ISO 19454:2019

INTERNATIONAL ISO
STANDARD 19454
First edition
2019-08
Building environment design —
Indoor environment — Daylight
opening design for sustainability
principles in visual environment
Conception des bâtiments — Espace intérieur — Conception des prises
du jour pour les principes de durabilité dans l'environnement visuel
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Fundamentals . 4
4.1 General . 4
4.2 General principles of sustainability . 5
4.3 Project information . 5
4.4 Framework of generation and verification . 5
4.5 Framework of documentation at approval . 6
4.6 Harmonization of architectural and daylight opening design. 6
5 Design elements of daylight openings . 6
5.1 General . 6
5.2 Matrix of aspects of daylight opening design . 7
5.3 Daylight opening ratio to the wall area . 8
5.4 Daylight opening ratio to the floor area . 8
5.5 Levels of indoor daylight and the extent of sunlight . 8
5.6 Quality of views to exterior . 8
5.7 Daylight control systems in the building . 9
6 Design process of daylight openings . 9
6.1 General . 9
6.2 Stage I — Formulation of project definition . 9
6.2.1 Project definition . 9
6.2.2 Output — Document I .10
6.2.3 Evaluation I .10
6.2.4 Output — Approval of document I .10
6.2.5 Iteration .10
6.3 Stage II – Schematic design .10
6.3.1 General.10
6.3.2 Input .10
6.3.3 Output .11
6.3.4 Evaluation II .11
6.3.5 Approval of document II .11
6.4 Stage III – Detailed design .11
6.4.1 General.11
6.4.2 Input .11
6.4.3 Output – Document IIIa.12
6.4.4 Analysis .12
6.4.5 Output – Document IIIb .12
6.4.6 Evaluation III .13
6.4.7 Approval of documents IIIa and IIIb .13
6.4.8 Iteration into detail design .13
6.5 Stage IV – Final design .13
6.5.1 General.13
6.5.2 Commissioning documents .14
6.5.3 Cost estimation .14
6.5.4 Output: the final documents .14
Annex A (normative) Flow diagram of the design process .16
Annex B (informative) Basic architectural forms of the daylight opening .17
Annex C (informative) Matrix of aspects of daylight opening design .19
Annex D (informative) Matrix of output required to satisfy daylight opening design .23
Bibliography .26
iv © ISO 2019 – All rights reserved

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
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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
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.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 205, Building environment design.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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Introduction
ISO 16813 provides general principles for the design of the indoor environment for buildings. The
design process for the indoor visual environment is provided by ISO 16817 to ensure required visual
comfort, good physiological effects of light and building energy performance and sustainability.
This document provides design team members with a design process for daylight openings under the
umbrella of ISO 16813 and ISO 16817. Receiving daylight is a fundamental human need. It is essential
to ensure favourable daylight environments in buildings. Daylight opening design is an indispensable
element of building design. This document is targeted at habitable rooms in all buildings to ensure
sufficient, quality daylight.
For this document, both windows and rooflights are deemed daylight openings. The size and position of
the daylight openings affect the amount of daylight entering a room as well as the view from the daylight
opening. An appropriate sizing of the daylight opening ensures a necessary level of daylight and an
impression of spaciousness. However, large daylight openings can require more control of daylight in
terms of visual and thermal environments. Qualities of daylight admitted through the daylight opening
vary depending on the direction in which the daylight opening faces.
This document:
— provides a framework for taking into consideration various parameters and criteria in daylight
opening design;
— is intended for use by design teams (architects and engineers), building clients, contractors,
government officials and academics;
— is aimed at assisting these groups in designing daylight openings in the process of building design;
— incorporates sustainability considerations into the design of indoor visual environments.
vi © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 19454:2019(E)
Building environment design — Indoor environment —
Daylight opening design for sustainability principles in
visual environment
1 Scope
This document provides a design process for daylight openings in order to ensure the principle of
sustainability in the indoor visual environment. The design process for daylight openings includes the
consideration of:
— sunshine duration in the building interiors;
— daylight opening ratio to the wall area of a habitable room;
— daylight opening ratio to the floor area of a habitable room;
— appropriate levels of indoor daylight based on human visual needs and the extent of sunlight;
— daylight control systems in the building;
— thermal comfort, thermal gains and energy efficiency.
This document is applicable to building environment design for new buildings and the retrofit of
existing buildings.
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 8995-1, Lighting of work places — Part 1: Indoor
ISO 16817:2017, Building environment design — Indoor environment — Design process for the visual
environment
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:
— ISO Online browsing platform: available at http: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
commissioning
sequence of events that ensure the building and the technical building systems (3.16) are functioning in
accordance with the design parameters for the building lifetime
[SOURCE: ISO 16813:2006, 3.7 modified — The word “HVAC” has been replaced with “technical
building”.]
3.2
daylight
part of global solar radiation capable of causing a visual sensation
[SOURCE: CIE S 017/E:2011, 17-278]
3.3
daylight opening
area, glazed or unglazed, that is capable of admitting daylight (3.2) to an interior
Note 1 to entry: Basic architectural forms of the daylight opening are illustrated in Annex B.
[SOURCE: CIE S 017/E:2011, 17-284, modified — Note 1 to entry has been added.]
3.4
daylight opening ratio
daylight opening ratio to the floor area
daylight opening ratio to the wall area of a habitable room
ratio of the daylight opening area to the corresponding floor or wall area of a habitable room
Note 1 to entry: “Window-to-wall ratio (WWR)” is defined as “ratio of the fenestration area to the gross exterior
[2]
wall area” in ISO 16818:2008, 3.249 .
3.5
design team
group of people who are responsible for building design
Note 1 to entry: The design team can consist of an architect, an interior designer, a lighting designer, a landscape
designer, engineers in electrical engineering, illuminating engineering, HVAC systems, structural engineering
and construction management and other specialists.
3.6
direct solar radiation
part of extra-terrestrial solar radiation which, as a collimated beam, reaches the earth's surface after
selective attenuation by the atmosphere
−2
Note 1 to entry: The quantity measured is the direct solar irradiance, expressed in W·m .
[SOURCE: ISO 9846:1993, 3.6, modified — The last sentence in the original definition has been changed
to Note 1 to entry.]
3.7
habitable room
room that is continuously used for living, working, meeting, amusement and other purposes similar
thereto
[SOURCE: ISO 18523-2:2018, 3.1.7]
3.8
possible sunshine duration
possible sunshine duration at a particular location
sum of the time intervals within a given time period during which the sun is above the real horizon
Note 1 to entry: The possible sunshine duration can be obscured by mountains, buildings, trees, etc.
[SOURCE: CIE S 017/E:2011, 17-972, modified — The last sentence in the original definition has been
changed to Note 1 to entry.]
3.9
relative sunshine duration
ratio of sunshine duration (3.14) to possible sunshine duration (3.8) within the same time period
Note 1 to entry: The unit is 1.
2 © ISO 2019 – All rights reserved

[SOURCE: CIE S 017/E:2011, 17-1086]
3.10
rooflight
skylight, US
daylight opening (3.3) in a flat roof or low-pitched roof, intended primarily for lighting and consisting of
a frame and glazing
Note 1 to entry: In the US, there is a homograph for the term “skylight”. See 3.11.
[SOURCE: ISO 6707-1:2017, 3.3.3.13, modified — The words "construction for closing an" have been
deleted and “daylight” has been added.]
3.11
roof window
skylight, US
daylight opening (3.3) in the plane of a pitched roof, which admits light and which can provide ventilation
Note 1 to entry: In the US, there is a homograph for the term “skylight”. See 3.10.
[SOURCE: ISO 6707-1:2017, 3.3.3.14, modified — The words "construction for closing an" have been
deleted and “daylight” has been added.]
3.12
spaciousness
spatial largeness and extensiveness, especially inside a building
3.13
sunlight
part of direct solar radiation (3.6) capable of causing a visual sensation
[SOURCE: CIE S 017/E:2011, 17-1281]
3.14
sunshine duration
sum of time intervals within a given time period (hour, day, month, year) during which the irradiance from
−2
direct solar radiation (3.6) on a plane normal to the sun direction is equal to or greater than 120 W·m
[SOURCE: CIE S 017/E:2011, 17-1282]
3.15
sustainability
maintenance of ecosystem components and functions for future generations, to address economic
efficiency, social issues and environmental preservation
[SOURCE: ISO 16813:2006, 3.27]
3.16
technical building system
technical equipment for heating, cooling, ventilation, humidification, dehumidification, domestic hot
water, lighting, building automation and control and electricity production
Note 1 to entry: A technical building system can refer to one or to several building services (e.g., heating, cooling,
lighting and domestic hot water).
Note 2 to entry: A technical building system is composed of different sub-systems.
Note 3 to entry: Electricity production can include cogeneration, wind power and photovoltaic systems.
[SOURCE: ISO 52000-1:2017, 3.3.13, modified — The word “lighting” has been added in Note 1 to entry.]
3.17
visual comfort
occupant satisfaction which the indoor visual environment, described in terms of illumination level,
glare, visibility, reflection, quality view and psychological and physiological content with natural and
artificial illumination
[SOURCE: ISO 16813:2006, 3.29, modified — The words “quality view” have been added.]
3.18
window
daylight opening (3.3) on a vertical or nearly vertical area of a room envelope
[SOURCE: CIE S 017/E:2011, 17-1436]
4 Fundamentals
4.1 General
Daylight opening design is a part of designing the indoor visual environment in the process of designing
a building. It shall be appropriately included in the integrated design process provided by ISO 16817
in order to achieve the quality indoor visual environment. Daylight openings influence not only the
visual environment but also the thermal, acoustical and air environments in buildings. An integrated
multidisciplinary approach by a design team has important implications for daylight opening design.
The integrated design process ensures an efficient and effective design to obtain the specified quality
and performance level of safety, health, comfort and energy efficiency in buildings. ISO 16813 provides
a flow diagram of the design process. The design process for daylight openings shall follow this process,
as shown in Annex A. Daylight opening design shall be started at the initial stage of building design.
Daylight can provide large quantities of light indoors, with great spectral quality and variability
changing though the day and seasons. Windows provide a view and information about the outside and
contribute to the psychological wellbeing of occupants. Windows, rooflights and roof windows can also
provide exposure to sunlight indoors, which is important in e.g. dwellings, hospitals and nurseries.
However, windows can give rise to glare. Careful consideration should be given to window screens,
glazing materials and the reflectance of interior surfaces.
Exposure to sunlight is an important criterion because sufficient exposure to sunlight contributes
to human health and a sense of wellbeing; but some rooms have to avoid receiving sunlight for
their functionality. Besides, sunlight often causes glare directly or indirectly. It is of consequence in
workplaces. Adequate sunlight controls should be provided to avoid visual discomfort as well as an
overheating problem.
[3,4]
A certain level of the sunshine duration should be ensured in a habitable room for wellbeing .
Regional characteristics of direct solar radiation are expressed by the possible sunshine duration and
the relative sunshine duration. In high-latitude regions, it is difficult to receive sufficient direct solar
radiation in winter. In equatorial regions, south- and north-facing façades receive less direct solar
radiation, whereas east- and west-facing façades receive more during a day. Direct solar radiation
incident on the building exterior should be considered at the early stages of design. Incorrect decisions
about the geometrical shape of the building can prevent the admission of sunlight into rooms.
The performance of daylight openings is influenced by site characteristics. Large obstructions can
have an impact both on the amount of light reaching daylight openings and on the daylight distribution
within rooms, and subsequently on the indoor visual environment. The building shall be planned so that
building interiors will be illuminated by daylight in accordance with need for satisfactory performance
of visual tasks. One or more habitable rooms should receive sunlight except where unavoidable
circumstances are produced by the surrounding conditions of the site.
4 © ISO 2019 – All rights reserved

4.2 General principles of sustainability
ISO 16817 provides nine general principles of sustainability (NGPS) in designing the indoor visual
[5]
environment following ISO 15392 . Daylight opening design shall follow these principles. The NGPS are:
— continual improvement;
— equity;
— global thinking;
— holistic approach;
— involvement of interested parties;
— long-term consideration;
— precaution and risk management;
— responsibility;
— transparency.
The NGPS are based on the concept of sustainable development that meets the needs of the present
without compromising the ability of future generations to meet their own needs from economic,
[5]
environmental and social aspects . Sustainable development of buildings brings about the required
performance and functionality with minimum adverse environmental impact. It includes consideration
of all components of the building from a single product to technical building systems for the life cycle.
The continual improvement is recurring activity to enhance all aspects of sustainability. The equity
encompasses balanced and objective consideration of intergenerational, interregional and intra-
societal ethics. The global thinking encompasses consideration of regional and global consequences of
acting locally. The holistic approach encompasses inclusion of all aspects of sustainability over the life
cycle of the building. The involvement of interested parties encompasses consideration of contributions
and requirements of interested parties relative to their respective areas of responsibility and the
timing of their involvement. The long-term consideration encompasses short-, medium- and long-term
implications in decision-making. The precaution and risk management encompass avoidance of risks
and unfavourable impacts. The responsibility encompasses the moral responsibility for actions. The
transparency encompasses presentation of the information in a manner that is open, comprehensive,
understandable, and traceable with verifiable credibility.
The daylight opening and accompanying daylight control systems are important components of the
building. ISO 16817 specifies that building designers should define goals based on the requirements,
constraints and actual conditions, considering the owning and operating costs during the design stage.
The design team should appropriately define goals for the daylight opening design.
4.3 Project information
ISO 16817 specifies that the available project information which influences the development of design
concepts, together with constraints and all requirements, shall be documented at the beginning of a
project. The project information also influences design concepts of daylight openings. A description of
the intended use (and related requirements) of the building and end users’ needs shall be included. The
information on the local climate is fundamental to designing daylight openings as well as the building.
When assumptions are made in lieu of necessary information related to the standards or regulations
for the daylight opening design, these assumptions shall be documented.
4.4 Framework of generation and verification
Daylight opening design is a part of architectural design and building system design, which are goal-
driven activities. In designing the building environment, the routes necessary to achieve the end result
are not straightforward and shall be flexible. In some instances, the assumptions are made under
uncertain conditions. The design choices shall be focused on the limitation of adverse environmental
impacts. Hence, the design process involves the iteration of generation, verification and validation of
the design decisions. Daylight opening design shall be included in the iterative design at each stage of
the design process.
When a decision is to be made, the design team shall make a systematic review of the potential effects
of that decision on thermal, acoustic and visual comfort. The generation process is a sub-process where
a design solution is found by synthesizing different requirements and constraints, while the verification
process is another sub-process in which the design solution is rated against different design criteria.
The expected performance of the daylight openings shall be achieved during the above processes. When
the targets are not met, the design team shall determine the acceptability and act accordingly.
4.5 Framework of documentation at approval
The evaluation and approval processes shall be documented for the daylight opening design as well as
the other factors in the project. The documentation process shall explicitly state what is to be provided
by the project. The evaluation and approval process shall demonstrate that the stated goals can be
achieved. Every document provided shall describe the characteristics planned and verify whether they
are actually achieved. Transparent decision-making and communication processes shall be established.
Essential plans for maintenance of the daylight openings and the control systems shall be documented
according to the expected service life of the building. Approval should be obtained at each design stage.
The documents issued during the design process for daylight openings shall cover the following
questions:
— Is the daylight opening design in compliance with regulation and standard requirements?
— Is the daylight opening design for the quality visual environment feasible?
— Is the specified daylight opening design expected to satisfy the environmental, economic and social
constraints and requirements?
— Is the daylight opening design capable of providing the performance required?
4.6 Harmonization of architectural and daylight opening design
Architectural design and the building system design influence the design and construction of the indoor
visual environment. The daylight opening design is directly connected with the architectural design.
The general principles of building environment design for visual comfort should support creative
architectural design. The principles do not pre-define the order or precedence of individual tasks in
both the architectural and daylight opening designs.
5 Design elements of daylight openings
5.1 General
In order to design a high-performance and high-quality visual environment, an integrated architectural
approach is recommended. The daylight opening design shall be a part of this integrated approach that
addresses the critical interactions among the building envelope (that admits heat and light), building
interior and all light sources such as daylight (skylight and/or sunlight) and electric light. This approach
also shares appropriate decisions across the owner and the design team throughout the design process.
ISO 16817 defines the design process to ensure the quality of the indoor visual environment. In
designing daylight openings, the following elements should be taken into consideration at each stage of
the design process:
— daylight opening ratio to the wall area of a habitable room;
— daylight opening ratio to the floor area of a habitable room;
6 © ISO 2019 – All rights reserved

— levels of indoor daylight based on human visual needs and the extent of sunlight;
— quality of views to exterior;
— control of glare caused by daylight;
— daylight control systems in the building.
Designing daylight openings does not consider daylight alone. Other visual, thermal, acoustic, privacy
and security issues need to be addressed. During the design process, the glare control and thermal
comfort especially should be considered along with the above elements. Achieving a balance between
luminous and thermal environments is of primary importance in sustainable building design. Thermally,
glazed openings are a sensitive point in the building envelope. They admit more heat in summer and
lose more heat in winter than the solid part. Sunlight penetration permits solar heat gain. It can cause
preferable heating effects or unwanted overheated spots even in winter depending on circumstances.
Designing daylight openings requires local and vernacular considerations. Local climates and related
outdoor daylight conditions are fundamental existing conditions.
In very-high-latitude regions with very low solar altitudes in winter, the design issues related to
sunlight should be covered in the relevant national standards. The design team shall carefully consider
the glare problem from the sun shining close to the horizontal. The sunlight from the low altitudes
penetrates deep inside the room. It requires blinds or curtains on south-facing windows in the Northern
Hemisphere or for north-facing windows in the Southern Hemisphere to be closed all day long. However,
the solar heat gain is inevitably reduced.
As to the heating effect, in cold winters, people near windows facing south in the Northern Hemisphere
or facing north in the Southern Hemisphere could feel the excessive heat from the sunlight depending
on situations, whereas those near windows facing the opposite direction feel cold in the same room.
It would be an operational issue for sunlight control or heating. Overheating is likely to occur in the
afternoon depending on the window orientation in winter even in middle-latitude regions. Perimeter
zones with glazed curtain walls are sometimes planned as a circulation or meeting space in large open
offices.
Another indirect consequence of the difficult heating/cooling design constraints is the metallic layers
used to create a selective barrier to IR-transmission through the window glazing. However, special
metallic films of Low-E double glazing, having a low surface resistance, are liable to reflect radio waves
including WiFi signals and obstruct cellular phones and wireless network communication. Attention
is required when this kind of glazing is used together with exterior and/or insulating materials that
transmit less radio waves. The design team should keep this in mind in the use of the IR-selective
glazing.
Glazing materials affect the indoor environment. They are available in a wide range of thickness, in
clear or tinted form, in single or multiple glazed configurations. The most important parameters for the
performance of glass types are visible transmittance, thermal transmittance, solar heat gain coefficient
and emissivity. In general, the glazing specification required is high visible transmittance and low
thermal transmittance. The solar heat gain increases cooling loads but reduces heating loads. Light
reflectance to the outside should be evaluated when considering the aesthetics of the building and the
risk of glare reflected to the surrounding space and to the other buildings. Concave glass façades shall
be carefully designed, as the reflected sunlight would be focused somewhere and cause an overheating
problem.
5.2 Matrix of aspects of daylight opening design
The design of daylight openings has a direct impact on the sustainability of a building. Since their role
is more than just lighting in the building, the sustainability requirements shall be addressed from
various aspects of daylight opening design at each stage of building design. Table C.1 in Annex C shows
links between the aspects of daylight opening design and sustainability requirements enumerated in
ISO 16817. Table D.1 in Annex D shows output required to satisfy daylight opening design.
5.3 Daylight opening ratio to the wall area
The daylight opening ratio to the wall area should be determined in the project information. It is
related to the visual comfort, thermal comfort, acoustics comfort, air quality, energy performance
and sustainability of the building. The daylight and thermal conditions are often in conflict with one
another. However, the minimum daylight opening ratio should be secured for the health management of
the building environment. It can be subject to national or regional regulations.
5.4 Daylight opening ratio to the floor area
The daylight opening ratio to the floor area should be determined in the project information. It is
related to the visual comfort, thermal comfort, acoustics comfort, air quality, energy performance
and sustainability of the building. The daylight and thermal conditions are often in conflict with one
another. However, the minimum daylight opening ratio should be secured for the health management of
the building environment. It can be subject to national or regional regulations.
It should be noted that the minimum daylight opening ratio to the floor area alone is not enough to get
an acceptable indoor visual environment, as the minimum daylight opening ratio means that a small
room should have only a small daylight opening. The quality of views to exterior is indispensable even
for the acceptable indoor visual environment.
5.5 Levels of indoor daylight and the extent of sunlight
The amount of outdoor daylight varies throughout the day depending on sky conditions, and the indoor
daylight availability varies accordingly. The amount of daylight in interiors first depends on the position
and size of the daylight openings, obstructions, and skylight and sunlight conditions. The level of indoor
daylight shall follow the illumination levels at the task area and its surroundings in indoor workplaces
specified in ISO 8995-1.
The extent of sunlight into the habitable rooms should be determined in the project information.
Sunlight is undesirable from the viewpoint of glare, excessive luminance contrast and overheating.
However, it can create pleasing patterns of light and shadows on surfaces in interiors and make the
space vivid and cheerful. Exposure to sunlight in the morning is essential to maintain good circadian
rhythms.
The extent of sunlight in a room depends on that received by the façade. Site layout is an important
factor affecting sunlight onto façades. In an urban environment, the building is often designed to
completely occupy the site. If the building is in a densely-built urban area, the amount of sunlight can be
limited due to other buildings blocking the sunlight.
It is the duration of sunlight in an interior, rather than its intensity or the size of the sunny patch,
[3]
which correlates best to the occupants' satisfaction . Actual sunshine duration can be expected by the
relative sunshine duration. The possible sunshine duration at equinox (vernal or autumnal) should be
included in the project information.
[6]
For a daylighting purpose, daylight hours are referenced as the basis of daylight availability . Daylight
hours are the total number of hours between sunrise and sunset.
5.6 Quality of views to exterior
The views to exterior are defined as the views out of windows and/or rooflights. They should be
considered in the project information. It is essential to get openness and quality views to ensure
occupants' visual comfort and connection to the exterior through daylight openings. However, some
spaces need to avoid visual transparency between the inside and outside due to their use. In that case,
looking in a room from the outside is often avoided by some sort of interrupting means.
A view to the exterior provides not only an outdoor scene but also information on the outside, for
example, the weather and time. It provides a key to finding a way inside the building. Ideally daylight
openings provide a sky view and a view of the surrounding scenery. However, the quality of a view
8 © ISO 2019 – All rights reserved

is determined by the site conditions. The neighbouring outdoor environment shall be analysed at the
stage of project definition. Views to the exterior are influenced by the climate. In regions with snowfall,
snow covering the windows and rooflights reduces the view to the exterior. Even a limited view to the
exterior can be valuable under these circumstances. If an external view cannot be provided, an internal
[3]
view, for example, into an atrium can substitute for the external view to some extent .
5.7 Daylight control systems in the building
The larger the daylight opening is, the more important glazing selection and shading effectiveness are
to control glare and heat gain by users. The requirements for the daylight control systems should be
determined in the project information.
In high-latitude regions, the shading control shall be easy to adjust on a daily basis, or have automatic
adjustment, so that it provides both shading sunlight from low altitudes and a view to the exterior. The
shading needs to be adjusted according to the sun movement during the day. Alternatively, for example,
open-plan offices need to have multiple shading elements so that both sun shading and a line of sight
can be provided simultaneously. Ideally, the shading would be individual for every worker.
6 Design process of daylight openings
6.1 General
The design team is responsible for addressing human and technical issues on the project. Designing
daylight openings involves balancing benefits and disadvantages in the indoor environment and
energy performance. One is the need to access sufficient skylight and sunlight as well as good views
through the daylight openings, and the other is the need to control its adverse or unwanted effects.
The design team need to work together to achieve this balance. The daylight opening design dominates
the building design including the architectural style, structure and materials. Though the structure
of the design team depends on the scale of projects, an integrated multidisciplinary approach shall be
adopted throughout the design process by:
— identifying the necessary professional skills needed;
— sharing information on their tasks and issues;
— facilitating integrated working.
6.2 Stage I — Formulation of project definition
6.2.1 Project definition
The project definition process is defined in ISO 16817. It is the basis to make decisions on the daylight
opening design. The design team shall consider the following aspects in the project definition:
— description of the intended use (and related requirements) of the construction works and
end-users needs;
— provision of safe and resistant construction works during exceptional events;
— provision of accessibility for all;
— functional flexibility;
— security;
— contribution to social equity and improvement in the social climate;
— neighbouring outdoor environment;
— number and type of spaces (serviceability);
— constraints (see ISO 16817:2017, Tables 1, 2 and 3);
— respect of human value
...