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Author: Anh-Migrate

B-11 (Buildings) / B-06 (Products) Definition of the service life of a building product

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Aspect B-11 (Buildings) / B-06 (Products) Definition of the service life of a building product
Description
 The lifespan, or service life, of building components and elements is usually defined as the period of time during which their performance meets or exceeds initial requirements. More detailed definitions can be found in reference work (e.g. the ISO 15686 series [ISO 15686] and [Guidance Paper F 2004] concerning the Construction Products Directive). Service life depends on many parameters, and is one subject of the ISO 15686 series.

Related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions The service life of a product or building component has an influence on several aspects of the use stage of building LCA:

  • It should be taken into account for calculation of the frequency of replacement when the service life of the component is lower than the reference study period (refer to the aspect ‘Replacement frequency: whole number replacement cycles’ for further detail).
  • It should be provided with a maintenance scenario (and valid only under the conditions described with this scenario), as required by EN 15804 (annex A).
  • The performance of products and components usually declines gradually. Whenever possible, the loss of performance should be taken into account if it has an influence on other aspects of the use stage (e.g. modification of the performance of heating and cooling systems, insulation, etc. may have an influence on energy consumption).

The service life of a product or component is influenced by many parameters, notably the indoor and outdoor environments, maintenance level, design of the product, etc. (see ISO 15868-8 for further information). When providing information related to service life for an EPD, ISO 15804 requires that the intended use and in-use conditions of the product or system be specified and documented (EN 15804, Annex A).

When developing LCA at the building scale on the basis of several EPDs, it should be verified that the declared service lives and in-use conditions are compatible with the specifics of the building (notably its location and maintenance scenarios).

Only end of life related to loss of performance should be taken into account in the base-case scenario. End of life related to obsolescence (e.g. replacement of the product system by a newly developed or more efficient one before the end of life) may, however, be assessed in a complementary assessment. For more information on obsolescence please refer to ISO 15686-1 (Chapter 7).
Rules from:
 EN 15978:
7.4.4.1 General
8.3 Time related characteristics
8.6.3 Scenarios for maintenance, repair, replacement

EN 15804:
6.3.3. Reference service life
7.3.3.1 B1–B5 use stage related to the building fabric
Annex A
Guidance
 The RSL could be based on empirical, probabilistic or statistical data, but should always take into account the intended use (description of use) as described in ISO 15686-1, -2, -7 and -8 [EN 15804, Annex A].RSL should be determined on the basis of:

  • individual EPDs (cradle to gate with corresponding option, or cradle to grave);
  • client requirements and current practices;
  • product and component manufacturers’ information;
  • existing applicable standards such as ISO 15686-1, -2, -7 and -8;
  • the conventional service life in a national context or within an LCA software package for buildings.

It is expected that some service life data may be missing for the assessment at the building scale. In this case, several additional sources may be used to determine the service life of the product or system:

  • publicly available or commercial databases, including in some cases those related to whole-life costing;
  • research group publications and initiatives, such as the joint CIB/RILEM technical committee (CIB W080/RILEM TC 175-SLM);
  • scientific publications, e.g. from the DBMC conferences (International Conference on Durability of Building Materials and Components). More publications are available from the ICONDA database).

For building products, it may be useful to use conventional values for the respective product category (e.g. in a national context or within an EPD programme), if available. For example, the EOTA guide in Europe states some commonly agreed service lives:

  • 10 years for easily replaceable products (e.g. paints);
  • 25 years for products that can be replaced with some minor effort (e.g. façade, windows, building-integrated photovoltaics, etc.);
  • 50 years for products that are difficult to replace (e.g. thermal break);
  • 100 years for irreplaceable products (e.g. structural bricks, concrete columns, etc.).

Refer to the aspects ‘Distinction between Modules B2, B3, B4 and B5’ and B-14 ‘Replacement frequency’ for further guidance on how to interpret and use RSLs for product and building LCA.

B-12 (Buildings) / B-07 (Products) Replacement frequency

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Aspect B-12 Replacement frequency
Description
 The frequency of replacement is related to the reference study period and the reference service life of the component to be replaced. The ratio between them could lead to a partial number of replacements (e.g. where the reference study period is 30 years but the reference service life for a component is 20 years). Should replacement cycles be calculated as ‘whole-number/full number’ of replacements, or does it make sense to calculate ‘proportionate/partial’ cycles of replacement?

related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions As the baseline scenario, replacement cycles have to be calculated in whole numbers, according to EN 15978 and EN 15804 (examples are given there). Only whole numbers of replacements are allowed (no partial replacements). The number of replacements is related to the reference study period and the reference service life of the component to replace. The number of replacements must be rounded up unless justified.In order to show the effect of improved durability, a scenario with partial replacement cycles can be made. This scenario has to be documented and justified, and a sensitivity analysis conducted by comparison with the baseline scenario.
Rules from:
 EN 15978:
8.6.4 Scenarios for refurbishment – Module B5
9.3.3 Replaceable components and number of replacements

EN 15804:
6.3.4.4.2 B1–B5 Use stage information modules related to the building fabric: – B4 Replacement

ILCD:
6.10.3 Considered alternatives, the functional unit, and assumptions
Provisions: 6.10 Comparisons between systems

Guidance
 Partial replacement numbers should be avoided. Replacement numbers should be rounded up, unless justified as described below:
The last replacement of components may be skipped, provided:
–       the component is not essential to security, health or comfort;
–       the absence of replacement is based on actual practice;
–       the final replacement occurs during the last 10% of the study period;
–       a specific maintenance scenario is developed in this case.
This guidance needs to be applied homogeneously in comparisons. For example, for a study period of 50 years, in the case of an internal paint with a 15-year reference service life the last replacement could be ignored (i.e. two replacements rather than three).

B-13 Replacement with screening LCA

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Aspect B-13 Replacement with screening LCA
Description
 The replacement module covers the complete replacement of components and building parts if their reference service life is lower than the reference study period. Replacement is optional in the context of a screening LCA.

related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions Replacement is optional in the context of a screening LCA.The replacement procedure refers only to planned action in response to anticipated losses of performance of building components and building parts. Replacements should be considered when the reference service life (or eventual design life) of a product or building part is lower than the reference study period.The replacement scenario may cover some of the elements in the following list (item marked with a * are suggested):

  • roof*;
  • windows*;
  • floor finishes and coverings*;
  • refrigeration* and coolants;
  • decorative wall finishes and coatings (e.g. wallpaper, paints);
  • doors;
  • heating, cooling and lighting equipment, and any power-generating equipment (e.g. wind turbines, PV or solar heating)*;
  • equipment for internal transport (e.g. lifts, escalators)*;
  • water and sewerage systems;
  • electrical distribution system.

Replacement of load-bearing structure, exterior and basement walls, floor slabs and foundation should not be considered unless justified, as they usually entail significant building modification.

In any case, the boundaries of the maintenance scenario should be clearly stated.

A replacement scenario at the building scale may be determined on the basis of:

  • individual EPD (cradle to gate with corresponding option, or cradle to grave);
  • client requirements and current practices;
  • product and component manufacturers’ information;
  • existing applicable standards such as ISO 15686-1, -2, -7 and -8 [ISO 15686].

Building modifications in response to unexpected events (e.g. flood, inappropriate use or vandalism) should be considered as reparation (B3), and are thus optional in the context of a screening LCA.

According to EN 15978, the boundary for replacement should include:

  • production of the replaced component and ancillary products;
  • transportation of the replaced component and ancillary products, including production impacts and the aspects of any losses of materials during transportation;
  • the replacement process for the replaced components and ancillary products;
  • waste management of the removed component and of ancillary products;
  • the end-of-life stage of the removed component and of ancillary products.

However, in the context of a screening LCA, only the production of the replaced component need be included.

The frequency of replacement may be determined according to the ‘replacement frequency’ aspect of the present guide.
Rules from:
 EN 15978:
7.4.4.1 General
7.4.4.5 Boundary for replacement (Module B4)
8.3 Time related characteristics
8.6.3 Scenarios for maintenance, repair, replacement

EN 15804:
6.3.3. Reference service life
6.3.4.4.2  – B4 Replacement
7.3.3.1 B1–B5 use stage related to the building fabric
Annex A
Guidance
 If possible, the overall replacement scenario should be consistent with respect to the building structure (e.g. replacement of coating is mandatory when replacing the support). In addition, LCA of an existing building should take into account actual and established practices (real-life data) specific to that particular building.

B-14 Replacement with simplified LCA

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Aspect B-14 Replacement with simplified LCA
Description
 The replacement module covers the complete replacement of components and building parts if their reference service life is lower than the reference study period. Replacement is mandatory for a limited set of building parts and components in the context of a simplified LCA.

related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions The replacement procedure refers only to planned action in response to anticipated losses of performance of building components and building parts. Replacements should be considered when the reference service life (or eventual design life) of a product or building part is lower than the reference study period.The replacement scenario should cover at least the elements in the following list (item marked with a * are suggested):

  • roof*;
  • windows*;
  • floor finishes and coverings*;
  • refrigeration* and coolants;
  • decorative wall finishes and coatings (e.g. wallpaper, paints);
  • doors;
  • heating, cooling and lighting equipment, and any power-generating equipment (e.g. wind turbines, PV or solar heating)*;
  • equipment for internal transport (e.g. lifts, escalators)*;
  • water and sewerage systems;
  • electrical distribution system.

The replacement of load-bearing structure, exterior and basement walls, floor slabs and foundation should not be considered unless justified, as it usually entails significant building modification.

In any case the boundaries of the maintenance scenario should be clearly stated.

A replacement scenario at the building scale should be determined on the basis of:

  • individual EPD (cradle to gate with corresponding option, or cradle to grave);
  • client requirements and current practices;
  • product and component manufacturers’ information;
  • existing applicable standards such as ISO 15686-1, -2, -7 and -8 [ISO 15686].

Building modifications in response to unexpected events (e.g. flood, inappropriate use or vandalism) should be considered as reparation (B3), and are thus optional in the context of a simplified LCA.

According to EN 15978, the boundary for replacement should include:

  • production of the replaced component and ancillary products;
  • transportation of the replaced component and ancillary products, including production impacts and the aspects of any losses of materials during transportation;
  • the replacement process for the replaced components and ancillary products;
  • waste management of the removed component and of ancillary products;
  • the end-of-life stage of the removed component and of ancillary products.

However, in the context of a simplified LCA, only the production of the replaced component need be included.

The frequency of replacement may be determined according to the ‘replacement frequency’ aspect of the present guide.
Rules from:
 EN 15978:7.4.4.1 General

7.4.4.5 Boundary for replacement (Module B4)

8.3 Time related characteristics

8.6.3 Scenarios for maintenance, repair, replacement

EN 15804:

6.3.3. Reference service life

6.3.4.4.2 – B4 Replacement

7.3.3.1 B1–B5 use stage related to the building fabric

Annex A
Guidance
 The overall replacement scenario should be consistent with respect to the building structure (e.g. replacement of coating is mandatory when replacing the support).In addition, LCA of an existing building should take into account actual and established practices (real-life data) specific to that particular building.As replacement scenarios are based on the RSLs of building components and building parts, it should be noted that the RSL could be based on empirical, probabilistic or statistical data, and should always taking into account the intended use (description of use) as described in ISO 15686-1, -2, -7 and -8 [EN 15804, Annex A]. Furthermore, a component manufacturer cannot be held responsible for the actual design of the building or the use and application of the product, environment, workmanship or use [EN 15804, Annex A].

Thus:

  • The overall replacement scenario should be consistent with the maintenance scenario.
  • Both maintenance and replacement scenarios should be based on reliable service life data, either included in the EPD, directly provided by the manufacturer, or based on sound research work.

For an existing building, if a component has failed before its reference service life because of inappropriate maintenance, it may be considered as belonging to the repair module instead.

B-15 Replacement with complete LCA

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Aspect B-15 Replacement with complete LCA
Description
 The replacement module covers the complete replacement of components and building parts if their reference service life is lower than the reference study period.

related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions The replacement procedure refers only to planned action in response to anticipated losses of performance of building components and building parts. Replacements should be considered when the reference service life (or eventual design life) of a product or building part is lower than the reference study period.A replacement scenario at the building scale should be determined on the basis of:

  • individual EPD (cradle to gate with corresponding option, or cradle to grave);
  • client requirements and current practices;
  • product and component manufacturers’ information;
  • existing applicable standards such as ISO 15686-1, -2, -7 and -8 [ISO 15686].

Building modifications in response to unexpected events (e.g. flood, inappropriate use or vandalism) should be considered as reparation (B3).

According to EN 15978, the boundary for replacement should include:

  • production of the replaced component and ancillary products;
  • transportation of the replaced component and ancillary products, including production impacts and the aspects of any losses of materials during transportation;
  • the replacement process for the replaced components and ancillary products;
  • waste management of the removed component and of ancillary products;
  • the end-of-life stage of the removed component and of ancillary products.

Water and energy usage related to the replacement process should always be included.

The frequency of replacement should be determined according to the ‘replacement frequency’ aspect of the present guide.
Rules from:
 EN 15978:
7.4.4.1 General
7.4.4.5 Boundary for replacement (Module B4)
8.3 Time related characteristics
8.6.3 Scenarios for maintenance, repair, replacement

EN 15804:

6.3.3. Reference service life

6.3.4.4.2  – B4 Replacement

7.3.3.1 B1–B5 use stage related to the building fabric

Annex A
Guidance
 The overall replacement scenario should be consistent with respect to the building structure (e.g. replacement of coating is mandatory when replacing the support). In addition, LCA of existing building should take into account actual and established practices (real-life data) specific to that particular building.As replacement scenarios are based on the RSLs of building components and building parts, it should be noted that the RSL could be based on empirical, probabilistic or statistical data, and should always taking into account the intended use (description of use) as described in ISO 15686-1, -2, -7 and -8 [EN 15804, Annex A]. Furthermore, a component manufacturer cannot be held responsible for the actual design of the building or the use and application of the product, environment, workmanship or use[EN 15804, Annex A].Thus:

  • The overall replacement scenario should be consistent with the maintenance scenario.
  • Both maintenance and replacement scenarios should be based on reliable service life data, either included in the EPD, directly provided by the manufacturer, or based on sound research work.

For an existing building, if a component has failed before its reference service life because of inappropriate maintenance, it may be considered as belonging to the repair module instead

For a new building, replacement frequency and more generally the replacement scenario should be based on service life planning and service life prediction, as described by ISO 15686 series [ISO 15686]. It should be noted that: service life planning can only address foreseeable changes. Since service life planning is concerned with foreseeable risks, it is not applicable to the estimation of obsolescence […] or to defective performance resulting from unforeseeable events or processes [ISO 15686-1, part B.8.2.]. Both cases may be accounted for in the case of existing buildings whenever specific data are available.

The progressive loss of performance of some components has an impact on the overall behaviour of the building (e.g. loss of performance of insulation may lead to an increase of energy demand due to heating). If sufficient data are available these aspects should be addressed by using a sensitivity analysis.

B-16 Refurbishment for screening, simplified and complete LCA

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Aspect B-16 Refurbishment for screening, simplified and complete LCA
Description
 Refurbishment activities refer to the change of major elements or change of use in a building.Do we need to take refurbishment into account in a building LCA?

related study objective

 ☒ stand-alone LCA ☒ comparative assertion

related study phase

 ☒ ☐ ☐ ☐ ☐
goal and scope definition inventory analysis (LCI) impact assessment (LCIA) interpretation reporting

relevant for
new buildings existing buildings construction products screening LCA simplified LCA complete LCA
Provisions Refer to provisions in the aspect ‘Distinction between Modules B2, B3, B4 and B5’.
Rules from:
 EN 15978:
7.4.4.1 General
7.4.4.6 Boundary for refurbishment (Module B5)
8.3 Time related characteristics
8.6.4 Scenarios for refurbishment

EN 15804:

6.3.4.4.2 B1–B5 Use stage information modules related to the building fabric:

7.3.3.1 B1–B5 Use stage related to the building fabric
Guidance
 Refer to guidance in the aspect ‘Distinction between Modules B2, B3, B4 and B5’. For example, it is recommended that a refurbishment scenario be developed in the case of a significant reference study period (>100 years); as modification of the building use is expected over such a period of time. A refurbishment scenario could also be developed if the reference study period is higher than the reference service life of load-bearing components and structural elements.

7.6 Module B5 – Refurbishment

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No specific aspects are given for module B5 for products. Please refer to EN 15804 for information concerning this module.

7.7 Module B6 – Operational energy use.

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7.7  Module B6 – Operational energy use.