ISO 11863:2011

INTERNATIONAL ISO
STANDARD 11863
First edition
2011-07-01
Buildings and building-related facilities —
Functional and user requirements and
performance — Tools for assessment and
comparison
Bâtiments et biens immobiliers associés — Exigences fonctionnelles,
exigences de l'utilisateur et performances — Outils pour l'évaluation et
la comparaison
Reference number
©
ISO 2011
©  ISO 2011
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ii © ISO 2011 – All rights reserved

Contents Page
Foreword .iv
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 How to determine levels of functional performance requirements and levels of
serviceability.5
4.1 Requirements for functional performance.5
4.2 Serviceability .6
4.3 Number of statements and of levels in a scale .6
4.4 Calibration and normalization of scales .7
4.5 Complex topics with multiple functions .7
4.6 Relative importance of requirements .7
4.7 Threshold or critical level.7
4.8 Main and variant requirement profiles .8
4.9 Generic profiles of demand.8
4.10 Calibration of scales .9
4.11 Gap analysis — Comparing demand and supply.9
4.12 Applicability in different cultures .9
4.13 Consistency and replicability of responses .9
4.14 Application during the whole life of a facility.10
4.15 Inclusion in the building information mode (BIM) .10
Annex A (informative) Concepts of functionality and serviceability .11
Annex B (informative) Principle of calibration for scales .13
Annex C (informative) Example of scales.14
Annex D (informative) Comparison and matching of profiles.17
Annex E (informative) Terms used for functionality and serviceability .21
Bibliography.23

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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 11863 was prepared by Technical Committee ISO/TC 59, Buildings and civil engineering works,
Subcommittee SC 3, Functional/user requirements and performance in building construction.

iv © ISO 2011 – All rights reserved

INTERNATIONAL STANDARD ISO 11863:2011(E)

Buildings and building-related facilities — Functional and user
requirements and performance — Tools for assessment and
comparison
1 Scope
This International Standard specifies how to determine functional performance requirements (demand) for
buildings and building-related facilities, and how to check the capability of buildings and facilities to meet
identified requirements (supply). It specifies how to determine the relative importance of each requirement,
establish thresholds for capability, and evaluate the significance of differences between what is required and
actual capabilities.
This International Standard is applicable to any size or scope of assets of buildings and building-related
facilities, e.g. to a portfolio of assets at a single site or multiple sites, to assets of a single small building, and
to any constituent system, sub-system, component or element thereof. It is applicable to a range of roles, from
owners and managers to occupants, tenants, or other users or stakeholders. It is applicable to any asset type
within the field of buildings and civil engineering works, including certain public works, equipment and materiel.
It is particularly useful for entities having control or occupancy of a portfolio of such assets.
2 Normative references
The following referenced documents are indispensable for the application 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 6707-1, Building and civil engineering — Vocabulary — Part 1: General terms
ISO 15686-10, Buildings and constructed assets — Service life planning — Part 10: When to assess
functional performance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6707-1 and the following apply.
3.1
aspect
〈functionality or serviceability〉 part or set of parts of the functionality (3.15) or serviceability (3.28) of an
asset (3.2), building or building-related facility (3.10)
NOTE An aspect usually encompasses multiple topics (3.33) of functionality or serviceability.
3.2
asset
〈building or building-related facility〉 whole building or structure or unit of construction works, or a system or
component or part thereof
3.3
behaviour in service
manner in which an asset (building or building related facility) (3.2) actually functions in its intended place and
use
3.4
calibrate
set the proper intervals between marks or levels (3.17) (3.18) (3.19) of a scale (3.26) (as a measuring
instrument)
3.5
calibration
act of marking the scale (3.26) of a measuring instrument used to determine the proper separation between
marks or levels (3.17) (3.18) (3.19)
3.6
capability
measure of ability to perform and support a function (3.12)
3.7
critical level
〈of functionality〉 level (3.17) (3.18) (3.19) at which resources necessary for work or other functions (3.12) are
essential or critical
3.8
demand
〈of a facility〉 requirement for functionality (3.15)
3.9
demand scale
scale (3.26) for use in determining the level of functionality (3.17) of a facility (3.10) on one topic (3.33) of
functional performance (3.13)
3.10
facility
physical setting used to serve a specific purpose
NOTE 1 A facility can be part of a building, or a whole building, or more than one building, and can include related
constructions (such as roads and walkways), which, taken as a whole, serve a specific function.
NOTE 2 The term encompasses both the physical object(s) and its (their) use.
3.11
feature
element or attribute of a facility (3.10) which indicates an aspect of its serviceability (3.28)
3.12
function
purpose or activity of users (3.34) and other stakeholders (3.29) for which an asset (3.2) or a facility (3.10)
is designed, used, or required to be used
3.13
functional performance
〈of a facility〉 performance (3.20) of a facility (3.10) to support required function(s) (3.12) under specified
use conditions
NOTE See also performance 〈of a facility〉 (3.20).
2 © ISO 2011 – All rights reserved

3.14
functional performance requirement
type and level of functional performance (3.13) which is required by stakeholders of a facility (3.10),
building or other constructed asset (3.2), or of an assembly, component or product thereof, or of a movable
asset, for a specific activity or function (3.12)
3.15
functionality
suitability or usefulness for a specific purpose or activity
3.16
gap
difference between the level of functionality (3.17) (or other attribute) which is required and the level of
serviceability (3.19) (capability) which is or will be provided
3.17
level of functionality
number indicating the relative functionality (3.15) for a group of users (3.34) or other stakeholders (3.29) for
one topic (3.33) on a predetermined demand scale (3.9) from the level of the least functionality (3.15) to the
level of the most functionality (3.15)
NOTE Level of functionality can be the consequence of several distinct functions (3.12) required to act in
combination.
EXAMPLE Scale of integers from 0 to 9.
3.18
level of performance
number indicating the relative performance (3.20) required or provided for one topic on a predetermined
scale (3.26) ranging from the level of the least performance (3.20) to the level of the most
performance (3.20)
NOTE Level of performance can be the consequence of several distinct performances [behaviours in service
(3.3)], of which one can be functional performance (3.13), which act in combination.
EXAMPLE Scale of integers from 0 to 9.
3.19
level of serviceability
number indicating the relative capability of a facility (3.10) for a group of users (3.34) or other stakeholders
(3.29) for one topic (3.33) on a predetermined supply scale (3.31) from the level of the least serviceability
(3.28) to the most serviceability (3.28)
NOTE Level of serviceability can be the consequence of several physical features (3.11) acting in combination.
EXAMPLE Scale of integers from 0 to 9.
3.20
performance
〈of a facility〉 behaviour in service (3.3) of a facility (3.10) for a specified use
NOTE The scope of this performance is of the facility (3.10) as a system, including its subsystems, components
and materials, and their interactions, such as those of an acoustical, hydro-thermal, or economic nature, and the relative
importance (3.25) of each performance requirement (3.21).
3.21
performance requirement
〈of a facility〉 performance (3.20) demanded or expected of a facility (3.10) for a specified use
NOTE Adapted from ISO 6707-1:2004, definition 9.1.16.
3.22
profile
〈of a facility〉 list of the levels of functionality (3.17) required by stakeholders (3.29) for a facility (3.10), or
of the levels of serviceability (3.19) provided by a facility, with respect to various topics (3.33)
3.23
rater
individual who conducts the rating (3.24) of a facility (3.10), or of the design of a facility, to determine its
profile (3.22) of serviceability (3.28)
3.24
rating
process of determining the serviceability (3.28) of a constructed asset (3.2), or of an asset which has been
designed but not yet built
3.25
relative importance
importance of any one topic (3.33) of functionality (3.15) for the operations or mission of the users (3.34)
3.26
scale
single set of statements, in which intervals between statements, from the most to the least, are calibrated
according to scalar rules
NOTE When people are asked to select one of the statements in a scale as most closely describing the level of
functionality (3.17) required, or as best describing the physical features present in a facility, the scale in effect functions
as a multiple choice questionnaire.
3.27
service life
period of time after installation during which a facility (3.10) or its component parts meet(s) or exceed(s) the
performance requirements (3.21)
NOTE Adapted from ISO 6707
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