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The changing role of life cycle phases, subsystems and materials in theLCA of low energy buildings

Gian Andrea Blengini a,b,*, Tiziana Di Carlo c

a DISPEA - Department of Production Systems and Business Economics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italyb CNR-IGAG: Institute of Environmental Geology and Geo-Engineering, Corso Duca degli Abruzzi 24, 10129 Turin, Italyc DICAS - Department of Housing and City, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy

1. Introduction

Lowering energy intensity and environmental impacts of

buildings is increasingly becoming a priority in energy and

environmental policies in European countries. In Italy, such

policies are being integrated in energy strategies and building

regulations at different scales, from national to local, mainly

through direct and indirect actions that are aimed at decreasing

energy requirements during the use phase, with focus on winter

heating.

Although it is reasonable to tackle priorities for improving

the environmental sustainability of buildings starting from the

most energy intensive elements, it should be pointed out that

not only is the use phase a source of environmental concern, but

also the whole life cycle. The overall environmental impacts of

buildings extend beyond the use phase, as they also encompass

the embodied energy and environmental burdens related to

resource extraction and manufacturing, construction activities,

as well as dismantling and construction waste disposal at end-

of-life (EOL).

Moreover, life cycle impacts are highly inter-dependent, as one

phase can influence one or more of the others. For instance, the

selection of building materials can reduce heat requirement, but

might also increase embodied energy and transport-related

impacts or affect the service duration of the whole building, and

could even influence the generation of recyclable (or disposable)

demolition waste.

Thus, interest in understanding energy use, consumption of

natural resources and pollutant emissions in a life cycle

perspective is growing, as acknowledged in a number of studies

[1–13]. While in some of these it has been confirmed that

operation energy is by far the most important contributor to life

cycle impacts of conventional buildings [1–4,6,8], in some other

cases [7,10–12] it has been pointed out that, especially for new

and low energy buildings, the relative role and the importance of

life cycle phases are changing. According to Huberman and

Pearlmutter [12], the embodiedenergy can beup to60%of the life

cycle energy.

Therefore, the lower the operation energy, the more important

it is to adopt a life cycle approach. Hence, an overall judgment on

building sustainability should encompass all the life phases and

should be based on an objective and internationally recognised

Energy and Buildings 42 (2010) 869–880

A R T I C L E I N F O

Article history:Received 2 June 2009

Received in revised form 11 December 2009

Accepted 26 December 2009

Keywords:

LCA

Sustainability

Low energy building

End-of-life

Recycling potential

A B S T R A C T

A detailed Life Cycle Assessment (LCA) has beenconductedon a lowenergy family house recently built inNorthern Italy. The yearly net winter heat requirement is 10 kWh/m2, while the same unit with legal

standard insulation would require 110 kWh/m2. As the building was claimed to be sustainable on the

basis of its outstanding energy saving performances, an ex post LCA was set up to understand whether,

and to what extent, the positive judgement could be confirmed in a life cycle perspective. The dramatic

contribution of materials-related impacts emerged. The shell-embedded materials represented the

highest relative contribution, but maintenance operations also played a major role. The contributions of

plants, building process and transportation were minor. The important role of the recycling potential

also emerged. Unlike standard buildings, where heating-related impacts overshadow the rest of the life

cycle, there is no single dominating item or aspect. Rather, several of them play equally important roles.

The study has confirmed that the initial goalof environmental sustainability was reached,but to a much

lower extent than previously thought. In comparison to a standard house, while the winter heat

requirement was reduced by a ratio of 10:1, the life cycle energy was only reduced by 2.1:1 and the

carbon footprint by 2.2:1.

ß 2010 Elsevier B.V. All rights reserved.

* Corresponding author at: DISPEA - Department of Production Systems and

Business Economics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129

Turin, Italy. Tel.: +39 011 209 72 88; fax: +39 011 090 72 99.

E-mail address: [email protected] (G.A. Blengini).

Contents lists available at ScienceDirect

Energy and Buildings

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / e n b u i l d

0378-7788/$ – see front matterß 2010 Elsevier B.V. All rights reserved.

doi:10.1016/j.enbuild.2009.12.009

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methodology such as the Life Cycle Assessment (LCA), accordingto

the ISO 14040 and 14044 standards [14,15].

Official statistics [16] support the need for energy saving

policies that incorporate the life cycle approach. The use of

buildings in Italy roughly corresponds to 31% of the final energy

use and greenhouse emissions throughout the country, but, when

the manufacturing of construction materials (cement, bricks, glass,

ceramics, etc.) is included, and when building activities are

considered, the final energy use and greenhouse emissions rise to

37 and 41%, respectively.

On the basis of these preliminary considerations, the paper

presents the results of a detailed LCA application to a low energy

single family house that has recently been built (end of 2007) in

Northern Italy. The building, located in the town of Morozzo, in

Piedmont, was designed with an overall energy saving objective

that is well beyond the most restrictive Italian and local

regulations: one tenth of the maximum winter heat requirement

allowed for a standard building.

The house in Morozzo was selected by Regione Piemonte (the

regional public administration) as an outstanding example of a

very low energy building. A financial contribution was awarded to

cover the extra costs of the thermal insulation, finishes and plants

in order to decrease the winter heat requirement from 110 kWh/

(m2 year) to around 10 kWh/m2. As a term of comparison, theexisting building assets in the area under study show an average

heat requirement of about 200 kWh/m2.

As the building was claimed to be sustainable on the basis of its

outstanding energy saving performance, an ex post LCA research

programme was set up to understand whether,and to what extent,

the benefits that have been obtained after having drastically

lowered the energy requirement for winter heating and domestic

hot water (DHW) could be confirmed in a life cycle perspective.

Low energy buildings are in fact typically characterised by higher

embodied environmental burdens which might reduce, or even

cancel, the achieved environmental benefits.

Bearing this in mind, a detailed LCA model was set up in

compliance with international standards and guidelines

[14,15,17,18]. The LCA model of the low energy house wascompared with a second model relevant to the same house, but

with a standard winter energy requirement and conventional

plants. In order to better understand the role and the significance

of life cycle phases andsubsystemsand pointout thekey elements,

detailed and quantitative field measured data were collected on

building shell and plants materials, as well as on the building

process.

As the demolition and EOL of materials have rarely been

addressed in previous LCA studies [2,6,7,19], in some cases being

excluded [3,12] and often being analysed using literature data

[7,8,11,20–23], special attentionwas paid to modela realisticpost-

mortem scenario, taking into account the knowledge gathered in

previous studies [2].

Due to the fact that the design for dismantling concept had not

been adopted during the design process, only for some of the

building materials was it reasonably possible to assume a selective

dismantling and subsequent recycling or reuse. Therefore, it was

only possible to consider the recycling potentials for some

materials, as discussed in other studies [2,19,21,23], while, for

other materials, the only practicable option was landfill or

incineration.

The methodology and the results here presented can also be

useful to address simplifications in future LCAs in the built

environment. While it is certainly true that there is need for LCA-

based tools in the building industry, the methodology is often

regarded as too complicated, data and knowledge intensive, and

time consuming. The role of simplification in LCAs of whole

buildings or parts of it, like the one presented by Kellenberger andAlthaus [24], is in fact a delicate issue that should be dealt with

carefully, before LCA can become fully operational in the building

sector. Detailed LCAs cannot be easily applied to routine design,

but they can be useful to understand how and where simplifica-

tions could help.

On the basis of the analysis here presented, the life cycle

approach should be adopted as a complement to existing energy

saving and energy certification schemes, which are too often

lacking in a comprehensive approach that would enhance their

effectiveness and avoid problem shifting.

2. Description of the low energy house

The low energy building under study is an individual familyhouse, which is the main home of four occupants. It is located 80 km

south of Turin and built on three levels, with a garage underneath

two heated floors. The main geographical and climatic data, as well

as some relevant building features are reported in Fig. 1.

Fig. 1. Main features and climatic data of the house in Morozzo.

G.A. Blengini, T. Di Carlo/ Energy and Buildings 42 (2010) 869–880870



The house in Morozzo was designed by Studio Roatta Architetti

Associati in Mondovı (Italy), in compliance with sustainable and

bioclimatic architecture principles, in order to obtain a very low

energy building. The overall goal was obtaining a winter heat

requirement ten times lower than the maximum allowed by the

thermal regulations in force. Such a goal was reached through

exploitation of passive solar contributions, optimisation of thermal

insulation, minimisation of uncontrolled inward air flows and use

of high efficiency plants.

The shape of the building, its orientation and the use of static

solar barriers allowed the winter solar gain to be increased (59%

contribution to the gross heat requirement) and the summer

overheating to be kept under control.

The structural system is a reinforced concrete frame partially

combined withmasonry block walls. The building is insulated with

15 cm cork slabs on the exterior facades, which leads to a thermal

transmission coefficient U = 0.22 W/m2 K. The roof is insulated

with22 cmof woodwool (U = 0.21 W/m2 K) andthe ground floor is

insulated with 10 cm of polystyrene. The total glazed surface

consists of 100 m2 of windows made of low-e coating triple glazing

(overall U = 1.1 W/m2 K). Heat is produced by an air-to-water heat

pump with a COP (coefficient of performance) of 2.54 and an

average global seasonal yield hG,s = 2.62.

The renewal of air is ensured by controlled mechanicalventilation with heat recovery having an efficiency of 75%

(T ext = 1.7 8CÀ T int = 20 8C) and the air change rate is assumed to

be 0.3 hÀ1. Fresh air is collected through a 45 m long, 100 mm

diameter, triple polyethylene pipe which is placed underneath the

garden.

With these parameters, and considering a thermostat set point

of 20 8C, the useful heat requirement is 10.38 kWh/m2. A solar

collector supplies about 95% of the yearly energy requirement for

DHW production and 50% of the energy requirement for washing.

3. Methodology: LCA in the built environment

Life Cycle Assessment (LCA) is defined as an objective

methodology to analyse and quantify the environmental con-sequences of products and services during their whole life cycle,

from extraction of raw materials, through production, use phase

and EOL, with a from-cradle-to-grave approach.

LCA is internationally acknowledged as a science-based, fairly

comprehensive and standardised environmental assessment meth-

odology and it is used in several sectors, including the building

industry, with a wide range of applications. A fairly comprehensive

review of existing LCA applications in the built environment can be

found in Sartori and Hestnes [1] and in Ortiz et al. [13].

Although the general LCA methodology is well defined, its

application in the building industry still suffers from a lack of

sector-specific standardisation. Some authors [1,3,13] in fact claim

that most existing LCAs are not comparable to a great extent, as

they are based upon different approaches and assumptions. For

this reason, the methodological choices and the results should be

presented in a transparent way.

This said, the research presented in this paper is based on the

application of LCA according to ISO standards [14,15] and following

the assumptions and conventions briefly recalled in the following

paragraphs.

3.1. System boundaries

The CEN/TC 350 ‘‘Sustainability of Construction works’’

standard (under development) recommends consideration of four

building’s life cycle stages: product stage (raw materials supply,

transport and manufacturing), construction stage (transport and

construction–installation on-site processes), use stage (mainte-

nance, repair and replacement, refurbishment, operational energy

use: heating, cooling, ventilation, hot water and lighting and

operational water use) and end-of-life stage (deconstruction,

transport, recycling/re-use and disposal).

Bearing these recommendations in mind, the system under

study was split into the phases and subsystems shown in Table 1.

Although therelativecontribution of all the stages andsubsystems

is visible in the flowchart available for downloading as an e-component, it was considered more meaningful to the research to

clearly separate the contribution of materials from energy use

during the operational phase.

3.2. Functional unit

In LCAs of whole buildings, the functional unit should be

defined so that the different buildings being compared provide the

same services, for a similar duration [2,6,13,19]. Bearing that in

mind, the function of the system under study can be defined by its

service time and by a reference area.

Consequently, the functional unit is 1 m2/year.

According to ISO 14040, ‘‘the functional unit is a measure of the

function of the studied system’’. The main function of the house iscertainly supplying a human habitation service, which can be

directly correlated to the size of the living area (heated). However,

the garage is also supplying a service, though of lower quality, and

this should also be accounted for when calculating the reference

area, which is a measure of the overall service provided. For

commercial purposes in Italy, the market value of a house is

calculated based on the sum of the living area plus 1/3 of non-

heated areas, reflecting the quality of the services provided, and

which approach was adopted in the present research (Fig. 1). This

means that the model was calculated for the whole building, over

70 years expected occupancy, and the obtained results were

divided by 70 and by 250.

Table 1Life cycle phases, subsystems and data sources.

Life cycle phase Subsystem Source of site-specific data

Pre-use and maintenance Shell and plants material Quantities estimated from building drawings and field measured data

Trans port at ion Average dist ances fr om p er sonal com munication wit h d esign er and con st ructor

Bu ilding p rocess Field m easured d at a, p ers onal com mun icat ion wit h d es igner and cons tructor,

literature [4,7,11,22,24]

Maintenance Literature [3,7,10,11,22,24,25] and personal communication with designer

and constructor

Use Energy use for heating, ventilating

and DHW

Calculated with the software application Edilclima EC501 [26]

Energy use for cooking, washing,

lighting and use of appliances

Statistical data [16,27,28]

End-of-life Dismantling, demolition,

recycling/reuse/landfill

Literature data [2,29–31] and unpublished data from Politecnico di Torino

on end-of-life of building materials

G.A. Blengini, T. Di Carlo/ Energy and Buildings 42 (2010) 869–880 871



However, some readers might think that only the heated area

should be considered as a measure of the service provided. They

can therefore adapt the value of indicators presented in this paper

multiplying by 250 m2 and dividing by 192 m2. The change of

reference area will not affect the comparison between the low

energy and the standard houses.

3.3. Data collection and modelling

As design drawings and bill of quantities were freely available

and it was possible to enter the worksite at various stages of the

building process, most of the data are site measurements.

However, a cradle-to-grave LCA cannot be made only on the

basis of directly collected data and thus site-specific data had to be

integrated with literature data, as reported in Table 1. The

inventory datasets for material fabrication, energy production

chains and transport systems were mostly extracted from the

Ecoinvent 2 database [32], while the LCI modelling was performed

using the SimaPro 7 software application [33].

3.4. End-of-life of building materials (recycling potential)

The EOL of products is an essential part of every LCA study.

However, it should be pointed out that this is probably the mostdifficult part of an LCA, as it is necessary to forecast, several years

(or decades) in advance, what a credible (or reasonable) sequence

of activities would be for dismantling and recycling (or disposing)

of construction and demolition waste (C&DW).

While it is true that there is limited quantitative informationon

the actual demolition process [22], there are a few studies [2,21,23]

that contain some quantitative and methodological information on

the role of EOL in building sustainability.

Recycling can avoid landfilling and partially displace the

environmental impacts of manufacturing, as recycled products

can substitute virgin materials, but, on the other hand, it is also

responsible for impacts related to re-processing and transporta-

tion. In such a context, it is possible that more energy is spent and

more impacts are caused through recycling than energy andimpacts saved as a consequence of avoided primary production.

LCA models, like the one here presented, should therefore be

extended over the whole recycling chain and should consider

credible and reasonable sorting yields, transportation distances,

re-processing efficiencies and take into account the quality of the

recycled products, in comparison to the correspondent virgin

products.

The present research has adopted the avoided products

approach, according to which the EOL chain is modelled

downstream, including all the activities and processes (and their

related impacts) from C&DW collection to substitution of virgin

products. The environmental burdens corresponding to

manufacturing of the substituted product are subtracted from

the system. The balance between environmental impacts and gainsin the chain (net gain) might therefore be negative, in case the

avoided impacts (benefits) are higher than the induced impacts, or

viceversa.

The ratio between the net environmental gains of the

demolition-recycling chain and the burdens corresponding to

the materials embedded in the buildingshell is called the recycling

potential [2]. The recycling potential is thus a measure of the

environmental impact reduction that can be achieved through

appropriate EOL management. The avoided product approach can

apply to both closed loop andopen loop recycling, accordingto ISO

standards [14,15].

On this point, it is worth remarking that the avoided product

convention is not always adopted. For instance, Scheuer et al. [22]

do not consider environmental credits of recycling.

In the opinion of the authors, if based on realistic processes and

efficiencies, the avoided product method is the most transparent

and it helps understanding what the benefits and drawbacks of

recycling are. In order to express an overall judgement on

sustainability, it is not in fact sufficient to state that a material

is recyclable [23], or that recyclable materials were used. In fact,

one also has to consider the forms for recycling, as well as how to

provide for disassembly, before the expression ‘‘environmentally

sustainable’’ can be used.

For these reasons, in this work, the recycling potential was

assessed and presented, but always kept separate, with an option

for exclusion, in order to enhance comparability withother studies.

3.5. Data uncertainty

The existence of uncertainties in input data and modelling is

often mentioned as a crucial drawback to a clear interpretation of

LCA results [34]. For this reason, although its use is not common

practise, uncertainty analysis is gaining importance in LCAs.

In order to understand the reliability of LCAs in the building

sector more clearly, the LCA models presented in this paper

were elaborated using data uncertainty estimations and

calculating the results not only through a deterministic

approach, but also in terms of probability distribution usingthe Monte Carlo method.

As far as the data retrieved from Ecoinvent 2 are concerned,

these are also available as probability distributions, mostly

lognormal, as described in Frischknecht and Jungbluth [35].

The definition of the uncertainty of site-specific data was much

more complicated, as they were mostly available as single

measurements or estimates.

The evaluation of the input data uncertainty was therefore

carried out according to the pedigree matrix for uncertainty

estimation described in Frischknecht and Jungbluth [35], consid-

ering the data quality management approach presented in Junnila

[20] and according to an overall data quality judgement expressed

by the participants in the research.

The input datasets presented in the next section have thereforebeen supplied with a deterministic value, as well as in terms of CV

(coefficient of variation = standard deviation/mean) and normal

distribution around the deterministic value. The Monte Carlo

simulation was run with 10,000 cycles.

3.6. Selection of environmental indicators

LCI results are commonly regarded as the most objective part of

an LCA. However, as they emerge as a long list of natural resource

use and emissions in air, water and soil, they must be converted

into understandable and meaningful indicators, before it is

possible to make any practical use of them.

Conversely, the choice of appropriate indicators and commonly

accepted methodologies to analyse inventory results is always asubjective step. This was also the case in the present research,

where the participants (designers, public administrators, research-

ers) agreed to base the overall judgement on sound, objective and

internationally recognised LCA indicators. At the same time, the

participants also recognised that there is need for comprehensive

and understandable indicators to be used in LCAs of the built

environment.

Thus, life cycle indicators were chosen to be representative of

broadly recognised areas of environmental concern, as well as

being based on international conventions, agreements, and

guidelines. This approach is consistent with the International

Standards Organization’s (ISO) recommendations for LCIA meth-

ods, which state that ‘‘the impact categories, category indicators

and characterization models should be internationally accepted,




i.e. based on an international agreement or approved by a

competent international body’’ [14].

A first group of four energy and environmental indicators was

adopted:

- Gross energy requirement (GER), as an indicator of the life cycle

total primary energy use [36];

- Non-renewable energy (NRE), as the non-renewable part of GER;

- Global warming potential (GWPf ), as an indicator of greenhouse

emissions with a time horizon of 100 years, excluding the

contribution of biogenic carbon dioxide [37];

- Global warming potential (GWPb), as an indicator of greenhouse

emissions, including the contribution of biogenic carbon dioxide;

Although GER, NRE, and GWP are sometimes regarded as

duplications of each other [24], the choice of considering all of

them was made deliberately. GER and NRE are remarkably

different in low energy houses like the one here presented, due

to the extensive use of wood. In the authors’ opinion, non-

renewable and renewable energies are both important for

mankind, while in some cases it seems that some people are not

concerned about using too much renewable energy, as it is

renewable. Low energy buildings should use low quantities of

energy, regardless of their source, and renewable energies likebiomass could reasonably be saved for other purposes.

Although global warming is closely correlated to energy use,

GWP has also been considered in order to understand whether

the decarbonation that occurs during clinker burning can

influence the results in a concrete-framed building, like the

one presented here.

Moreover, as the biogenic carbon cycle in wooden products is

often not neutral, as remarked in Peuportier [19], the influence of

biogenic carbon dioxide emissions was also investigated. Wooden

products in LCA databases are usually assigned a CO2 credit, which

includes the carbonstored in the biomass and the balance between

emissions and uptake in the wood production chain. However,

when assigning an ex ante credit to wood, one has to make sure

that the full life cycle of the biomass is considered, from forestry toEOL (either incineration, landfill or re-use), otherwise the potential

carbon sequestration could be overestimated. For this reason, a

precautionary criterion was adopted to calculate the GWPbassigning ex post the CO2 credit to re-used wood, i.e. wood that

permanently stores carbon.

In order to extend the analysis to a wider area of environmental

concern, four more indicators were selected: ozone depletion

potential (OD), acidification potential (AP), eutrophication poten-

tial (EP) and photochemical ozone creation potential (POCP) [38].

The choice of the aforementioned eight indicators corresponds,

in the ISO 14040 standard, to the selection of impact categories.

They are usually classified as mid-point (or problem oriented)

indicators and they are widely and internationally recognised as

being fairly objective indicators by LCA practitioners, as they arebased on environmental science knowledge on the effects of

different substances in the ecosystem. According to the ISO 14040

procedure, the classification step assigns items from the eco-

balance inventory (LCI) to one or more mid-point categories. The

characterization step then quantifies the contribution of the item

to the mid-point category value, for example the contribution of

NOx emissions to eutrophication.

Although ISO 14040 [14] recommends that LCAs end with a set

of mid-point environmental indicators, it should be acknowledged

that this makes the decision process more complicated, as some of

these indicators might not be concordant in identifying the best

solution. Policymakers and public administrators often express

their need for practical tools that might simplify the decision

process [39], thus several methodologies have been proposed to

convertLCI results into a narrower set of indicators or possibly into

a single score index.

Such methods are often based on theso-called damageoriented

(end-point) approach, and are aimed at evaluating the environ-

mental consequences with reference to wider areas of concern,

suchas human health, ecosystemquality, intergenerational equity,

etc. As they involve both physical andsocial aspects, with a weaker

scientific background, and they introduce subjective value choices

and uncertainty, they have collected less international consensus.

Even though single score indexes have been severely criticised

[40] and there are divergent opinions on weighting methodologies

and factors [11,12,22,30,39–41], in order to understand the

suitability of existing methodologies more clearly, and to give a

contributionto the ongoingdebate, three single score indexes have

been selected: Eco-Indicator 99 (EI99H/A), Ecological Footprint

(EF) and Environmental Priority Strategy (EPS2000) [42].

4. Description of the LCA model

Themain inventory data relevantto thelow energy house(LEH)

in Morozzo are described in the following paragraphs. A detailed

flowchart of the LCA model is available for downloading as an e-

component.

4.1. Pre-use and maintenance

Pre-use and maintenance include everything that concerns the

production of materials and plants, their transportation, the

building process and the maintenance of the building.

Before the data collection and modelling could start, the

materials were grouped into 11 shell components and 4 plants, as

reported in Table 2. The inventory dataset in Table 3 summarises

the elaboration of thefield measured data, integrated with thedata

sources reported in Table 1. The type of transportation systems and

Table 2

Components of the building shell and plants.

Shel l components Main materi als (life span: 70 years)

Basement Cement, concrete, steel bars,

concrete not reinforced, polyethylene

Garage Concrete, steel bars, concrete not

reinforced, cement, portland cement,

bricks, mortar, gravel, acrylic binder

Floors and stairs Concrete and steel bars, steel

Vertical structural elements Bricks, mortar, concrete, steel bars

Interior walls Gypsum board, steel

Roof Untreated wood, wooden roof beams,

particle board, paper, aluminium

Terrace Chromium steel, untreated wood

Wind ows and d oors Alum inium, H DPE, p art icle b oard ,

glass, steel

Surface lining Plaster, varnish, ceramic tiles

Flooring Concrete not reinforced, ceramic tiles,

stoneware, untreated woodInsulation Cork slab (external walls),

polystyrene (flooring), wood wool

(roof and interior walls)

Plants Main materials (life span: 35 years)

Water plant HDPE (drainage piping), HDPE and

aluminium (potable water pipes),

chromium steel, sanitary ceramics,

steel, glass, brass and PVC

(bathroom accessories), aluminium,

mineral wool, copper, glass

(solar panels), PVC coated

HVAC (heating, ventilating

air conditioning)

Steel, polyethylene, aluzink

(heating pump)

Lighting Copper, PVC, HDPE

Ventilating HDPE, aluzink




the distances from factories or distribution centres to the

construction site were communicated by either the contractor

or the designer. Data referring to the energy consumption and

machinery use during the building process were communicated bythe constructor: 2556 MJ of electricity and 1040 m3 of soil

excavation. Construction waste factors, i.e. cutting waste generat-

ed during the building process, and replacement factors for repair/

maintenance of the shell, finishes and plants were estimated from

the literature reported in Table 1, taking into account the

designer’s and constructor’s experience. For what it concerns

the service duration of building materials, it must be noticed that,

as reported by Kellenberger and Althaus [24], little reliable data on

the life span of building components is presently available.

Assumptions based on literature were necessary.

Fig. 2 shows an overview of grouped embodied materials.

4.2. Use phase

The energy consumption during the operational phase was

separated into uses that depend on the house size (heating and

ventilating) and the uses that depend on the number of occupants

(DHW, cooking, lighting, appliance use).

The winter heat requirement was calculated by the designers

according to the architectural and thermo-physical features, as

well as the local climate conditions. For that purpose, designers

selected the software application Edilclima EC501 [26], as they

consider it a flexible and reliable tool, which is in compliance with

legislative requirements (Decree 192/2005 subsequently amended

by legislative decree 311/2006) and the UNI EN 832 standard [43].

The energy requirement for DHW was calculated considering 4

occupants with a daily demand of 50 l. Energy used for cooking,

washing and lighting was retrieved from the official statisticsindicated in Table 1.

Table 4 summarises energy consumption for all the activities in

the operational phase. Electricity collected from thegrid is theonly

energy source, therefore the eco-profile is that relevant to the

Italian mix according to the Ecoinvent database.

4.3. End-of-life

Three distinct steps were included in the LCA model of EOL:

1. Selective dismantling of re-usable/recyclable materials and

structures (windows, steel, aluminium, roof);

2. Controlled demolition of the structural system by hydraulic

hammers and shears;

3. Operations for C&DW treatment and recycling, re-use or landfill.

Table 5 summarises the most important data describing the EOL

model, with emphasis on sortingefficienciesand destination. All the

energy consumption and environmental impacts due to transporta-tion, demolition and recycling operations were considered in the

inventory analysis, onthe basis of the results of a previous study [2].

Inventory data relevant to recycling of aluminium, steel, glass and

copper were retrieved from the Ecoinvent database, which contains

data on both productionfrom scraps (recycling) andfrom virginraw

materials (avoided products).

Fig. 2. Materials embodied in the LEH (cutting waste and replacement excluded).

Table 4

Electricity collected from the grid during the use phase.

Energy consumption (CV)

Heating and ventilating 4.7 (10%) kWh/(m2 year)

DHW 22.8 (25%) kWh/year

Cooking 542.5 (25%) kWh/year

Washing, lighting and use of appliances 1646 (25%) kWh/year

CV = coefficient of variation (standard deviation/mean).

Table 5

End-of-life of shell and plants materials.

Material Selective dismantling Controlled demolition Rubble processing

Aluminium 90% recycling – 10% recycling

Glass 90% recycling – 10% recycling (aggregate)

Steel, copper, aluzink 90% recycling – 10% recycling

Steel rebars – 70% recycling 30% recycling

Wooden roof beams 90% reuse 10% incineration –

Untreated wood 50% reuse 50% incineration –

Other wooden materials 90% incineration 10% incineration

Concrete, bricks, ceramics, plaster, mortar, stoneware – – 100% recycling (aggregate)

Others (cork, plastic, gypsum, mineral wool) 100% landfill




The lithoid fraction, i.e. concrete, mortar, bricks, ceramics, etc.,

was assumed to undergo a recycling process for the production of

secondary aggregates. This can be considered a form of open loop

recycling, as concrete and other building materials are down-

graded into recycled aggregates, therefore avoiding the production

of natural sand and gravel.

For clarity, it should be mentioned that the C&DW generated

from the building process and during maintenance operations was

considered to undergo a simplified EOL model, which involved

metal and glass separation and recycling, wood incineration and

mixed rubble recycling. EOL of cutting waste and maintenance

materials were included in the ‘‘building process’’ and ‘‘mainte-

nance’’ subsystems, respectively, in order to keep them separated

from the EOL of the house itself, as they occur at different stages.

4.4. Inventory of the standard house

The standard house (SH) mirrors the original in size features,

geographical/climatic conditions and service duration of the house

in Morozzo (Fig. 1). The energy consumption for heating was re-

calculated in compliance with the same legislative requirements

and the building shell and plants were consequently adapted.

The main differences between the SH and the LEH are those

relevant to the thickness and type of insulation, the typology andsize of the glazed surface, and the type and size of the plants, as

summarised in Table 6. In particular, the window surface was

decreased and, consequently, the external walls surface increased.

The heat pump was substituted with a natural gas boiler and the

solar collector excluded.

The inventory step was re-elaborated, taking into account the

new building features. Heating,DHW and cooking wereconsidered

to be powered by natural gas, with no solar contribution (inventory

data of the natural gas supply chain from Ecoinvent). The energy

requirement for lighting and use of appliances remained un-

changed. Due to the exclusion of the solar panel, the energy

requirement for DHW and washing was increased (Table 6). The

EOL phase remained the same as the one already described for the

LEH, although it was adapted according to the new quantities.Here it should be pointed out that one advantage of the SH, in

comparison to the LEH, was the possibility of using gas cooking

equipment. Electric cooking equipment had to be selected for the

LEH as the use of a standard natural gas device was not compatible

with legislative prescriptions due to theinsufficient aeration of the

kitchen. This penalises the LEH, as the from-cradle-to-gate natural

gas chain is more efficient than the electric chain.

5. Results and discussion

As described in the methodological section, the LCIA results are

presented at two levels:

Mid-point indicators: GER, NRE, GWPf , GWPb, OD, AP, EP, POCP; Single score end-point indicators: EI99H/A, EF, EPS2000.

5.1. Lifecycle indicators of the low energy house

Table 7 summarises the mid-point environmental indicators

relevant to the life cycle of the LEH. Pre-use and maintenance

impacts, i.e. materials-related impacts, are always higher that

those relevant to the use phase, except ozone depletion. Moreover,

EOL always shows a net environmental gain.

According to the Monte Carlo simulation, the coefficient of

variation, whichshows the range in which68% of the results fall, is

between 6 and 42% around the mean value. As far as the total life

cycle indicators are concerned, global warming and acidificationshow less disperse results, followed by energy indicators, while

stratospheric ozone, eutrophication and photochemical smog have

a higher level of uncertainty.

5.2. Contribution analysis and recycling potential

A contribution analysis was conducted to examine the role of

the subsystems highlighted in Table 1, both in terms of mid-point

and end-point indicators. As reported in Fig. 3, plants, transporta-

tion and the building process always play a minor role. The

contribution of materials in the shell plus materials used for

maintenance is usually above 50%. The use phase is dominated by

‘‘other uses’’, which have a greater impact than heating, while

cooking is remarkably lower, though not negligible, and DHW usehas virtually no relative impact.

Table 6

Inventory of the standard house.

Main changes in respect to the low energy house

Shell components

Walls Q uantity of bric ks increased (1 1 t added)

Roof OSB panel excluded

Windows Triple glass windows substituted with double glass

Total glazed surface decreased (100!35 m2)

Insulation Cork slab (walls) substituted with polystyrene of

decreased thickness (15!4cm)Polystyrene (floor) thickness reduced (10!3cm)

Wood wool (roof) substituted with polystyrene of

decreased thickness (22!5 cm)

Plants

Heating plant Heat pump substituted with natural gas boiler

(condensing)

Distribution and radiating pipelines increased

by a factor 4

Ventilating plant Excluded

Water p lant Solar panels exclu ded

Use phase

Heating H eat r eq uirement increased f rom 1 0.38 t o

109.5kWh/(m2 year) (electricity!natural gas)

Sanitary water End-use energy from 22.8 to 2960kWh/year

(electricity!natural gas)Washing End -u se energy fr om 1 50 t o 3 00 k Wh/ year

Cook in g End -u se energy fr om 5 42 .5 to 7 74 .6 k Wh /y ear

(electricity!natural gas)

Table 7

Life cycle mid-point indicators of the low energy house.

Indicators Unit Pre-use and maintenance (CV) Use (CV) End-of-life (CV) Life cycle (CV)

GER MJ 197 (23%) 134 (28%) À40 (31%) 291 (18%)

NRE MJ 132 (29%) 123 (29%) À21 (37%) 235 (20%)

GWPf kgCO2 equiv. 10.8 (20%) 7.9 (23%) À1.3 (9%) 17.4 (17%)

GWPb kgCO2 equiv. 10.8 (20%) 7.9 (23%) À2.7 (6%) 16 (18%)

OD mg CFC11 equiv. 0.77 (28%) 0.92 (34%) À0.04 (40%) 1.64 (26%)

AP mol H+ 1.20 (24%) 1.19 (24%) À0.21 (10%) 2.18 (18%)

EP g O2 equiv. 226 (34%) 112 (28%) À20 (42%) 319 (25%)

POCP g C2H4 equiv. 0.93 (29%) 0.21 (29%) À0.03 (34%) 1.12 (24%)

CV= coefficient of variation (standard deviation/mean).




What clearly emerged is that, conversely to standard buildings

and unlike the findings of other studies [1–4,6,8,19,20,22], there is

no single subsystem which overshadows the others, but the life

cycle impacts are caused by the mutual contribution of several

equally (or almost equally) important elements.

Designers and public administrators participating in the study

were surprised by the minor contribution of transportation, as it

was fearedthat the tripleglazed windows imported from Germany

and the cork slab transported over long distances by truck and by

ship might compromise the environmental performances of the

LEH. This result confirms the findings of Peuportier [19], who

estimated the contribution of transportation between 1.5 and 2.4%

of CO2 emissions.

Fig. 3 shows the important contribution of the building EOL,which corresponds to a reduction in life cycle impacts of 2–17%,

depending on the indicator. In terms of recycling potential, i.e.

comparing the net environmental saving with the environmental

burdens of the shell and plants materials, the LEH showed a

potential impact reduction of 32% in terms of GER, 17% in terms of

GWPf and 24% in terms of Eco-Indicator 99.

Therefore, an eco-efficient EOL management, as a conse-

quence of the correct choice of building materials and the proper

recycling processes, could be useful to lower life cycle impacts.

This is an interesting finding that complements previous studies

[12,21] and might influence the design of future low energy

buildings: the more energy needed during the use phase

decreases, the more important it is to pay attention to both

energy for material production and to the aspects of the

recycling potential.

It is also important to notice that the four chosen energy and

climate change indicators do not duplicate each other. In

particular, the contribution of carbon sequestered in the re-used

wood remarkably increases the recycling potential and lowers the

life cycle greenhouse emissions. There is, however, a need forfurther research in this context.

With reference to Fig. 3, it is interesting to compare analogies

and dissimilarities among the results expressed in terms of single

score indicators and mid-point indicators. For instance, EPS2000 is

the only indicatorthat assigns to the plants a remarkable role; Eco-

Indicator 99 and GER show virtually the same results; OD is the

Fig. 3. Contribution analysis of the life cycle subsystems.

Fig. 4. Contribution analysis of the embodied energy (initial + maintenance).




only indicator for which the use phase shows a contribution above

50%.

5.3. Contribution analysis: shell and plant materials

Fig. 4 shows the embodied energy of shell and plant materials.

Based on the dataset reported in Table 3, materials with similar

physical characteristics are grouped together, with exclusion of

those representing less than 1% of the GER. The results are shown

as the sum of initial non-renewable energy (including cutting

waste), plus initial renewable energy, plus maintenance (non-

renewable plus renewable).

The most important contributors to the GER of the pre-use

phase are wooden items (sawn timber, particle board, wood wool,

cork slab). However, it should be remarked that 76% is renewable

energy.

As far as GER is concerned, concrete comes after wooden

materials, but it is the first contributor to NRE, followed by bricks,steel reinforcing bars and aluminium. This confirms that even in

recently built low energy buildings, traditional materials like

concrete andsteelstill play an importantrole in terms of embodied

energy, as reported in other studies [2,44].

5.4. Scenario analysis: comparison between LEH and SH

The comparison between the life cycle impacts of the low

energy house and the standard house is probably the most

meaningful part of the research and it is helpful to highlight the

role and significance of the different subsystems in a life cycle

perspective.

Fig. 5 shows energy and climate change indicators, since they

were considered the most meaningful for the objectives of the

research, as well as the most reliable. The error bars show the

range corresponding to 68% of the results obtained after the

Monte Carlo simulation. The uncertainty assessment was run

separately for each of the selected subsystems, however itshould be said that, despite the effects of uncertainty on the

absolute accuracy of an LCA, comparative LCAs are relatively

more accurate, as uncertainty is usually highly correlated

between scenarios.

Fig. 6 shows the single score indicators obtained after the

application of the three selected weighting methodologies. In

this case, the Monte Carlo simulation was not performed, as

modelling life cycle impacts with an end-point approach

involves datasets and models that are affected by a much

higher uncertainty. This would require a deeper analysis which

is beyond the scope of this research.

As can be observed, there is an increase in the pre-use and

maintenance impacts from the SH to the LEH, though it is

relatively small.A much more evident difference between SH and LEH is that

relevant to the use phase, especially due to heating. As a

consequence, while the use phase in the SH is responsible for

more than 80% of the life cycle energy use, the contribution of

the use phase in the LEH is below 50%. It is also clear that, while

the use phase in the SH is dominated by heating, most of the

energy consumption in the LEH is related to other uses. Similar

results were also obtained for climate change and the three

single score indicators.

These findings clearly highlight the weight and significance of

the pre-use and use phases in low energy buildings, pointing out

that, when dealing with energy saving and sustainability issues,

the contribution of materials-related energy and environmental

burdens cannot be neglected.

Fig. 5. Comparison between LEH and SH (energy and climate change).




In such a context, it becomes clear that LCA canrepresent a very

interesting and powerful environmental assessment and eco-

design tool.

A further comparison between the LEH and SH has highlighted

some very interesting aspects. The winter heat requirement was

drastically reduced from 109 kWh/m2 in the SH to 10 kWh/m2 in

the LEH, which roughly corresponds to a ratio of 10 to 1 (10:1).

In a from-cradle-to-gate perspective, when considering the

overall efficiency of the heat pump/electricity or boiler/natural gas

energy chains, the ratio between the life cycle energy (GER) of SH

and LEH roughly remains unchanged (9.5:1).

As shown in Table 8, when considering the whole use phase,

therefore including DHW, cooking, lighting and use of appliances,

the above ratio changes to 3.8:1. Furthermore, when considering

the full life cycle, the ratio becomes 2.1:1 in terms of GER, 2.2:1 in

terms of GWPf and 2:1 in terms of Eco-Indicator 99.

The outstanding energy saving and environmental perfor-

mances of the studied LEH were thus confirmed after the life cycle

analysis, but to a much lower extent. This still remains a very good

result, but sensibly reduced in comparison to what was expected

by designers and public administrators.

6. Conclusions

The results of a detailed LCA applied to the house in Morozzo in

Northern Italy have highlighted that, when addressing energysaving and sustainability performances of low energy buildings,

the role and significance of all life cycle phases and subsystems

should be carefully re-considered.

On thebasis of an analysis extendedover a 70 years lifetime,the

dramatic contribution of materials-related impacts has emerged.

Shell materials have the highest relative contribution, but

maintenance operations also play a major role, although it should

be noticed that there is still need for more reliable data on the

actual service duration of several materials. The contribution of

plants, building process and transportation is minor, though not

always negligible.

Unlike standard buildings, where heating and ventilating

overshadow both the rest of the operational energy and the whole

life cycle,in the LEH theuse phaseis dominated by ‘‘other uses’’, i.e.lighting, electric appliances, cooking and DHW. Here it must be

said that heat energy requirement was calculated with a

simulation tool and could not fully take into account the high

uncertainty related to people’s living habits. Therefore it would be

interesting after a few years to compare simulated data with field

measurements.

The role of recycling potential, as an effective tool to decrease

life cycle impacts, though postponed in the future, has also been

quantified.

Hence, as far as the changing role of life cycle phases and

subsystems in low energy buildings is concerned, it can be stated

that there is not one single item or aspect that dominates the life

cycle impacts, but several of them are equally important in

determining the overall sustainability.As energy saving is pushed towards the upper limit, the use of a

single electric appliance, whose influence can be neglected in the

case of a standard building, might become important.

The changing role of life cycle subsystems and their increased

inter-dependency fully justify the application of LCA.

As a major conclusion of the research, the overall goal of

environmental sustainability behind the construction of the house

in Morozzo has been proved to be compatible with the life cycle

approach, although applied ex post. The higher embodied burdens

were compensated by the remarkable operational energy saving.

However, the LCA has shown that while the winter heat

requirement was reduced by a ratio of 10:1, the life cycle energy

was only reduced by 2.1:1 and the life cycle impacts were only

reduced by 2.5:1–1.6:1, depending on the indicator.

Fig. 6. Comparison between LEH and SH (end-point indicators).

Table 8

Comparison between life cycle indicators (SH:LEH ratio).

Use (heat) Use (total) Life cycle

GER 9.5:1 3.8:1 2.1:1

NRE 10.4:1 4.1:1 2.5:1

GWPf 9.4:1 3.8:1 2.2:1

GWPb 9.4:1 3.8:1 2.3:1

EI99H/A 10.0:1 4.0:1 2.0:1

EF 7.9:1 3.2:1 1.7:1

EPS2000 9.1:1 3.6:1 1.6:1




These results necessarily reflect the complex combination of

the case study building unique features, the locally adopted

construction techniques, the behavioural pattern of Italian citizens,

site-specific climate conditions, local regulations and the Italian

energy mix. Therefore the results should not be generalised,

although some general remarks can certainly be given.

These findings emphasise the need for systematically verifying

the environmental performance of future low energy building

using a holistic approach, as single improvements might not be

effective in a life cycle perspective, and could even disappoint

expectations.

Energy and environmental certification schemes, in Italy and

elsewhere, wouldcertainly benefit from the adoption of a life cycle

approach, but it should be kept in mind that excessive simplifica-

tions, generalisations and blind reliance on user-friendly tools and

non-transparent databases still remain a real threat to genuine

sustainable development.

Acknowledgements

The authors wouldlike to thank Studio Roatta Architetti Associati

in Mondovı for the data and information supplied, the staff of

Regione Piemonte for the support, Msc. Agnese Fiorenza for her

help in the data collection and elaboration.

Appendix A. Supplementary data

Supplementary data associated with this article can be found, in

the online version, at doi:10.1016/j.enbuild.2009.12.009.

References

[1] I.Sartori,A.G. Hestnes, Energy usein thelifecycleof conventional andlow-energybuildings: a review article, Energy and Buildings 39 (2007) 249–257.

[2] G.A. Blengini, Life cycle of buildings, demolition and recycling potential: a casestudy in Turin-Italy, Building and Environment 44 (2009) 319–330.

[3] O. Ortiz, C. Bonnet, J.C. Bruno, F. Castells, Sustainability based on LCM of residen-tial dwellings: a case study in Catalonia, Spain, Building and Environment 44

(2009) 584–594.[4] S. Blanchard, P. Reppe, LCA of a Residential Home in Michigan, School of NaturalResources and Environment, University of Michigan, Michigan, 1998, p. 60.

[5] C. Thormark, Environmental analysis of a building withreused building materials,International Journal of Low Energy and Sustainable Buildings 1 (2000).

[6] K. Adalberth,A. Almgren, E.H.Petersen, Life CycleAssessment of fourmulti-familybuildings,International Journal of Low Energyand SustainableBuildings2 (2001).

[7] T.Y.Chen, J. Burnett, C.K. Chau, Analysisof embodied energy use in the residentialbuilding of Hong Kong, Energy 26 (4) (2001) 323–340.

[8] B. Maddox, L. Nunn, Life Cycle Analysis of Clay Brick Housing Based on a TypicalProject Home, The Centre for Sustainable Technology, University of NewCastle,NewCastle, 2003, p. 34.

[9] M. Erlandsson, M. Borgb, Generic LCA-methodology applicable for buildings,constructions and operation services: today practice and development needs,Building and Environment 38 (2003) 919–938.

[10] N. Mithraratne, B. Vale, Life cycle analysis model for New Zealand houses,Building and Environment 39 (2004) 483–492.

[11] S. Citherlet, T. Defaux, Energy and environmental comparison of three variants of a family house during its whole life span, Building and Environment 42 (2007)

591–598.[12] N. Huberman, D. Pearlmutter, A life-cycle energy analysis of building materials in

the Negev desert, Energy and Buildings 40 (2008) 837–848.[13] O. Ortiz, F. Castells, G. Sonnemann, Sustainability in the construction industry: a

review of recentdevelopments basedon LCA,Construction andBuildingMaterials23 (2009) 28–39.

[14] ISO 14040, Environmental Management–Life Cycle Assessment—Principles andFramework, InternationalOrganizationfor Standardization,Geneva, Switzerland,2006.

[15] ISO 14044, Environmental Management–Life Cycle Assessment—Requirementsand Guidelines, International Organization for Standardization, Geneva, Switzer-land, 2006.

[16] ENEA, Rapporto Energia e Ambiente 2007, ENEA, Rome, Italy, 2008.[17] J.B. Guinee, Handbook on Life Cycle Assessment—Operational Guide to the ISO

Standards, Kluwer Academic Publishers, Dordrecht, 2002.[18] SETAC, Guidelines for Life-Cycle Assessment: A ‘‘Code of Practice’’, Society of

Environmental Toxicology and Chemistry (SETAC), 1993.[19] B.L.P. Peuportier, Life cycle assessment applied to the comparative evaluation of

single family houses in the French context, Energy and Buildings 33 (2001) 443–450.

[20] S. Junnila, Life cycle assessment of environmentallysignificant aspectsof an officebuilding, Nordic Journal of Surveying and Real Estate Research 2 (2004) (SpecialSeries).

[21] C. Thormark, A low energy building in a life cycle-its embodied energy, energyneed for operation and recycling potential, Building and Environment 37 (2002)429–435.

[22] C. Scheuer, G.A. Keoleian, P. Reppe, Life cycle energy and environmental perfor-mance of a new university building: modeling challenges and design implica-tions, Energy and Buildings 35 (2003) 1049–1064.

[23] C. Thormark, The effect of material choice on the total energy need andrecycling potential of a building, Building and Environment 41 (2006)1019–1026.

[24] D. Kellenberger, H.G. Althaus, Relevance of simplifications in LCA of buildingcomponents, Building and Environment 44 (2009) 818–825.

[25] C. Matasci, Life cycle assessment of 21 buildings: analysis of the different lifephases and highlighting of the main causes of their impact on the environment,in: Memoire N. 128/2006, Master en Sciences Naturelles de l’EnvironnementUniv. de Geneve, ETH Zurich, Zurich, 2006.

[26] EDILCLIMA EC501—Edificio Invernale (L. 10/91) vers. 6, Available from: http://

www.edilclima.it.[27] Piano Energetico della Provincia di Torino, 1997, Available from: http://www.

provincia.torino.it.[28] MICENE, Misure deiconsumi di energia elettrica in 110 abitazioni italiane—eERG,

End-use Efficiency Research Group, Dipartimento di Energetica, Politecnico diMilano, Milan, 2004.

[29] APAT, I rifiuti da costruzione e demolizione, Rome, 2005, Available from: http://www.apat.it.

[30] G.A. Blengini, E. Garbarino, Sustainable constructions: ecoprofiles of primary andrecycled building materials, in: Proceedings of the International SymposiumMining Planning and Equipment Selection MPES2006, Turin, Italy, (2006), pp.765–770.

[31] L. Brimacombe,P. Shonfield, Sustainability and SteelRecycling, International Ironand Steel Institute, 2001.

[32] ECOINVENT, Life Cycle Inventories of Production Systems, Swiss Centre for LifeCycle Inventories, 2007 Available from: http://www.ecoinvent.ch.

[33] SimaPro 7.2, Software and Database Manual, Pre’ Consultants BV, Amersfoort,The Netherlands, 2008.

[34] G.W. Sonnemann,M. Schumacher, F.Castells,Uncertaintyassessment by a Monte

Carlo simulation in a life cycle inventory of electricity produced by a wasteincinerator, Journal of Cleaner Production 11 (2003) 279–292.

[35] R. Frischknecht, N. Jungbluth, Overview and Methodology Data v2.0 (2007),Ecoinvent Report No. 1, 2007, Available from: http://www.pre.nl/ecoinvent.

[36] I. Boustead, G.F. Hancock, Handbook of Industrial Energy Analysis, Chichester/ John Wiley, New York, 1979.

[37] IPCC, Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories,1996.

[38] SEMC, MSR 1999:2—Requirements for Environmental Product Declarations,Swedish Environmental Management Council, 2000 Available from: http://www.environdec.com.

[39] D.A. Georgakellos, The use of the LCA polygon framework in waste management,Management of Environmental Quality: An International Journal 17 (2006) 490–507.

[40] I. Boustead, B.R. Yaros, S. Papasavva, Eco-Labels and Eco-Indices—Do They MakeSense? Paper Number: 00TLCC-49, Society of Automotive Engineers Inc., 2000Available from: http://www.boustead-consulting.co.uk.

[41] B. Lopez Mesa, A. Pitarch, A. Tomas, T. Gallego, Comparison of environmental

impacts of building structures with in situ cast floors and with precast concretefloors, Building and Environment 44 (2009) 699–712.[42] R. Frischknecht, N. Jungbluth, Implementation of Life Cycle Impact Assessment

Methods, Data v2.0 (2007), Ecoinvent report No.3, 2007, Available from: http://www.pre.nl/ecoinvent.

[43] UNI EN 832, Thermal Performance of Buildings—Calculation of Energy Use forHeating, Residential Buildings, CEN European Bureau for Standardisation, 2001.

[44] M. Asif, T. Muneer, R. Kelley, Life cycle assessment: a case study of a dwellinghome in Scotland, Building and Environment 42 (2007) 1391–1394.



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