Tag: Study type: Screening LCA

B-10 Assessment of different repair and maintenance alternatives

Written on 21. October 2012.

*Aspect*		B-10 Assessment of different repair and maintenance alternatives
*Description*		The performance of a product often depends on maintenance. However, several maintenance schemes may be developed for the same product, depending on the owner’s requirements and the building specifics. In the case of the repair module, several repair alternatives may also be considered, notably for an existing building.
*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*	When considering and comparing several repair or maintenance scenarios, the following items should be taken into account and documented: Any deviation from the scenario contained in EPDs should be justified and documented. Overall repair scenarios should be consistent with the RSL of each component or building part, notably by referring to the ISO 15686 series [ISO 15686]. The consequences of the repair scenario should be studied (the influence on future maintenance and replacement scenarios, and the impacts on building performance).
*Rules from:*	*EN 15978: 7.4.4.1 General 7.4.4.4 Boundary for repair (module B3) 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 – B3 Reparation 7.3.3.1 B1-B5 use stage related to the building fabric Annex A
*Guidance*	The overall repair scenario should be consistent with respect to the building structure (e.g. replacement of coating is mandatory if repairing the support).Figure 17: Replacement cycles [EN 15804]The boundaries of the repair and maintenance modules should be similar in the case of comparison (refer to ‘Repair with complete LCA’ for further guidance).It is recommended that sensitivity analysis be used when comparing different scenarios.

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

Written on 21. October 2012.

*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-13 Replacement with screening LCA

Written on 21. October 2012.

*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-16 Refurbishment for screening, simplified and complete LCA

Written on 21. October 2012.

*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.

B-08 Modelling of energy use

Written on 21. October 2012.

Aspect

B-08 Modelling of energy use

Description

Is B6 relevant at a product level? How should the operational energy use be modelled?

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

Energy used by products during the use stage should be assessed in terms of importance. For a product, a scenario may be defined if the product is relevant for the energy supply of a building. However, the actual operational energy use can only be given for a building; data for this module for products are always based on a specific scenario, and do not necessarily apply to other situations.

Rules from:

EN 15804

6.2.5 B6–B7, use stage, information modules related to the operation of the building

Guidance

The regulated energy use (the energy use covered by national building regulations in Member States) of building-integrated technical systems is determined by the design of the building and the use of the building.Regulated energy use reported in Module B6 would normally be provided at a building level through modelling with the relevant national system derived from the Energy Performance in Buildings Directive.At a product level, it is not possible to model the relevant regulated operational energy use related to the product, because it is dependent on all the other parts of the building, although the product could be included within a ‘model’ building and a building assessment undertaken.

If a product requires non-regulated energy to use it – for example a blind that requires electricity for operation, or an intelligently glazed panel that requires electricity to switch to clear from opaque, or a grey water system that requires energy for pumping – then this energy use should also be modelled in Module B6. This would need to be based on a scenario for use, such as the number of operations per day. The results of Module B6 should be separated from the other modules. Additional data to support the development of relevant scenarios on building level should be provided if relevant in the product LCA study, even if the use stage modules are not assessed at the product level.

B-17 Operational energy demand for new buildings – Boundaries and scenarios for screening LCA

Written on 21. October 2012.

*Aspect*		B-17 Operational energy demand for new buildings – Boundaries and scenarios for screening LCA
*Description*		Several parameters can influence the results of the energy demand at the operational stage of buildings. Among others, the selection of uses (i.e. building-related or non-building-related uses) has a major significance on the energy demand. European standards (EN 15804/EN 15978) recommend that priority be given to taking building-related uses into account; however, it is obvious that non-building-related appliances significantly influence the energy needs of building-related uses (e.g. the thermal gain of appliances decreases the level of heating demand). How can this aspect can be addressed in screening LCA of new buildings?
*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*	For screening LCA of new buildings, building-related uses should be accounted for. Other uses may be included according to the object of the assessment. For screening LCA, simplified approaches for calculation or estimation of the operational energy use may be used.
*Rules from:*	*EN 15978:7.4.4.7 Boundaries for operational energy use* 8.6.5 Scenarios for operational energy use – Module B6
*Guidance*	For screening LCA, building-related uses defined according to the Energy Performance of Buildings Directive (2002/91/EC) should be accounted for, possibly by the use of simplified calculation methods or estimates, as specific, detailed energy performance calculations may not be available in the early design stages of a building.The expected performance target for the building may be used to estimate the operational building energy demand. The performance may correspond either to energy label targets or to reference levels set by a national regulation. Energy demand should at least be calculated for building-related uses covered by the EPBD directive (heating, cooling and air conditioning, ventilation, domestic hot water, lightning and auxiliary energy used for pumps, control and automation).The breakdown of the energy demand for each energy carrier may be derived from the energy target according to the expected integrated systems (boiler, ventilation, lighting and cooling systems etc.). Other energy uses may be included and calculated with the help of conventional or statistical data. Link between energy consumption values and environmental impacts Once the energy consumption values are calculated, they need to be associated with generic or specific LCA data for the corresponding process. For example, the number of kWh of electricity in a French building project should be associated with the generic LCA data representing the average mix for the French context. Other energy sources such as fuel, natural gas, wood and district heating also need a generic LCA data describing only the combustion. To this purpose, the infrastructure (e.g. the boilers) should be accounted for as technical equipment. This equipment contributes to the embodied impacts of a building along with the building products.

B-20 Operational energy demand for existing buildings – Boundaries and scenarios

Written on 21. October 2012.

*Aspect*		B-20 Operational energy demand for existing buildings – Boundaries and scenarios
*Description*		Several parameters can influence the results of the energy demand at the operational stage of buildings. Among others, the selection of uses (i.e. building-related or non-building-related uses) has a major significance on the energy demand. European standards (EN 15804/EN 15978) recommend that priority be given to taking building-related uses into account; however, it is obvious that non-building-related appliances significantly influence the energy needs of building-related uses (e.g. the thermal gain of appliances decreases the level of heating demand). Moreover, the global gain obtained by technology mixing building energy uses and non-building-related uses (e.g. appliances such as dishwashers and washing machines using domestic hot water produced by solar thermal panels) can be taken into account only if all operational energy uses are also considered into the assessment. The following section aims at providing guidance for screening, simplified and complete LCA of existing buildings.
*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*	For existing buildings, measured historical data consumption should be used, if available and applicable. Building-related uses and non-building-related uses may be taken into account according to the goal and the scope of the study.
*Rules from:*	*EN 15978: 7.4.4.7 Boundaries for operational energy use* 8.6.5 Scenarios for operational energy use – Module B6
*Guidance*	For existing buildings, if measured historical data consumption are available and applicable (i.e. the objective and the scope of the study are consistent with available data, and future changes in the existing building will not impact on the energy uses), they should be used to calculate the energy demand.Note: the level of detail of energy measurement should allow its use for LCA assessment (i.e. the breakdown of the operational energy demand should be available for each energy carrier). When measured data are available for each energy carrier, building-related and non-building-related uses should be accounted for, as energy monitoring usually does not permit uses to be differentiated. This applies to screening, simplified and complete LCA. For the calculation of energy demand of building-related uses, methods and tools developed by EPA-NR projects may be used.

B-21 Operational energy demand for new buildings – Consideration of user behaviour

Written on 21. October 2012.

*Aspect*		B-21 Operational energy demand for new buildings – Consideration of user behaviour
*Description*		Several parameters influence the results of the energy calculation demand at the operational stage of buildings. Among others, user behaviour may have a major significance on the energy needs. The following section aims at providing guidance for screening, simplified and complete LCA of new buildings.
*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*	For stand-alone LCA, scenarios may reflect statistical, conventional or specific user behaviour.For comparative assertions, behaviour scenarios for the calculation of energy use should be identical for each alternative. Any deviation between scenarios should be reported and justified.
*Rules from:*	*EN 15978: 8.6.5 Scenarios for operational energy use – Module B6*
*Guidance*	For stand-alone LCA, sensitivity analysis should be carried out in order to estimate the significance of the use of a specific scenario instead of a conventional one.

B-22 Operational energy demand for existing buildings – Consideration of user behaviour

Written on 21. October 2012.

*Aspect*		B-22 Operational energy demand for existing buildings – Consideration of user behaviour
*Description*		Several parameters influence the results of the energy calculation demand at the operational stage of buildings. Among others, user behaviour may have a major significance on the energy needs. The following section aims at providing guidance for screening, simplified and complete LCA of existing buildings, and the possibility of taking user behaviour into account regarding the goal and the scope of the study.
*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*	For existing buildings, if measured consumption data are available and applicable for the LCA analysis, user behaviour should be taken into account. Otherwise, the same guidance as for new buildings should be applied.
*Rules from:*	*EN 15978:8.6.5 Scenarios for operational energy use – Module B6*
*Guidance*	For stand-alone LCA of existing buildings, if measured historical consumption data are available and applicable (i.e. the objective and the scope of the study are consistent with available data, and future changes in the existing building will not impact on the energy uses), they should be used to calculate the energy demand.Otherwise, scenarios should reflect statistical or conventional user behaviour. Scenarios reflecting specific user behaviour may be used, but sensitivity analysis should be performed in order to provide evidence of the significance of this deviation. For comparative study of refurbishment alternatives for existing buildings, four different types of operation should be considered: rehabilitation; reference rehabilitation; complete demolition and new construction; maintenance of an existing building (maintain performances during a given period). A rehabilitation operation consists of a deconstruction operation (removal of products) and a reconstruction operation (adding new products to replace discarded ones). Reference rehabilitation is a generic rehabilitation that implies the use of standard construction materials, designs and processes. If historical data and/or energy monitoring and reflecting user behaviour (e.g. number of users, occupancy scenario etc.) are available, and if they are applicable (i.e. alternatives for refurbishment do not consider a change of use or other major modification of building systems or occupancy) , then scenarios derived from such data should be used to calculate the energy demand for each alternative. Otherwise, scenarios should reflect statistical or conventional user behaviour. The same scenario should be used for each alternative.

B-24 Dynamic LCA data for assessing the impact of electricity consumption

Written on 21. October 2012.

*Aspect*		B-24 Dynamic LCA data for assessing the impact of electricity consumption
*Description*		Energy sources for electricity production may vary significantly according to the season (winter or summer months), the day (weekdays, weekends) and the time within a day. Environmental impacts are strongly influenced by the decision to use annual energy data (i.e. average LCA data) or energy data based on a shorter period (monthly, daily or hourly).
*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*	Annual average datasets for electricity production should be used in the baseline scenario. Deviating data can be analysed in additional scenarios with transparent documentation and a sensitivity analysis.
*Rules from:*	*EN 15978*: Not mentioned
*Guidance*	Dynamic LCA data can be produced by using the hourly data provided by electricity suppliers in each national context. For example, in France, RTE provides hourly data, broken down by source: fossil, hydropower or nuclear energy Based on these proportions, and LCI/LCIA data corresponding to each energy source, dynamic LCA data can be calculated. (Note: the LCI/LCIA data statically aggregate elementary flows.) Such dynamic LCA data can also be linked to models to predict the environmental impacts in a dynamic way (although very few LCA tools for buildings currently provide such assessment). More detailed information on this aspect can be found e.g. in a French PhD thesis by G. Herfray [Herfray 2011] or in [LoRe-LCA 2011]