ISO/DIS 15686-3.2:2025(en)

ISO/TC 59/SC 14

Secretariat: BSI

Date: 2025-09-03

Buildings and civil engineering works— Service life planning — Part 3: Methods, data and communication

Élément introductif — Élément central — Partie 4: Titre de la partie

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Contents Page

Foreword 6

Introduction 7

Part 4: Methods, data and communication 9

1 Scope 9

2 Normative references 9

3 Terms and definitions 9

4 Overview (informative) 11

4.1 Process map 11

4.2 Methods, data and communication 12

5 Common requirements 13

5.1 Objectives 14

5.2 Information 14

5.2.1 Contextual information 14

5.2.2 Input information 14

5.2.3 Data quality 14

5.3 Method 15

5.3.1 Units 15

5.3.2 Grades 15

5.4 Outcomes 15

5.4.1 Output information 15

5.4.2 Presentation 15

6 Product and material identification 16

6.1 Objectives 16

6.2 Information 16

6.2.1 Contextual information 16

6.2.2 Input information 17

6.3 Method 17

6.4 Outcomes 18

6.4.1 Output information 18

6.4.2 Presentation 18

7 Testing and provision of service life metrics 18

7.1 Objectives 18

7.2 Information 19

7.2.1 Contextual information 19

7.2.2 Input information 19

7.3 Method 20

7.3.1 Service-life data from performance in use 20

7.3.2 Service-life data from testing 20

7.4 Outcomes 21

7.4.1 Output information 21

7.4.2 Presentation 21

8 Product estimated service life 22

8.1 Objectives 22

8.2 Information 23

8.2.1 Contextual information 23

8.2.2 Input information 23

8.3 Method 24

8.3.2 Service life by estimation 25

8.3.3 Facility service life 27

8.3.4 Service life data from practical experience 27

8.3.5 Service life for innovative components 27

8.4 Outcomes 28

8.4.1 Output information 28

8.4.2 Presentation 28

9 Appraisal of components in use and their residual service life 28

9.1 Objectives 28

9.2 Information 28

9.2.1 Contextual information 28

9.2.2 Input information 29

9.3 Method 29

9.3.1 Assessing residual service life 29

9.4 Outcomes 29

9.4.1 Output information 29

9.4.2 Presentation 29

10 Uncertainty 29

10.1 Uncertainty and reliability 29

10.1 Representing uncertainty 30

10.1.1 Certain data 30

10.1.2 Simple uncertainty 30

10.1.3 Detailed uncertainty 31

Annex A : Templates and examples 33

A.1 Introduction to templates 33

A.2 References to other sources for templates 33

A.3 Terms used in templates 33

A.4 Overview 33

A.5 Template and example for general considerations 33

A.6 Template and example for product/material/assembly identification, characteristics and quantities (clause 6) 34

A.6 A.7 Template and example for product service life testing (clause 7) 34

A.8 Template and example for design assessment (clause 8) 39

A.9 Template and example for in-use assessment of residual service life (clause 9) 39

A.7 A.10 Sub-Template and example for uncertainty (clause 10) 40

Annex B : Data definitions 41

B.1 B.1 Introduction to data definitions 41

B.2 B.2 References to other sources for data definitions 41

B.3 B.3 Terms used in data definitions 41

B.4 B.4 Overview (clause 4) 41

B.5 B.5 Data definitions for common attributes (clause 5) 41

B.6 B.6 Data definitions for product/material/assembly characteristics and quantities (clause 6) 42

B.7 B.7 Data definitions for product service life testing (clause 7) 42

B.8 B.8 Data definitions for design assessment (clause 8) 43

B.9 B.9 Data definitions for in-use assessment of residual service life (clause 9) 44

B.10 B.10 Data definitions for uncertainty (clause 10) 46

Bibliography 47

Foreword

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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 document 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).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 59, Buildings and civil engineering works, Subcommittee SC 14, Service life planning.

This edition, together with ISO 15686-1:— and ISO 15686-2:—, cancels and replaces ISO 15686-1:2011, ISO 15686-2:2012, ISO 15686-3:2002, ISO 15686-4:2014, ISO 15686-8:2008, ISO/TS 15686-9:2008 and ISO 15686-10:2010, which have been technically revised.

A list of all parts in the ISO 15686 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

The ISO 15686 series on constructed assets, including service life planning, is an essential contribution to the development of a policy for service life planning of constructed assets.

This document specifies methods, data structures and communication activities to be implemented as part of service life planning of constructed assets and their components. Supporting guidance is given in the form of templates and data definitions. The main audience is product, facility and information managers.

For this to occur it is considered that an information system is needed. An information management system suitable for carrying out the service life planning process should, for example, be able to:

— capture enough information and support the methods needed to calculate the effect of the environment and microclimate on the materials and components used,

— define maintenance schedules for different qualities of materials installed under different environmental conditions.

— apply life cycle costing methodologies using the captured data to calculate the benefits of using either high performance materials with little maintenance or lower performance materials with better maintenance procedures. Procedures need to be able to take ease of replacement and demolition into account,

— incorporate new knowledge and predictive methods for material performance and maintenance without affecting methods and data structures that enable calculations based on current knowledge,

— support interoperability between software applications, and

— be used by designers, constructors, owners, operators and demolishers throughout the built asset life cycle.

In practice, this means applying the technology that is generally being termed information management and in some cases building information modelling (BIM) systems. BIM and the use of software applications that enable it is becoming a normal way of working within the built environment sector It offers significant benefits including the ability to work with components and assemblies as objects that encapsulate both shape (in the form of geometric information) and other information about performance, delivery, operation and more. Performance can include information about durability and sustainability metrics. This offers powerful capabilities for dealing with these key areas of interest at every level from individual component to constructed facility.

This document is particularly concerned with the provision of information for service life planning. It proposes structures for the capture and exchange of service life planning information based on the Industry Foundation Classes (IFC) standard for information exchange and sharing.

Clause 4 provides the service life planning context within which it is prepared. Clauses 5 to 10 each covers a stage of the lifecycle of service life information .c, starting with its measurement and publication, followed by its adjustment in the context of a particular facility and finally its use in whole-life calculations. Annexes A and B summarize the standard properties and provide worked examples of how the data might be used in manual or automated calculations.

Buildings and constructed assets — Service life planning — Part 3: Methods, data and communication

This document provides requirements and guidance on the methods, data, and communication of service life planning of constructed assets and their components as well as the required supporting data.

This document specifies the structure and representation of service life data. It is focused on key exchange requirements underlying four common transactions.

This document can be used:

a) to achieve and maintain a common understanding within the national and project contexts;

b) to establish the desired outcomes and to define appropriate quality;

c) to identify appropriate management effort and tools;

d) to identify necessary effort and resourcing.

Service life planning involves the application of data about elements within constructed assets to enable their design, predicted or estimated service life to be determined and communicated.

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 15686‑1, Buildings and constructed assets — Service life planning — Part 1: Concepts and principles

ISO 15686‑2, Buildings and constructed assets — Service life planning — Part 2: Process considerations

ISO 15686‑7, Buildings and constructed assets — Service life planning — Part 7: Performance evaluation for feedback of service life data from practice

ISO 16739‑1, Industry Foundation Classes (IFC) for data sharing in the construction and facility management industries — Part 1: Data schema

ISO 80000, — Quantities and units

For the purposes of this document, the following terms and definitions apply.

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

— ISO Online browsing platform: available at https://www.iso.org/obp

— IEC Electropedia: available at https://www.electropedia.org/

3.1

object

unique occurrence of an item belonging to a class such that the attributes and constraints are defined by the class, having its own identity, behaviour and values for its attributes (state)

3.2

property set

grouping of properties that belong together based on some principle.

EXAMPLE A principle can be life cycle stage or purpose

3.3

quantity set

grouping of characteristic measure properties

The process map (see Table 1) shows the sequence of processes (ISO 15686-2) and information exchanges (this document) in context.

In summary, this part covers four methods for working with service life data.

— Clause 6: covers the specification/selection of product: product and testing are brought together to obtain the service life characteristics;

— Clause 7: covers the testing regimen and the key service life metrics: the characteristics are brought into a specific context to obtain a predicted service life;

— Clause 8: covers the facility context and the predicted/estimated service life: the predicted or measured service life is used with cost or environmental impact rates to obtain a life cycle cost or assessment;

— Clause 9: covers the impacts (to date and predicted) for stages in the life cycle value: the context factors are revised to reflect in-use surveys.

To support these:

— Clause 5: defines the common requirements for applying this document

— Clause 10 covers the consideration and representation of uncertainty

— Clauses A.6 to A.10 offers templates

— Clauses B.6 to B.10 offer formal data definitions

Table 1 — Service life processes and information requirements

The determination of service life is undertaken at various times during the product development and during design, construction and operation of a facility. During the early design stages when product information is aggregated a level such as the whole facility or as specifications of whole systems; it is only the design life of a product that can be determined. At the earliest design stages when only product occurrences are defined, the design life is estimated at the occurrence level. At later design stages, when individual products are located and these products are designated by type, the design life can be indicated for all occurrences at the type level. Similarly, when individual products are identified, it becomes possible to determine a reference service life when a manufacturer/supplier can be identified. As with the design life, the reference service life can be allocated to the product type level.

At later design stages and during construction, when the configuration and location of products has been fully established, it becomes possible to analyse the service life of products according to in-use conditions. These conditions can vary the reference service life depending on factors such as exposure to weather, aggressiveness of the local environment and other degrading (or upgrading) factors. The result of applying in-use conditions is to define an estimated service life which is simply the length of time of a product occurrence life cycle.

Finally, the condition of a product occurrence can be checked from time to time during the operational stage. From the condition of the product, a residual service life can be assessed. If degradation is more than has been expected, the residual service life is reduced.

The overall data requirements for the process are summarized in Figure 1.

Figure 1 — The ‘service life planning view’

The application of any of the methods detailed in Clauses 6 to 10 shall be based on clear objectives including the desired outcome and the acceptable levels of confidence.

Context information shall be provided, including:

a) identification of the product or facility;

b) identification of the responsible author;

c) identification of the commissioning client;

d) date and version of the report;

e) statement that the study has been conducted in accordance with all the requirements of this document.

The information inputs shall be clearly stated with their source and confidence.

Sources of data and any third-party assessment or test results shall be provided to enable the data user to assess the quality of the data.

The basis, including the sources and quality of the data used, shall be clearly stated in a written report.

NOTE This is essential to enabling the judgement of the quality of the service-life prediction being undertaken and to enabling risk of error to be adequately considered.

The quality of both input data/information and output data/information shall be stated in the report of any service life planning activity.

NOTE The quality of service life estimation depends in part on the quality of the data used to generate the service life estimation. A possible problem with observations in situ is that agents (e.g. weather conditions) can be not reported, or those reported can be not typical, and can not reflect conditions comparable to those to which a component would be exposed in service. Anecdotal evidence of performance is less reliable than scientific evidence, but can be all that is available. In addition, selective reporting of data can be encountered when commercial interests are involved (e.g. a supplier might report positive, but not negative, exposure results). It is to be expected that the situation will improve when criteria are established for the scope and quality of data to be supplied by manufacturers and others for inclusion in databases, and as computer-integrated knowledge systems for service life estimation are developed.

The method applied shall be clearly stated including a reference to Clauses 6 to 10 and any deviations noted.

The report shall also provide the assumptions underlying the estimations.

Values related to the service lives shall be expressed in a period of years, whether they consist of discrete values, such as mean values and standard deviations, or full distributions. For the description of the in-use condition(s), where applicable, the International System of units (SI) shall be used. Symbols for quantities shall be chosen, wherever possible, in accordance with the ISO 80000 series.

Grades shall be expressed in phrases taken from a verbal scale unless there is a clear numeric metric for intensity available for both reference and contextual situations.

The information outputs shall be clearly stated with their confidence.

The report shall also provide a conservative estimate of the uncertainty.

Note: These records can be required for a subsequent review or audit.

The context, inputs, method and outputs shall be presented in a structured and clear format.

Results shall be communicated to the parties who can use the information so that they are aware of the actions implied. The results of the study shall be reported to all interested parties.

The findings of all analyses, data, methods, assumptions and limitations shall be presented in sufficient detail to enable assessment the quality of the information. The report shall also allow the results and interpretation to be used in a manner consistent with the goals of the study.

The report shall include measured, calculated or estimated statistical distributions (see Clauses 10 and A.10).

NOTE 1 Distributions can, for example, be expressed in terms of distribution functions, standard deviations or levels of confidence.

NOTE 2 These records can be required for a subsequent review or audit.

NOTE 3 Clauses A.6 to A.10 provide presentation templates.

NOTE 4 Clauses B.6 to B.10 provide formal information specifications.

This clause along with clause 5 provides the definition of a product typically by the manufacturer so that the information associated can be exchanged and used, particularly by testing organizations. The identification of a product is central to the effective persistence of the information.

This subclause defines the representation of the characteristic measures of a product as a quantity set. Performance characteristics specific to its specification and selection can also be added. These characteristics are relevant to deeper searching and the construction of benchmarks and comparators.

A detailed description of the product, component, material or assembly shall be provided.

Context information shall be provided, including:

a) the product, initially as an abstract library type and latterly as an instantiated occurrence;

b) the identity of the product, including its name, description and other properties that make it uniquely identified;

c) the source of the product, in terms of the originating organizations, author, and any reference documents;

d) optionally, classification and grouping of the product according to local practice which aids in the searching and the reporting of the product; one or more classifications can be associated to a product:

— name, source and edition of the classification system;

— name and description of the classification entry.

e) component description, comprising:

— main or other identification marks of the components;

— designation of the components in accordance with recommendations or prescriptions expressed in official standards or regulations;

— description of the components;

f) an owner history with a definition of the authoring person and organization; these can have full address and contact details:

— authoring person and organization with role;

— application or method used;

g) additional information relating to constituent components:

The component to be evaluated shall be characterized thoroughly in terms of structure, physical properties and chemical composition.

Methods for determining the quantities and characteristics are out of scope.

NOTE ISO 12006-3 specifies dictionaries suitable for defining such quantities and characteristics.

General

This subclause defines the representation of the characteristic measures of a product as a quantity set. Performance characteristics specific to its specification and selection can also be added. These characteristics are relevant to deeper searching and the construction of benchmarks and comparators.

Functional measures and quantities

Information shall be provided for characteristic functional measures and quantities. If no measure is given then a unit count shall be assumed. In the case of materials and layered constructions, a unit volume or area shall be provided.

Selection and performance characteristics

Information shall be provided for characteristic selection and performance properties. The selection of these properties may be specific to the type of product, the locale and the procurement method.

Clause 7 along with clause 5 covers the testing regimen and the key service life metrics for the publication of product data, typically by testing organisations and product data publishers so as to associate service life information to a generic or specific material or assembly.

This clause adds representation of the testing regime that has evaluated a product and the key service life metrics so as to associate service life information to a generic or specific material or assembly, for use in the subsequent use cases. The authority for the metrics is documented so that the metrics can be verified by recourse to the original source.

Products shall have their several possible applications or intended uses described. intended uses and any limits on in-use conditions for which it is suitable shall be provided. Guidance shall be given on the end uses to which the service-life data provided are relevant.

Context information shall be provided, including:

— identification of the product;

— identification of the responsible author, appointer;

— date and version.

The information inputs shall be clearly stated with their source and confidence.

The reference service (in-use) conditions and degradation agents to which the component is expected to be exposed in service shall be given. Where the reference (in-use) conditions assume specific provisions for particular measures, these shall be stated. Such measures may include:

— use of a protective coating or cover;

— use of a given (minimum) thickness of material;

— recommendations on installation conditions in the works;

— recommended maintenance requirements.

Reference service life shall be stated as either a single value (e.g. a modal value) or a statistical distribution for the assessment or testing under particular conditions under the prescribed conditions.

The reference in-use conditions, as well as the reference service life, shall be stated so that users of the data can judge the possible differences between the reference in-use conditions and the likely actual in-use conditions in a particular case.

NOTE  Common sets of reference in-use conditions can be defined by producers or users of products, in order to facilitate comparison of service-life data for a number of products within the same product family.

The method applied shall be clearly stated.

NOTE Service-life data can be obtained from several sources.

Service-life data shall be based on feedback data in accordance with ISO 15686-7 or data resulting from prediction procedures in accordance with ISO 15686-2.

NOTE 1 Wherever possible, performance data that have been obtained from practical experience of actual performance under clearly documented in-use conditions should be used for service-life prediction.

Evidence of performance in use shall be documented to ensure transparency.

NOTE 2 ISO 15686-7 gives further guidance on the use of feedback data from actual performance.

Where actual performance data under clearly documented in-use conditions are not available, test data shall be used for service-life prediction. If properly documented test data are already available, they shall be used without further testing. Where further testing is required, it shall be performed in accordance with ISO 15686-2.

There are two categories of testing, direct and indirect.

a. Direct testing: the achievement of a certain level of performance in a test of a particular property shall be recognized as being direct evidence of expected service life (e.g. abrasion, fatigue, closing and impact tests).

b. Indirect (proxy) testing: the measurement of “proxy” characteristics shall be correlated to actual performance and hence service life (e.g. porosity for freeze-thaw resistance and hardness for abrasion resistance).

Tests can be long-term, short-term or a combination of both. They can be carried out using small-scale or full-scale specimens, or a combination of both.

a) Long-term tests can include:

1) field exposure;

2) exposure in experimental facilities.

b) Short-term tests can include:

1) accelerated short-term tests;

2) short-term in-use exposures.

Tests can be either:

a. natural weathering/aging tests, which either give a direct indication of service life (e.g. corrosion tests) or enable normal performance tests to be carried out after treatment, thus allowing the likely degradation under in-use conditions to be determined, or

b. accelerated weathering/aging tests, in which the normal aging process is speeded up to reduce the duration of the test. Care shall be taken to ensure that degradation mechanisms are accelerated and not significantly altered in such tests.

The methodology used to derive the reference service life shall be reported.

The data sources used and a brief explanation of the reasons for their use shall be provided.

Information shall be provided for the service life characteristics:

a) service life type;

b) service life;

c) seven service life factors A - G, except where they are defaulted to 1,0,

The context, inputs, method and outputs shall be presented in a structured and clear format.

As short-term exposures typically involve a significant degree of uncertainty, the results shall be considered with care.

A report shall include the following information, wherever applicable:

a) Goal and range definition

b) Exposure programme description, including exposure at pre-tests:

1) general exposure situation, i.e. at outdoor exposure data as latitude, longitude, altitude, distance from coast, special factors like high wind, climate type, etc.;

2) design of the exposure programme, including possible maintenance undertaken for samples, and any accidental deviations thereof;

3) environmental data (including any neighbouring dissimilar components), degradation agent intensities and cycling data;

4) exposure period.

c) Performance evaluation description, including evaluation at pre-tests:

1) methods of measurements or inspections;

2) component data, results of measurements or inspections.

d) Interpretation of data:

1) account for external data sources utilized;

2) specific models or algorithms;

3) results of interpretation;

4) limitations of the interpretation, related to methodology as well as to data;

5) data quality assessment.

e) Critical review:

1) details of reviewers;

2) critical review reports;

3) responses to recommendations.

When the results of the SLP are to be communicated to a third party (i.e. an interested party other than the commissioning client and the commissioned specialist of the study), a third-party report shall be prepared, containing all information indicated above, except what is agreed between the commissioning client and the commissioned specialist to be closed information. This report constitutes a reference document and shall be made available to any third party to whom the communication is made.

Clause 8 along with clause 5 covers the facility context and the predicated estimated service life for reliability and flexibility in use for new facility, typically this is for product data publishers and for design and asset managers. .

This clause adds representation of the context of a product and the predicted service life. The context is provided so that the estimate can be verified. The estimate is provided so that it can be reviewed and used in whole life value assessments.

This clause also adds representation of the economic and environmental impacts of a product, both to-date and ongoing.. Cost is generalized to be an Impact value, thereby ensuring that economic and environmental accounting can be documented. For example, economic cost can be documented along with climate change measures.

Each impact shall be described and the basis of any value shall be given.

NOTE 1 These values can be used to construct aggregate values for aspects of the facility.

Context information shall be provided, including:

a. identification of the instance and its site, facility, system, location

b. identification of the responsible author, appointer

c. date and version

When developing service life predictions for products or components, a specific or generic set of in-use conditions shall be identified for documenting the specific study. This shall account for the specific use of the component, covering the design consequences, and shall comprise a description of the environment, including static and dynamic mechanical stress, at the site where a buit asset is planned. A description of the effects of occupancy (such as water vapour, heat or abrasion) and the principles on which the built asset is operated (e.g. high or low thermal inertia) shall also be included if appropriate.

Estimated service life shall take account of the aspects that will influence the performance and degradation of the components throughout their service life and will therefore modify the reference service life, including:

a. inherent performance of the component;

b. design level of the works;

c. standard of workmanship;

d. indoor environment;

e. outdoor environment;

f. usage conditions;

g. maintenance level.

Predicted/estimated service life. This uses the same property set as for product reference service life (Clause 6) but with the service life type set to EXPECTED SERVICE LIFE. Context grades for evaluations (matching factors A-G) shall be associated to the product or to the nearest space, storey, facility, site or project in which the product occurs, based on a n-point, typically 5-point, scale.

NOTE The context parameters that are neutral or have no effect on service life can be omitted from this data set.

The product utilization shall be given or a utilization of 1,0 (100 %) shall be assumed if not available.

Information shall be provided for:

a) Name and description of impact with a value with unit.

b) Life cycle stage, with duration if applicable.

c) Source

NOTE Justification and documentation of service life data used in Environmental Product Declarations are required by EN 15804. These requirements are based on the ISO 15686 series.

An estimate of the service life of a built aset shall be built up from estimates of the service life of all the relevant components that comprise the built asset. Estimates shall be based on a reference service life.

Data based on reference in-use conditions similar to the object-specific in-use conditions shall be sought to:

— keep the modifying factors as close to unity as possible, thus minimizing the probability of error in the ESL due to uncertainty in the way mechanisms of degradation are taken into account by the modifications;

— minimize the probability that a critical property not encompassed by data becomes the terminal critical property.

NOTE To judge which reference in-use conditions are most similar to, or deviate the least from, the object-specific in-use conditions, consideration can be given only to the in-use conditions or degradation agents known to, or believed to, have the greatest impact on the service life.

Factor based estimation shall consider seven discrete aspects given in Table 2.

Table 2 — Factors and factor categories of the factor method

Rebasing can be applied to convert between types of services life such as from a reference or maximum service life to an estimated life.

L₂ = L₁ * Π (ϕ_2i/ϕ_1i)

L₂ = L₁ * ×  ×  ×  ×  ×  ×  × 

where:

Table 3 — Factors associated with grade

L_f = min (L_c )

where:

If available, data from practical performance of components shall be used for service life estimation, as described in ISO 15686-7. Where appropriate, service life data from practice shall be adjusted using the approach specified in 7.3.1 making a judgement of the conditions in which the available data apply and those to which the component will be exposed in service.

NOTE: Innovative products can provide superior performance and overcome long-standing problems.

For the service life estimation of built assets constructed with innovative components, estimates therefore shall be based on interpretation of the performance of the materials and components in short-term exposure tests. In this case, test procedures failure mode and effect analysis (FMEA) and the application of knowledge of material science shall be used to determine a minimum service life for the innovative component.

The information outputs shall be clearly stated with their confidence.

The outputs shall include:

a. The estimated service life of systems, product types and/or instances

b. The resultant estimated service life of the facility

The context, inputs, method and outputs shall be presented in a structured and clear format.

Clause 9 along with clause 5 covers the appraisal of components in use and their residual service life typically for design and asset managers and their consultants

Context information shall be provided. including the

a. identification of the product or facility

b. identification of the responsible author, appointer

c. date and version

The information inputs shall be clearly stated with their source and confidence.

L₂ = L₁ ×  ×  ×  ×  ×  ×  × 

(take into account actual condition, and anticipated change to degradation agents, facility use, etc )

L_R = A –L_E

Where:

The information outputs shall be clearly stated with their confidence.

The outputs shall include:

a. The residual service life of systems, product types or instances

b. The resultant residual service life of the facility

The context, inputs, method and outputs shall be presented in a structured and clear format.

It shall be decided early in the service life planning how uncertainty in the estimated service life shall be taken into account as the reliability of service life estimation depends on the quality of the data available and the appropriateness of assumptions made. In making service life estimations, the form of the distribution shall be determined if possible; otherwise, it shall be assumed.

NOTE 1 Distributions of various aspects of performance, including service life, can be expected within any group of similar items, including built assets and their components. Due to the number of variables involved and the uncertainties in each, and to the inherent variabilities of built assets, service environments, site workmanship, and future maintenance activities, it is not possible to estimate the service life of a built asset or its components precisely.

Evidence shall be sought regarding reliability of service life estimations based on accelerated exposure tests, by investigating the degree of correlation between in situ performance and laboratory test results.

Defects which cause failures to occur very soon after the occupation of a built asset shall be identified and excluded as these “premature defects” do not necessarily lead to wide-scale failure.

NOTE Generally, a higher degree of uncertainty will be acceptable for maintainable components than for components intended to function without maintenance for the life of the built asset.

Where the uncertainty associated to an appraisal or prediction is significant, values shall be transmitted with indication of the extent of the uncertainty. Communication shall use one of three alternative representations for service life and environmental values specified in 10.2.2 to 10.2.4.

Where a value is known either because the certainty is high or the value is given, then a single value shall be used (see Table 4).

EXAMPLE The climate change impact of an acoustic ceiling tile component is stated as 5 kg CO2e

Table 4 — Simple value

Where the specification or testing leaves some uncertainty, a bounded value shall be used.

Uncertainty affecting a value shall be described by the upper bound, lower bound and modal value. This approach is commonly adopted when representing informal opinions or capturing generalized experience. In the absence of further detail, it shall be represented and analysed as a ‘triangular’ distribution (see Table 22 and Figure 2) as a working assumption for detailed calculations. To define a triangular distribution, three values shall be provided:

— the modal value, being the most typical or likely value;

— the lowest typical or likely value;

— the highest typical or likely value.

See Tables 5 and Figure 3.

NOTE The average (mean) value can be different from the modal value.

EXAMPLE The climate change impact of an acoustic ceiling tile component is estimated as ranging between 2 kg and 10 kg, with the mostly likely value being 5 kg. The mean impact can be estimated as the average of these figures, 5,7 kg.

Table 5 — Triangular probability density table

Figure 2 — Triangular probability density graph

Where there is detailed knowledge of the probable performance, a table distribution of values shall be used.

Where there is sufficient data available, uncertainty affecting a value shall be described using cumulative probability, allowing the representation of any probability distribution, including triangular and normal (Gaussian) distributions. A cumulative probability graph shows the probability of a value (Y-axis) not exceeding a stated value (X-axis) (see Table 6 and Figure 3).

EXAMPLE The climate change impacts of a number of acoustic ceiling tile components have been assessed and summarized (see Table 6 and Figure 4).

Table 6 — Cumulative probability table

Figure 4 — Cumulative probability graph

1. 
   
   Templates and examples
   1. Introduction to templates

The following tables provide:

a. A template for documenting each information exchange

b. A worked example (using fictitious and non-representative values)

• 1. References to other sources for templates

See the Bibliography [6] to [11] for other sources for templates

• 1. Terms used in templates

Topic refers to the name or short description. Measure indicates the expected data type

• 1. Overview

Templates and examples are provided to illustrate the methods in clauses 5 to 10.

• 1. General considerations

Table A.5 details properties describing general considerations applicable in clauses A.6 to A.9. See also Clause 6 and Annex B.6

Table A.5 — template and example for general considerations

• 1. Product/material/assembly identification, characteristics and quantities

Table A.6 details properties describing identification, characteristics and quantities. Measures for quantities and units can vary with product and material type. See Clause 6 and Annex B.6

Table A.6 — template and example for product/material/assembly

• 1. Template and example for product service life testing (clause 7)

The following provides a template and example for the results of product service life testing as an RSL data record. See also Clause 7 and Annex B.7

• 1. Design assessment

Table A.8 provides a template and example for design assessment. See also Clause 8 and Annex B.8

Table A.8 — Design assessment

• 1. In-use assessment of residual service life

Table A.9 provides a template and example for in-use assessment of residual service life. See also Clause 9 and Annex B.9

Table A.9 — template and example for in-use assessment of residual service life.

• 1. Uncertainty

Table A.10 provides a sub-template and example presenting uncertainty. See also Clause 10 and Annex B.10 .

Table A.10 — Presentation of uncertainty

1. 
   
   Data definitions
   1. Introduction to data definitions

IFC contains support for a wide range of built asset topics. The information needed for service life planning and related topics is supported by specific objects (entity types) in the schema (e.g. an object handling functional measures'), but also as general objects handling the technical performance of components and systems, property information (e.g. material) about the components, information about needed measures of care and maintenance etc.

• 1. References to other sources for data definitions

Data definitions can be found at bsDD^[20].

• 1. Use of terms in data definitions

Service life factors: Can be applied to any physical object either as a single occurrence or an aggregation or assembly of physical objects acting as a single object. A service life can have one or more related service life factors according to the ISO 15686 factor method. See 7.4.1.

Grade: The current condition of physical objects can be determined by applying one or more condition criteria. The condition can be determined using either subjective assessment (e.g. condition on a graded scale from 1 to 5 where 1 is very poor and 5 is very good or as new) or by objective assessment using measured values. See 8.3.2.

• 1. Overview

There are several concepts captured in the IFC schema that are relevant to service life planning and that can be applied in a specific subset (view) of the IFC schema about service life planning.. See Tables B.5 to B.10.

• 1. Common attributes

Table B.5 provides IFC data definitions for common attributes. See also Clause 5.

Table B.5 — data definitions for common attributes

• 1. Product/material/assembly characteristics and quantities

Table B.6 provides IFC data definitions for product/material/assembly characteristics and quantities. See also Clause 6. The data definition for Quantity can vary with different products, materials and assemblies.

Table B.6 — IFC data definitions for product/material/assembly characteristics and quantities

• 1. Product service life testing

Table B.7 provides IFC data definitions for product service life testing. See also Clause 7.

Table B.7 — IFC data definitions for product service life testing.

• 1. Design assessment

A product instance or its owning space, storey, facility site or project can have service life context grades (Grade A-G)) associated with it. In each of the seven cases, ’grade’ is appended to the factor name. Each grade can be represented using a five-point verbal scale, or it can be ‘not defined’. Table B.8 provides data definitions for design assessment. See also Clause 8.

Table 2 — IFC Data definitions for design assessment

• 1. In-use assessment of residual service life

Table B.9 provides data definitions for in-use assessment of residual service life. See also Clause 9.

Table B.9 — IFC data definitions for in-use assessment of residual service life

• 1. Uncertainty

Table B.10 provides guidance on data definitions for uncertainty. See also Clause 10.

Table B.10 — IFC data definitions for uncertainty.

Bibliography

[1] ISO 6241, Performance standards in building — Principles for their preparation and factors to be considered

[2] ISO 10303‑11, Industrial automation systems and integration — Product data representation and exchange — Part 11: Description methods: The EXPRESS language reference manual

[3] ISO 10303‑21, Industrial automation systems and integration — Product data representation and exchange — Part 21: Implementation methods: Clear text encoding of the exchange structure

[4] ISO 10303‑28, Industrial automation systems and integration — Product data representation and exchange — Part 28: Implementation methods: XML representations of EXPRESS schemas and data, using XML schemas

[5] ISO 12006‑3, Building construction — Organization of information about construction works — Part 3: Framework for object-oriented information

[6] ISO 14020, Environmental statements and programmes for products — Principles and general requirements

[7] ISO 14021, Environmental labels and declarations — Self-declared environmental claims (Type II environmental labelling)

[8] ISO 14024, Environmental labels and declarations — Type I environmental labelling — Principles and procedures

[9] ISO 14025, Environmental labels and declarations — Type III environmental declarations — Principles and procedures

[10] ISO 14040, Environmental management — Life cycle assessment — Principles and framework

[11] ISO 14044, Environmental management — Life cycle assessment — Requirements and guidelines

[12] ISO 21929‑1, Sustainability in building construction — Sustainability indicators — Part 1: Framework for the development of indicators and a core set of indicators for buildings

[13] ISO 21930, Sustainability in buildings and civil engineering works — Core rules for environmental product declarations of construction products and services

[14] ISO 21931‑1, Sustainability in buildings and civil engineering works — Framework for methods of assessment of the environmental, social and economic performance of construction works as a basis for sustainability assessment — Part 1: Buildings

[15] ISO 29481‑1, Building information modelling — Information delivery manual — Part 1: Methodology and format

[16] EN 15804, Sustainability of construction works — Environmental product declarations — Core rules for the product category of construction products

[17] EN 15942, Sustainability of construction works — Environmental product declarations — Communication format business-to-business

[18] The official website of buildingSMART International is http://www.buildingsmart.com

[19] Most regional buildingSMART groups maintain their own websites accessible from the international site

[20] The buildingSMART Data Dictionary (bsDD) can be accessed at https://www.buildingsmart.org/users/services/buildingsmart-data-dictionary/