy calculations for non‐residential buildings.
The schedule and condition include schedules of occupancy, operation of technical building systems,
ventilation rate, hot water usage and internal heat gains due to occupancy, lighting and equipment.
This document also gives categories of building, zone and space according to differentiating schedule
and condition.
Depending on necessary minuteness of the energy calculation, different levels of schedule and condition
from the view point of time and space averaging are specified.
The values and categories for the schedule and condition are given in annexes for more information for
the application when the users of this document do not have detailed information on the values and
categories for the schedule and condition.
The schedule and condition in this document is basically different from assumptions in order to
determine the size of technical building systems in the process of design, where possible largest values
are to be assumed. Instead, most usual and average values, which are assumed for the building energy
calculation, are dealt with in this document.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1 Space
3.1.1
space
part of a room, a room or group of adjacent rooms with assumed uniform properties for all considered
types of zones (3.1.2)
© ISO 2016 – All rights reserved 1

---------------------- Page: 9 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.1.2
zone
part of a building (3.1.3) consisting of (part of) one or more spaces with assumed uniform properties
related to a specific service or service component, or (in absence of a service) assumed uniform indoor
environmental conditions
3.1.3
building
construction as a whole, including its envelope and all technical building systems (3.3.5), where energy
is used to condition the indoor thermal environment and to provide domestic hot water, lighting
according to visual tasks and other services related to the use of the building
3.1.4
thermally conditioned space
thermally conditioned zone
heated and/or cooled space (3.1.1) or zone (3.1.2)
3.1.5
thermally unconditioned space
thermally unconditioned zone
space (3.1.1) or zone (3.1.2) that is not heated nor cooled
3.2 Schedule
3.2.1
schedule
information on condition(s) of usage of building (3.1.3), zone (3.1.2) or space (3.1.1) throughout a cycle
of period, such as day, week, month, season and year
3.2.2
daily schedule
conditions (3.3.1) of occupancy (3.3.2), service system operations, requirement for the functions of the
service systems and internal heat gains in each time of a day
3.2.3
daily schedule with hourly conditions
set of hourly conditions (3.3.1) of occupancy (3.3.2), service system operations, requirement for the
functions of the service systems and internal heat gains in a day
3.2.4
set of daily schedules
complete set of daily schedules representing usage of a category of building (3.1.3), zone (3.1.2) or space
(3.1.1) in one year
3.2.5
daily operating hours
hours when service system is operated or the length of the hours
3.2.6
annual operating hours
total length of hours in the standard year (3.2.15) when technical building system (3.3.5) is operated
2 © ISO 2016 – All rights reserved

---------------------- Page: 10 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.2.7
annual schedule
allocation of daily schedule(s) (3.2.2) for one year
Note 1 to entry: Division of the year can be selected from 365 days, 53 weeks, 12 months, seasons or no division [a
set of daily schedules (3.2.4) is uniformly applied throughout the year].
3.2.8
seasonal schedule
allocation of daily schedule(s) (3.2.2) to each season of the year
3.2.9
monthly schedule
allocation of daily schedule(s) (3.2.2) to each month of the year
3.2.10
weekly schedule
allocation of daily schedule(s) (3.2.2) to each week of the year
3.2.11
whole set of annual schedules
complete set of annual schedules (3.2.7) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.12
whole set of seasonal schedules
complete set of seasonal schedules (3.2.8) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.13
whole set of monthly schedules
complete set of monthly schedules (3.2.9) representing usage of all types of building (3.1.3), zone (3.1.2)
and space (3.1.1), as objects of energy calculation (3.3.20)
3.2.14
number of days in one year
total number of days, which shall be 365
3.2.15
standard year
selected year, of which number of day has to be 365 and arrangement of weekdays, weekends and
holidays are referred in weekly, monthly, seasonal and annual schedules (3.2.7)
3.3 Parameters for conditions of building, zone and space usage
3.3.1
condition
status of occupancy (3.3.2), operation of service systems, requirement for the functions of the technical
building systems (3.3.5) and internal heat gains
3.3.2
occupancy
presence of users in building (3.1.3), zone (3.1.2) or space (3.1.1)
© ISO 2016 – All rights reserved 3

---------------------- Page: 11 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.3.3
occupancy density
number of present user in building (3.1.3), zone (3.1.2) or space per unit floor area of the space (3.1.1)
Note 1 to entry: Occupancy density is used mainly for the calculations for space heating/cooling and ventilation.
3.3.4
simultaneous usage ratio (of a set of spaces)
ratio of the number of zones (3.1.2) or spaces (3.1.1), which belong to a group of zones and spaces and
are occupied or used at the time, to the total number of zones or spaces in the group
Note 1 to entry: This concept is applied to a group of zones or spaces of the same category, such as a group of
guest rooms in hotels, a series of personal office rooms in office buildings, etc.
3.3.5
technical building system
all energy‐using or energy‐distributing components in a building (3.1.3) that are operated to support
the occupant or process functions housed therein
Note 1 to entry: These include HVAC, domestic hot water, illumination, transportation, laundering or similar
functions.
3.3.6
luminaire
apparatus which distributes, filters or transforms the light transmitted from one or more lamps
Note 1 to entry: Except for the lamps themselves, all the parts necessary for fixing and protecting the lamps and,
where necessary, circuit auxiliaries together with the means for connecting them to the electric supply
[SOURCE: CIE S 017/E: 2011, 17–707]
3.3.7
in operation
status of a technical building system (3.3.5), in which the technical building system can function to
satisfy the requirement for the technical building system, such as the set‐point temperature and the
maintained average illuminance (3.3.9)
Note 1 to entry: When the requirement is satisfied without its functioning, the technical building system stands by.
3.3.8
out of operation
status of a technical building system (3.3.5) in which the technical building system cannot function
regardless of the relevant requirement or due to inexistence of any requirement for the technical
building system
3.3.9
maintained average illuminance
value below which the average illuminance over the specified surface is not allowed to fall, lux
[SOURCE: CIE S 017/E: 2011, 17–750]
4 © ISO 2016 – All rights reserved

---------------------- Page: 12 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.3.10
height of the working plane
height of the plane, on which the assumed visual task is done, from the floor
Note 1 to entry: It is expressed in metres (m).
3.3.11
demand control ventilation
ventilation, of which rate is controlled according to the necessity of the ventilation, such as to the
emission rate of target pollutant
3.3.12
energy need for space heating and cooling
heat to be delivered to or extracted from a conditioned space (3.1.1) to maintain the intended
temperature and/or humidity conditions during a given period of time
3.3.13
energy use for space heating and cooling
energy input to the heating and cooling system to satisfy the energy need for space heating and cooling
(3.3.12)
3.3.14
energy need for ventilation for outdoor air supply
work by electric motors to convey outdoor air to satisfy ventilation requirement
3.3.15
energy use for ventilation for outdoor air supply
energy input to the ventilation system to satisfy the energy need for ventilation for outdoor air supply
(3.3.14)
3.3.16
energy need for domestic hot water
heat to be delivered to the needed amount of domestic hot water to raise its temperature from the cold
network temperature to the prefixed delivery temperature at the delivery point
3.3.17
energy use for domestic hot water
energy input to the domestic hot water system to satisfy the energy need for domestic hot water (3.3.16)
3.3.18
energy use for lighting
energy consumed by luminaires (3.3.6) and lamps
3.3.19
energy use for transportation
energy consumed by equipment for transportation, such as elevators
3.3.20
energy calculation
calculation of energy uses for technical building systems (3.3.5)

© ISO 2016 – All rights reserved 5

---------------------- Page: 13 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.4 Descriptions for daily schedule
3.4.1
reference ventilation requirement
most probable estimation of outdoor air supply (in volume flow rate per unit floor area or in air change
per hour) to the space (3.1.1) or zone (3.1.2) in compliance with relevant regulation
3.4.2
reference domestic hot water usage
maximum hourly service hot water usage by users of the space (3.1.1) or zone (3.1.2) in volume flow
rate per person, in volume flow rate per unit floor area or in volume flow rate per bed
Note 1 entry: The volume flow rate is calculated with the assumption on hot water temperature.
3.4.3
total daily usage of domestic hot water
total volume of service hot water usage in one day in volume per person, in volume per unit floor area
or in volume per bed
Note 1 entry: The volume flow rate is calculated with the assumption on hot water temperature.
3.4.4
reference occupancy density
maximum hourly occupancy density (3.3.3) of the space (3.1.1) or zone (3.1.2) in person per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), occupancy density at the time can be calculated.
3.4.5
reference heat gain due to person
maximum hourly total (sensitive and latent) heat gain due to person inside the room or zone (3.1.2) in
watt per unit floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), heat gain due to person at the time can be calculated.
3.4.6
reference sensible heat gain due to person
maximum hourly sensible heat gain due to person inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), sensible heat gain due to person at the time can be
calculated.
3.4.7
reference latent heat gain due to person
maximum hourly latent heat gain due to person inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), latent heat gain due to person at the time can be
calculated.
6 © ISO 2016 – All rights reserved

---------------------- Page: 14 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
3.4.8
reference heat gain due to lighting
maximum hourly sensible heat gain due to lighting inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios, heat gain due to lighting at the time can be calculated.
3.4.9
reference heat gain due to appliances
maximum hourly total (sensible and latent) heat gain due to appliances inside the room or zone (3.1.2)
in watt per unit floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), heat gain due to appliances at the time can be
calculated.
3.4.10
reference sensible heat gain due to appliances
maximum hourly sensible heat gain due to appliances inside the room or zone (3.1.2) in watt per unit
floor area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), sensible heat gain due to appliances at the time can be
calculated.
3.4.11
reference latent heat gain due to appliances
maximum hourly latent heat gain due to appliances inside the room or zone (3.1.2) in watt per unit floor
area
Note 1 to entry: To be multiplied by hourly ratios (3.4.12), latent heat gain due to appliances at the time can be
calculated.
3.4.12
hourly ratio
ratio of hourly value of parameters to their reference value
Note 1 to entry: Multiplying hourly ratios by the reference value, hourly values of the parameter can be calculated.
4 Framework of the schedule and condition for building energy calculation
4.1 Indispensable schedules
The building energy calculations are characterized by the division number of the year, the calculation
period or the calculation interval. Each calculation method has its appropriate calculation interval
according to characteristics of the target physical phenomenon (for example, unsteadiness) and
minuteness of the calculation responding to changes of climatic condition, occupants’ behaviour,
behaviour of service systems and so on.
Due to the variety of calculation method, there is a variety of form of the schedule and condition of
building, zone and space usage. Nevertheless, there is a fundamental unit of form, daily schedule, which
shall be included in forms for the schedule and condition. The daily schedule corresponds to the
minimum cycle of building, zone and space usage, and also of climatic and solar condition.
Some nations adopt so called “monthly calculation” for space heating and cooling energy needs and
uses, taking monthly variation of outdoor temperature and solar irradiance into consideration. One
daily schedule for business day and the number of the business days is given to each month for each
type of building, zone and space. Monthly means of outdoor air condition (for example, temperature)
© ISO 2016 – All rights reserved 7

---------------------- Page: 15 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
and solar irradiance for different orientations and inclinations are given for the calculation. The
expression of the daily schedule varies from detailed expression with hourly values to simplified
expression such as daily mean values and the like. Additional schedule for closing day can be given in a
simplified way such as only with daily mean values.
Similarly, in so called “seasonal calculation”, one daily schedule for business day and the number of the
business days for each season are given to each season for each type of building, zone and space, and
the calculation is done with seasonal mean values for climatic condition.
For the calculation of more steady phenomena, so called “annual calculation” can work if seasonal
change of solar condition is integrated throughout the year and condensed in specific coefficients.
Nevertheless, one daily schedule for business day and the number of annual business days are
necessary. Additional daily schedule for closing day can be given.
For the calculation of lighting, monthly or yearly calculation is mainly used, but unsteady aspects of
lighting still can be dealt with. In the calculation for lighting, when input parameters such as operating
hours with and without daylight are prescribed, daily schedule as described in the column (2) of Table 1
and annual schedule by monthly allocation of daily schedules (Table 5) or annual schedule without
division of the year (Table 7) should be explicitly given, so that the operating hours for light is well
harmonized with those for other technical systems.
Therefore, for each category of building, zone and space, necessary number of daily schedules (e.g. two
daily schedules for business day and closing day), and one of annual, seasonal, monthly and weekly
schedules shall be given in order that the daily schedules are allocated for the year.
4.2 Daily schedule
The daily schedule shall contain hourly values of condition for one day or shall contain condensed or
simplified information on conditions for the day. With some assumptions, the hourly detailed values can
be generated from condensed or simplified information and used even for detailed calculation. If
necessary, multiple daily schedules representing different daily patterns of usage should be given such
as for weekdays, weekends and holidays. The number of daily schedules depends on minuteness of the
schedule and condition, as well as on the category of building, zone and space under consideration.
The conditions described in the daily schedule are grouped into the following three categories:
a) general information on occupancy and usage of building, zone and space;
b) operation of technical building systems and requirement for their services;
c) internal heat gains.
The basic structure of daily schedule is shown in Table 1.
8 © ISO 2016 – All rights reserved

---------------------- Page: 16 ----------------------
oSIST ISO 18523-1:2020
ISO 18523-1:2016(E)
Table 1 — Framework of daily schedule for building, zone or space
(1) description by hourly (2) condensed or simplified
Parameters and their categories
values for 0 h to 24 h description
a) General Occupancy density Hourly occupancy density Times of start and end of
information on occupancy or total hours of
occupancy and occupancy, and average occupancy
usage density during usage
Simultaneous Hourly simultaneous usage Mean simultaneous usage ratio
usage ratio of a set ratio during usage
of rooms
b) Operation of Space heating Hourly status of space heating Times of start and end of operation,
technical and/or cooling and/or cooling system (in or or total hours of operation
building systems out of operation)
and requ
...