=Paper=
{{Paper
|id=Vol-3812/paper3
|storemode=property
|title=Prospective and retrospective approaches to integrate life cycle assessment in configurators: A multiple case study in the construction industry
|pdfUrl=https://ceur-ws.org/Vol-3812/paper3.pdf
|volume=Vol-3812
|authors=Irene Campo Gay,Lars Hvam,Johan Ernfors
|dblpUrl=https://dblp.org/rec/conf/confws/GayHE24
}}
==Prospective and retrospective approaches to integrate life cycle assessment in configurators: A multiple case study in the construction industry==
https://ceur-ws.org/Vol-3812/paper3.pdf
⋆
Irene Campo Gay1*, Lars Hvam11 and Johan Ernfors2
1
Technical University of Denmark, Anker Engelunds Vej 101 2800 Kongens Lyngby, Denmark
2
MOKO AB, Humlegårdsgatan 14 114 46 Stockholm, Sweden
Abstract
This study contributes to the evolving dialog on sustainable practices, emphasizing the strategic
integration of life cycle assessment (LCA) in configurators to comply with new regulatory standards
and achieve environmental objectives. We investigated the application of configurators integrating
LCA through a comparative analysis of two case studies in the construction industry: a prospective
approach applied during the early design stages, and a retrospective approach using post-design. Our
findings illustrate that prospective LCA configurators can significantly influence early design choices
and facilitate preliminary environmental impact assessment. Conversely, a retrospective LCA
configuration approach offers more precise and accurate assessments based on finalized designs,
enabling detailed LCA reporting and saving significant time and effort. The analysis underscores that
the application of these approaches is not mutually exclusive. This suggests that a combined strategy
could maximize the potential of these tools. Such a combination would facilitate a more dynamic
interaction between the early and later design stages, ensuring that the environmental assessment is
thorough and iterative. Additionally, it would help the company gain in-depth insights into the
environmental aspects of the design process.
Keywords
configurators, construction, environmental impact, life cycle assessment (LCA), sustainability 1
1. Introduction product customization [4]. They allow users to select
from various options and configurations of a product,
Sustainability is widely recognized as a multifaceted automatically adjusting components and features
concept encompassing three dimensions: according to user choices. This technology enhances the
environmental, social, and economic. Notably, the decision-making process by providing immediate
environmental dimension plays a foundational role feedback on potential configurations, thereby
given its direct influence on socioeconomic elements [1]. significantly improving speed, quality, and efficiency
In assessing environmental impact, particular attention [5].
has been given to the environmental impact of products Additionally, configurators enhance efficiency by
and services. One of the most widespread methodologies automating the creation of crucial documents, such as
for assessing environmental impact is life cycle quotes and bills of materials. This automation ensures
assessment (LCA) [2]. accuracy and consistency in documentation; it is
In this context, the European Commission has particularly valuable in complex configurations, where
highlighted the urgency of making sustainable products manual processes are prone to errors [6].
the norm across Europe by setting stricter product The integration of LCA with configurator
design and lifecycle standards [3]. As a result, the technology is quite promising for enhancing sustainable
increasing focus on assessing environmental product development. By embedding environmental
performance is evidence of the clear need for digital assessment capabilities in configurators, companies can
tools to support this process. provide real-time data on the environmental impacts of
Configurators are a widespread technology that various product options. This integration can facilitate a
emerged in the late 1970s as decision support systems more informed design, incorporating environmental
designed to streamline the specification process during consequences alongside traditional factors, such as
ConfWS '24: 26th International Workshop on Configuration, Sep 2–3, © 2023 Copyright for this paper by its authors. Use permitted under
Creative Commons License Attribution 4.0 International (CC BY 4.0).
2024, Girona, Spain
∗
Corresponding author.
ircag@dtu.dk (I. Campo Gay)
0000-0002-8962-5386 (I. Campo Gay); 0000-0002-7617-2971 (L.
Hvam)
CEUR
ceur-ws.org
Workshop ISSN 1613-0073
Proceedings
pricing. Furthermore, configurators can enhance the helps to understand and improve the environmental
communication of environmental assessment results, a performance of current technologies [20, 21].
crucial aspect of LCA [7]. On the other hand, prospective LCA evaluates the
Despite the significant potential of this technology, potential environmental impacts of products before they
research on the integration of LCA into configurators is are implemented. It is used to guide decision-making
still in its early stages. However, over the last five years, during the development phase by predicting future
this topic has increasingly captured academic interest, as impacts [20, 21].
reflected in numerous recent publications [8–19].
Moreover, no research has examined the different 2.2. Configurators and sustainability
implications of LCA in either a prospective or
The increasing focus on environmental considerations
retrospective manner within the context of
in the use of configurators has become a significant area
configurators. This gap in the literature leads to the
of interest over the past five years. This trend is
following research question:
noticeable in the academic community and across
RQ: What are the implications of a proactive and
various industries. For instance, standard product
retrospective of life cycle assessment through
configuration software applications such as Tacton CPQ
configurators?
are developing their environmental impact assessment
We examined two different case studies of
capabilities by incorporating LCA features into their
companies that have successfully developed
applications [22].
configurators with LCA. The first case study involved
Various researchers have also turned their attention
using this technology during the early design phase to
to this subject in the academic sector. Given the novelty
evaluate various design alternatives. The second case
of the topic, the range of issues discussed in these studies
study described how a configurator, used over finalized
regarding the integration of LCA and configurators is
designs, enables precise and accurate LCA. Both case
quite diverse, demonstrating the broad scope of the field.
studies pertain to the same sector: the construction
Hankammer et al. [13] extensively reviewed over
industry.
900 configurators, providing valuable insights into
We explored these case studies to assess and
enhancing sustainability features across sectors.
compare their impacts, thereby contributing to the
Responding to the need for streamlined LCA
research community’s understanding of how
assessments, Spreafico et al. [8] introduced I-Tree, a tool
configurators can be effectively employed to improve
that leverages real-time data for efficient eco-
environmental development.
assessment. Similarly, Rousseau et al. [10] explored the
The structure of this paper is as follows. In Section
impact of environmental indicators in configurators,
2, we present the theoretical background of LCA
focusing mainly on sustainability enhancement in 3D
typologies in terms of application timing. and we review
printing.
the academic research conducted on configurators,
To address the nexus between product variety and
integrating LCA considerations. In Section 3, we
sustainability, Medini et al. [9] proposed a
describe the methodology used for analyzing the
comprehensive framework, while Wiezorek and
comparative case studies, and we introduce both case
Christensen [14] focused on refining configurator
studies. In Section 4, we present the findings from the
architectures to enable better sustainability data
analysis, and in Section 5, we discuss the implications of
communication. In consumer electronics, Hankammer
the results. Finally, in Section 6, we summarize the key
et al. [11] found that default sustainable options
conclusions.
significantly influence consumption patterns. Campo
Gay et al. [18] analyzed the successful integration of
2. Theoretical background LCA into configurators, guiding users toward
2.1. Prospective and retrospective LCA sustainable choices. Focusing on sustainability
integration, Christensen and Wiezorek [12] aligned
The use of LCA is subject to different contexts and can configurators with ISO 14040 standards, while Campo
be driven by distinct aims and goals. In terms of the time Gay and Hvam [17] demonstrated the transformative
perspective, LCA can be divided into two primary impact of sustainability-focused configurators,
categories [20, 21]. On the one hand, retrospective LCA particularly in construction.
is aimed at assessing the effects of something that Regarding configurators’ development, Piroozfar et
occurred; on the other hand, prospective LCA is a al. [16] discussed solutions tracking environmental
forward-looking approach [20, 21]. impact, while Helo et al. [15] introduced software
Retrospective LCA evaluates the environmental streamlining environmental assessments in supply
impacts of existing products based on actual data. It chains. Moreover, Jakobsen et al.’s [19] call to redesign
product configuration systems for better sustainability
integration tied these efforts together, portraying a For the company described in the second case, we
concerted push toward deeper sustainability began with an initial semistructured interview based on
considerations in configuration processes across sectors. the main research question. This was followed by six
All of these efforts highlight a strong trend toward semistructured interviews to understand the company’s
deepening sustainability considerations within working processes and configuration systems. We
configuration processes. finalized our analysis with a review of the results by one
of the main configurator developers at the company.
3. Methods
3.2. Case company 1
Given that the advancement of configurators
incorporating LCA is still at an early stage, elucidating The company is a subsidiary of a large international
their full potential and application is a notable challenge. corporation that operates in Sweden and has
To address this gap, we conducted a qualitative case approximately 350 employees. It specializes in
study analysis comparing two distinct applications of developing, manufacturing, and marketing cement for
configurator systems within the construction industry. infrastructure, such as roads, tunnels, bridges, and
Our objective was to delve deeply into their utilization residential, commercial, and industrial buildings.
of LCA and compare their effectiveness to gain in-depth Recognizing the upcoming regulations that will take
insights. effect in 2025, which impose limitations on new
As highlighted by previous research [23,24], case construction projects, the company saw the need for an
studies are essential for understanding the key variables, early design tool to assist in this process. They
the connections between them, and the reasons behind developed an LCA configuration to facilitate and
these relationships. promote environmentally friendly design options in the
We identified two case companies using initial stages of projects when decisions are more
configurators for environmental impact assessment, flexible and have fewer resource implications. This tool
employing standard LCA methodology. These assists users in the educational process, encouraging the
companies operate within the construction sector in consideration of less conventional options and more
Sweden. environmentally sustainable solutions.
The main reasons are first, that, according to the Given the high level of uncertainty in decision-
United Nations Environment Programme (UNEP), the making during the early design phase of projects, a
building and construction industry stands as the most preliminary LCA was performed. In addition to serving
polluting industry sector, responsible for 38% of all as a decision support tool to address the complexity of
energy-related CO2 -eq emissions [25]. Consequently, environmental and technical requirements, the tool was
the construction sector has played a pioneering role in modeled to quantify LCA to determine the margin of
shaping standards and regulations, as exemplified by the safety concerning maximum statutory limits.
European standard EN 15804 for environmental product The company has collaborated with external
declarations [26], aligned with international LCA consultants over the past four years to develop this tool,
methodology standards ISO 14040 and ISO 14044 [7,27]. reaching the final testing phase in the first quarter of
Second, Sweden has been a leading country in terms 2024. Ownership of the tool was transferred to the
of introducing new policies and regulations for the company during the second quarter of 2024, with full
construction sector. Currently, it is compulsory to integration into the company’s workflow scheduled for
declare an LCA on new buildings, and beginning in 2025, completion by June 2024.
new projects must adhere to statutory limits on CO2-eq
emission per m2 per year across the life cycle [28]. 3.3. Case company 2
Consequently, all these factors motivate the The company is a small enterprise that has been based
construction sector in Sweden to seek out new tools and in Sweden since 2018 and employs 35 people. It
solutions to support their initiatives and make the specializes in designing and planning the construction
studied companies ideal case studies. aspects of projects. The company uses a configuration
system approach to streamline its building design
3.1. Data gathering process, which optimizes the overall process.
To analyze the first case company, we conducted a series In response to new regulations requiring LCA
of systematic observations of the configuration process. declarations for construction projects since 2022, the
We evaluated the experiences of the primary company has integrated LCA evaluation into its
configurator implementor involved in the project over a established configurators. To facilitate this, the company
period of four years. uses a commercial solution named One Click LCA, a
leading cloud-based software solution for
Table 1 Table 2
Company Case 1: Early Design Stage Configurator Company Case 2: Post-Design Specification of
Usage (Prospective) Configurator Usage (Retrospective)
Aspect Description Aspect Description
Stage of use Used in the very early design Stage of use Used after the building design
stages for planning is finalized
Main purpose of the To make environmentally Main purpose of To create detailed LCA reports
LCA integration conscious decisions and the LCA
compare different solutions integration
LCA approach Prospective, integrating LCA LCA Approach Retrospective, LCA applied to
from the start of a design finalized designs
Output Overview of environmental Output Detailed environmental impact
impacts and technical reports based on specific
aspects materials used and their
Required Preliminary technical quantities
configuration inputs requirements and Required High-level drawing
environmental priorities configuration specifications
LCA integration During the configuration. input
kind with the LCA integration After configuration, based on
configurator kind with the the automatic generation of
Impact on the Significant influence over configurator specifications (i.e., a part list
design process the design approach with quantities), the LCA is
Environmental Screening LCA, preliminary performed through an external
focus impact assessments tool (One Click LCA).
Suitability for New projects with undefined Impact on the No or minimal impact on the
Projects design parameters design process design.
creating Environmental Product Declarations (EPDs) Environmental Detailed LCA, focusing on the
and LCA reports for building materials and products. Focus quantifiable impacts of
Consequently, the company has updated its materials
configuration system to automatically generate a Suitability for Projects with set designs
comprehensive material list with detailed material Projects needing LCA reflection
quantities in kilograms. These data can then be In contrast, Table 2 presents the case of Company 2,
seamlessly processed by One Click LCA and integrated where the application is used after the design has been
into the company’s database to produce comprehensive finalized, adhering to a retrospective approach.
EPDs. Subsequently, we examined the implications of
choosing either a prospective or a retrospective
4. Results approach to how a new company’s resources, design
process, and overall strategy for sustainability are
First, we characterized how each application on the impacted. This should help in understanding the
configurator integrating LCA capabilities works and strategic differences between these two approaches.
impacts the building design process, focusing on when Table 3 outlines the considerations for a prospective
they are used, what outputs they produce, and their approach, whereas Table 4 details the considerations for
ultimate influence on design decisions and a retrospective approach when LCA is integrated into
environmental assessments. configurators. It is important to note that retrospective
Table 1 illustrates the case of Company 1. The design is considered viable only for companies that
application is employed during the early design stage of have already implemented configurators. Implementing
the building process, representing a prospective a retrospective approach without pre-existing
approach. configurators would be significantly costly and
inefficient.
Table 3 Table 4
Considerations for a Prospective Approach to Considerations for a Retrospective Approach to
Configurators Integrating LCA Configurators Integrating LCA
Feature Evaluation Explanation Feature Evaluation Explanation
Iterative Yes Facilitates Iterative No The LCA
design iterative design design evaluation occurs
adjustments once the
during early configuration is
stages finalized
Approach to Prospective Used to influence Approach to Retrospective Used after design
design initial design design choices are made
choices and Accuracy High Calculations are
integrate LCA detailed, based on
Accuracy Low Estimates are precise
broad and based information
on preliminary Influence in None or The LCA is
data design minimal carried out to
Influence in High Can significantly reflect on the
design alter design design rather
outcomes than modify it
LCA is the Yes The primary aim LCA is the No LCA is secondary
main aim of is to guide main aim of and happens
the environmentally the thanks to the
configurator conscious design configurator configuration
Further No Standalone use Further Yes Requires
integrations for initial design integrations integration with
stages One Click LCA
Resource High Requires the Resource Low Utilizes existing
investment in development of a investment in configurator
developing the LCA focused developing
configurator configurator the
Cost Medium/High Licenses and configurator
running cost of Cost Medium/High While the
configurator tool configurator is in
place, there are
costs for licenses
on external LCA
databases.
5. Discussion practices. We explored the use of configurators
integrating LCA at different stages of the design process
A prospective approach in configurators integrating through two contrasting case studies, a prospective and
LCA allows for the early detection and mitigation of a retrospective LCA approach in the construction
environmental impacts. In contrast, a retrospective industry.
approach ensures that these mitigations are based on By employing prospective and retrospective LCA
precise, real-world data, ultimately enhancing the tools, companies can achieve a more thorough
accuracy and reliability of environmental assessments. understanding of environmental impacts at different
Despite the benefits of a prospective configurator project stages, leading to more informed decision-
integrating LCA, the higher cost and resource making. This approach not only aids in achieving
requirements associated with developing and compliance with evolving regulatory standards but also
maintaining configurators must be considered. The aligns with broader corporate sustainability goals.
investment in licenses and running costs of Future research should continue to explore the
configuration applications can be substantial, but the development and application of these tools across
long-term benefits of reduced environmental impacts different sectors to fully realize their potential in driving
and alignment with policies and requirements can sustainable development.
compensate for initial costs.
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