Between Full LCA And Energy Certification Methodology A .

Int J Life Cycle Assess (2015) 20:9–22occurring in the use stage: use of primary energy from carrierssuch as natural gas, coal, lignite, biomass, thermal solar collectors, as well as bio-gas and the use of secondary energy asheating oil, liquid gas, heat from coal, gas-oil and bio-massheating plants (OJ No 201, item 2008. 1,240). Additionally,the regulation (OJ No 201, item 2008. 1,240) with regard tothe energy certification methodology states that “alongsidethe use of energy, the related emissions of CO2 associatedwith building can be included.” This means that the second ofthe aspects assessed through certification can be emissions ofCO2; however, in Poland, this is not practiced. The abovementioned energy use (and possible emissions of CO2) isnot analysed in relation to the full life cycle but only forselected areas of the building use such as heating, ventilation as well as hot water. LCA gathers data with regardto a wide spectrum of environmental aspects, not limitedto energy or CO2 emissions but also including the use ofother renewable, as well as non-renewable, resources including: the use of raw materials or pre-made materialsfrom technosphere; land occupation and transformation;emissions of many organic and non-organic compoundsinto the air, water and soil, as well as emissions ofionizing radiation. LCA, in contrast to energy certification, analyses all of the above-mentioned aspects withregard to the entire life cycle of the building.The next element differentiating both tools is the recognition of environmental impact. The LCA methodology assumes, within phase three (LCIA), the assessment of theenvironmental impact based on certain characterisationmodels and impact indicators. As a result, it is possible toqualify and quantify the impact (or damage) on the environment leading to strictly defined environmental issues (impactor damage category) such as: carcinogenicity, respiratory disorders, climate changes (global warming), ozone layer depletion, ecotoxicity and various others. In the case of energycertification, it is difficult to talk about assessing the environmental impact because the process does not really includeindicators recognising levels of impact modelling resemblingthose of LCI. At the most, it can be stated that energy performance certificates use indicators from the LCI level, trackingthe amount of used energy (input indicators are equivalents ofembodied energy indicators or of the cumulative demand forenergy as well as the CO2 emission). It is worth observing thatthe optionally included CO2 emissions in energy certificationdo not relate to CO2 equivalents (as the common unitof impact category global warming or climate changes,which includes and tracks the entire emission of allgreenhouse gases) but only relates to CO2 itself. Assuming this is a substitute of the assessment of environmental impact, it can be established that energycertification, in its widest scope, covers two environmental issues: global warming (climate changes) anddepletion of (energy) sources.112 LCA of buildings—simplificationsThe key question in the context of simplified energy certification and the complex LCA procedures is whether it ispossible to establish a methodological compromise solution.The commonly formulated reservation with regard to LCA isthat it is too time-consuming and too complex. On the otherhand, energy certification is noted as far too simplified (Casals2006). It’s argued that, most often, improvements leading to areduction of energy use in the certified areas, i.e. heating,ventilation and hot water lead to an increased use of buildingmaterials (mainly aluminium, steel, glass, insulation materials) as well as additional HVAC demand (heating, ventilation, air conditioning). This leads to an increased use ofmaterials and energy in other stages of the life cycle, notincluded in energy certification. Only comparing all thechanges with regard to material and energy intensity, as wellas emissions for the full life cycle, would establish whether thegiven innovation is environmentally backed.One of the questions in this process is with regard to whichof the life cycle stages are to be included and which excluded.The following life cycle stages of a building are suggested inEN 15804 2012 established by CEN/TC 350 (EN 158042012): product stage (raw material supply, transport,manufacturing), construction process stage (transport to thebuilding site, building installation), use stage (repair and replacement, refurbishment, energy use, water use) and end oflife (deconstruction, transport, recycling/resume, disposal). Asimilar approach is suggested by International Organizationfor Standardization in standard of ISO 21931 (ISO 21931–12010) (Table 2). The simplifications in life cycle assessmentof buildings were the focus of interest for many authors.Blengini and Carlo (Blengini and Carlo 2010) include 19examples of LCA regarding life cycle stages of buildings.The following are identified: construction materials (production), equipment/interior materials (production), transport,construction, maintenance, use, final disposal (Blengini andCarlo 2010a, b). All analysed cases of LCA included production stages of materials included in the building constructionas well as its usage. Eighteen cases included transport andmaintenance; 14 included construction stages; 63.16 % casesincluded final disposal; equipment materials production stagewas included in (the least) eight examples. Another publication with regard to the link between energy certification andLCA (Bribian et al. 2009) proposes a simplification of LCAand exclusion of the following stages from the life cycle:transport of materials to construction site, erecting of thebuilding, maintenance, repairs and refurbishments, renovation, water usage, demolition/dismantling, transport of wasteand final disposal of waste (Table 2). The ENSLIC BuildingProject is another example of initiative taken with the aim ofLCA’s simplification, and stimulating collaboration betweenLCA experts and building practitioners (Malmqvist et al.

12Int J Life Cycle Assess (2015) 20:9–22Table 2 Life cycle stages of building included in LCA studiesLife cycle stagesModulesCEN/TC 350(EN 15804 2012)ISO TC/59(ISO 21931–1 2010)Bribianet al. 2009Kellenberger andAlthaus 2009Malmqvistet al. 2011I. Product stageRaw material supplyTransportManufacturingTransportBuilding erectionMaintaining order and cleanlinessRepairs and replacementsRefurbishment (renovations andconservations)Energy consumption for heating,cooling, ventilation, hot waterpreparation and lightingWater consumptionWaste seFinal disposal of ludedNo edIncludedNo ExcludedExcludedIncludedIncludedII. Constructionprocess stageIII. Use stageIV. End of life stage2011). The simplified and publicly available LCA tool wasdeveloped as one of the outcomes of the ENSLIC project(ENSLIC). The relevance of simplifications in LCA of building components are also discussed by Kellenberger andAlthaus (Kellenberger and Althaus 2009). The authors madethe comparative analyses between five building componentsby using the cumulative non-renewable energy and ecoindicator 99 (H/A) approaches. They performed the studieswith five levels of detailing (“from all inclusive to fullyreduced”). The LCA results between the extremes differedbetween 15 and 30 % (Kellenberger and Althaus 2009). Otherimportant works related to the residential buildings and therole of particular life cycle stages in the environmentalassessment of buildings with special focus on energyrelated aspects are those of Dixit et al. (2010), Ortizet al. (2009), Optis and Wild ( 2010), Dylewski andAdamczyk ( 2012), Passer et al. (2012) and Rossi et al.(2012).Based on the above considerations, it is possible to state thefollowing:&&Environmental life cycle assessment and energy certification represent related tools both contributing to proenvironment building improvement.The range of data obtained from the use of both toolsdiffers significantly. Energy certification considers proenvironment improvement with regard to the energy usedwith regard to the building usage, whilst LCA takes intoconsideration many more aspects and environmental consequences regarding the full life cycle.&&&&Energy performance certificates as compulsory tools areknown to various stakeholders included in the life cycle ofbuildings whilst LCA is still a novelty.The full LCA can be perceived as too complex and toodifficult to apply in practice, especially with regard to suchcomplex objects of analysis as buildings.Energy certification can be perceived as too simplified,especially in relation to the possibilities and a wide scopeof results obtained with LCA.There are publications that evidence trials to combine bothmethodologies, for example, Bribian et al. (2009).3 Residential buildings under study—descriptionAnalysed were four model detached residential buildingsintended for a four-person family and with the usable spaceof 98.04 m2. The buildings differed with regard to the materialstructure, technology and energy performance. Analysedwere: a masonry conventional building (A1), a masonry passive building (A2), a wooden conventional building (B1) aswell as a wooden passive building (B2) (Fig. 1). All were onestorey buildings with the following plan: entry hall, toilet, day/living room with dining area, kitchen, double bedroom, twosingle rooms, bathroom as well as utility room. The functionalunit was defined as: “provision of 98.04 ms of the usablespace of the buildings fit for use over 100 years and protectionduring that period of the users and objects from harmfulexternal factors.”

Int J Life Cycle Assess (2015) 20:9–22Fig. 1 Buildings selected foranalysis. Source: Lewandowskaet al. (2012)13BUILDING A1conventionalmasonryBUILDING A2passivemasonryDetached residential building with the usable spaceof 98.04m2entry hall, toilet, day room with dining area, kitchen,double bedroom, 2 single rooms, bathroom as wellas utility roomFor each of the above-mentioned buildings, a separatearchitectural project was prepared by the architect’s office.Materials usage, usage parameters, installation as well asusage of energy carriers was calculated individually for eachof the buildings whilst versions A2 and B2 included therequirements with regard to passive buildings. Buildings areassumed to be positioned in a certain relation to the cardinaldirections to maximise the use of sun rays (large windows onthe south wall). This is particularly important in case ofpassive buildings.The construction system and the method of foundation ofthe analysed buildings are assumed as follows (Lewandowskaet al. 2012):&&&&Masonry conventional building (A1): load-bearing structure in a longitudinal arrangement, with load-bearingwalls built using single-layer SOLBET masonry, beamand block ceiling, traditional wood roof with a collarbeam, building foundation laid on a continuous footing,continuous footing made of concrete (thickness 30 cm),laid directly on the bearing soil;Masonry passive building (A2): load-bearing structure ina longitudinal arrangement, with load-bearing walls builtusing double-layer masonry, beam and block ceiling, traditional wood roof with a collar beam, building placed onthe concrete foundation slab (thickness 25 cm) laid on thebearing soil via thermal insulation boards (XPS);A wooden conventional building (B1): load-bearing structure in a longitudinal arrangement, with load-bearingwalls built using a light framework, ceiling and pitchedroof constructed using lattice trusses, building placed onthe concrete continuous footing (thickness 30 cm)founded directly on the bearing soil;A wooden passive building (B2): load-bearing wall structure in a longitudinal arrangement, with load-bearingwalls built using a light framework, ceiling and pitchedroof constructed using lattice trusses, building placed onthe concrete foundation slab (thickness 20 cm) laid on thebearing soil via thermal insulation granules (foam glassgranulate).In case of wooden buildings (B1 and B2), the maximumusage of wood and wood-related materials was assumed. Thewooden elements can be found in the roof (wood shake,BUILDING B1conventionalwoodenBUILDING B2passivewoodenconiferous timber), ceiling structure (OSB, fire-resistant plasterboard), ceiling insulation (wood wool/B1/or cellulose/B2/),external wall structure (OSB, fire-resistant plasterboard), external wall insulation (wood wool/B1/or cellulose /B2/), internal wall structure and gables’ construction (OSB, fire-resistantplasterboard), internal window sills and window frames(softwood) and floor (hardwood floorboard). In cases of buildings A1 and A2, the use of wooden materials was limited tominimum (Table 3).The masonry buildings are considerably weightier. Thetotal mass of building materials used to construct houses A1and A2 was 217 986.7 and 244 282.34 kg, respectively(Table 4). More than 90 % of total mass of masonry buildingsconsists of concrete, natural stone materials and ceramics. Thewooden houses are slighter (B1 150 993.8 and B2 91623.8 kg), and the share of wood and wood-based materialsis total mass more evident (Table 4).The annual consumption of electricity, heat and waterduring the operation of the analysed buildings is presentedin Table 5. More information about system boundaries andinventory data assumed in the presented comparative study forfour residential buildings can be found in Pajchrowski et al.(2014a, b).4 Six variants of LCA detailing (“compromise solutions”)Energy certification in comparison with LCA is a simplification with regard to three areas: scope (life cycle), environmental aspects (LCI) as well as environmental consequences(LCIA) (Fig. 2). Therefore, a modification in those three areashas been proposed.Taking into account the above evidence, it has been agreedto establish and analyse a compromise solution, which wouldcombine the methodological aspects of both LCA and energycertification. Clearly formulating a single solution would appear difficult, and such a task would require establishing of anumber of hybrid approaches. Table 3 illustrates the proposedsix compromise solutions (CS) representing various combinations of selected methodological elements of LCA and energycertification:&CS1 is a reflection of the full LCA, according to which allstages of the entire life cycle of buildings are included; all

14Int J Life Cycle Assess (2015) 20:9–22Table 3 The use of wood and wood-based materials in the analysed housesBuilding moduleRoofing, roofRoof structureCeiling structureCeiling insulationExternal wall structureExternal wall insulationInternal wall structureGables' constructionInternal window sillsFloor finishWindow framesFaçadeMasonry housesWooden housesA1 conventionalA2 passiveB1 conventionalB2 passiveConcrete roof tilesConiferous timberCellular concrete blocksEPSCellular concrete blocksEPSCellular concrete blocksCellular concrete blocksPVCCeramic tilePVCExternal plaster, façade paintConcrete roof tilesConiferous timberCalcium silicate blocksEPSCalcium silicate blocksEPSCalcium silicate blocksCalcium silicate blocksPVCCeramic tilePVCExternal plaster, façade paintWood shakeConiferous timberOSB, fire-resistant plasterboardWood woolOSB, fire-resistant plasterboardWood woolOSB, fire-resistant plasterboardOSB, fire-resistant plasterboardSoftwoodHardwood floorboardWoodSoftwood façade boardWood shakeConiferous timberOSB, fire-resistant plasterboardCelluloseOSB, fire-resistant plasterboardCelluloseOSB, fire-resistant plasterboardOSB, fire-resistant plasterboardSoftwoodHardwood floorboardWoodSoftwood façade boardSource: Pajchrowski et al. (2014a)&environmental aspects characteristic to individual stagesas well as the entire spectrum of environmental issuesincluded in the environmental profile associated with achosen LCIA method (Impact 2002 ) is taken into account. Assumingly, this model should provide a widerange of information about inventory data as well as thetype and size of the impact on environment. The potentialweaknesses of this method are time consumption of aswell as high requirements with regard to the data.CS2 covers the entire life cycle characteristic for the fullLCA; however, the collated inventory data for each of theanalysed stages are analysed in line with energy certification, only with regard to the usage of energy carriers. Thisapproach differs from energy certification, since the analysis covers the typical for energy certificationTable 4 Use of different buildingmaterials in the analysed buildings (as percent share in totalmass of materials)Source: Pajchrowski et al.(2014b)Type of building materials&&environmental consequences, but the analysis is not limited to use stage only but covers all stages of life cycle.CS3: In this case the scope of the analysis includes selected elements of the stage of use typical for energy certification (energy use for: heating, ventilation, hot water), butthe inventory analysis is not limited to the depletion ofenergy carriers and also includes all other input- andoutput-related environmental aspects typical for LCA(material use and emissions). The impact assessmentcovers the whole environmental profile.CS4, model 4, suggests a simplification of life cycleaccording to the majority of guidelines included in thepublication (Bribian et al. 2009) with additionally included non-energy aspects such as: land occupation, use ofwater and wastewater treatment. These aspects with fullMasonry housesWooden housesUnitA1 conventionalA2 passiveB1 conventionalB2 passiveConcreteNatural stone materialsBuilding ceramicsMineral binding materials, aswell as grouts and mortarsWood/wood-based ives and paintsPlasterboardsSumTotal 4100.0150,993.80.24.0100.091,623.8%%%kg

Int J Life Cycle Assess (2015) 20:9–2215Table 5 The annual consumption of electricity, heat and water during the operation of the buildingsHousesA1 traditional masonry A2 Passive masonry B1 traditional wooden B2 passive wooden UnitElectricity: rtv and household equipmentElectricity: lightingElectricity: heatingElectricity: hot tap waterElectricity, ventilationHeat (natural gas), heatingHeat (natural gas), hot tap waterElectricity (ancillary)Hot water (55 C)Cold tres/yearLitres/yearSource: Pajchrowski et al. (2014b)&Fig. 2 Areas of potentialmodification of LCA and energycertification. Source:Lewandowska et al. (2012)EXTENSIONENERGY CERTIFICATIONMore detailed description of all compromise solutions hasbeen shown in Table 6. In the full LCA (CS1), the entire lifecycle of analysed buildings has been assessed whilst, in theremaining cases, the analysis covered only selected elements.The most simplified version is variant SC6. A more detailedoverview of each of the compromise solutions has been included in Table 7.5 LCA calculations for six compromise solutions (CS)For each of the buildings and compromise solutions, inventory data within the scope, shown in Table 7, was entered toSimaPro Analyst v.7.3.0 (Ecoinvent v. 2.2). In full LCA(CS1), combined for all stages of the life cycle (at level “zero”of product system, without suppliers), 474 inventory pointswere gathered for building A1 (masonry conventional), 453for A2 (masonry passive), 584 for B1 (wooden conventional)and 552 for B2 (wooden passive). The completeness of thedata was verified by mass balance. LCIA was carried out withIMPACT 2002 method.Below, Table 8 shows the eco indicator results for sixproposed CS with regard to the four analysed buildings(A1, A2, B1, B2). Figures 3, 4, 5 and 6 show the sameresults in terms of percentage values. The difference inthe height of the graphs equals the difference of ecoindicator values between full LCA/CS1 (100 %) andevery other compromise solution. The results show thehighest truncation level for CS6 identified with energy

linked to both the extraction and the use of non-renewable sources as well as greenhouse gas emissions or acidifying . Feature LCA Energy certification (in Poland) . suming this is a substitute of the assessment of envi-ronmental impact, it can be established that energy ce