1. Building a sustainable future with Life Cycle Assessment (LCA)

In the current context of climate emergency and the transition to a low-carbon economy, the construction sector plays a pivotal role in reducing environmental impacts and improving resource efficiency. Life Cycle Assessment (LCA) has become a key technical tool for evaluating the environmental impacts associated with all stages of a building’s life cycle, from resource extraction and construction (A1-A4), through its use, maintenance, and repair (B1-B4), to its end of life, demolition, and waste management (C1-C4). The goal is to assess the total emissions, expressed in terms of carbon equivalent (CO2eq).

This holistic approach enables the identification of opportunities for improvement in design, material selection, and construction solutions, especially during the early stages of the project, when there is still significant room for decision-making.

On the other hand, Life Cycle Costing (LCC) allows the evaluation of a building’s costs over its entire life cycle, from construction to end-of-life. When combined with LCA, it provides a comprehensive perspective for making informed decisions that balance environmental impact with economic profitability. This integrative approach is increasingly necessary to comply with European regulations such as the Energy Performance of Buildings Directive (EPBD 2024) and to access sustainable financing according to the EU Taxonomy.

2. Aiguasol’s expertise: leading the way in LCA and LCC for sustainable design

Carrying out this type of study in the early stages of a project provides crucial information for decision-making regarding materials, construction systems, energy systems, and the need for renewable energy production, with the goal of reducing impact and thus achieving more sustainable and environmentally friendly projects.

At Aiguasol, various methodologies are employed depending on the project phase and client needs:

2.1 Aiguasol’s Internal Life Cycle Assessment Tool

Aiguasol has developed an internal tool suitable for the early stages of a project when the project definition is not yet complete. This tool uses the One Click LCA software database and, on the one hand, provides the possibility of obtaining a complete initial LCA from basic measurements. On the other hand, it allows the comparison of different construction systems or materials to visualize the impact differences between them and their implications for the overall building, enabling decisions to reduce impact.

2.2 Carbon Designer

This One Click LCA software application allows the creation of reference buildings based on the building’s shape, measurements, scope, structural type, usage, and location. The result can be very useful for comparison and for identifying critical points. It is also a good option when a complete LCA is required, even when the project is not fully defined. Carbon Designer allows the integration of other studies, such as the incorporation of installations or finishes.

2.3 One Click LCA

The use of the One Click LCA software is intended for the final stage of the executive project and the end of construction, where final measurements and information about selected materials are available. Having a definitive version of the life cycle analysis allows the impact of the ongoing construction to be understood, highlighting the process carried out by the design team in previous phases and also facilitating the attainment of points in environmental certifications.

2.4 Aiguasol’s Internal LCC Tool

Aiguasol has developed an internal tool that evaluates life cycle costs in building decarbonization projects (investment, operation and maintenance costs, replacement, etc.), enabling decision-making in terms of investment with a life cycle perspective. This tool is complemented by a module that calculates operational emissions and the internal LCA tool. The detailed calculation of embodied carbon and costs throughout the life cycle allows multi-parameter analysis (from different perspectives), facilitating the final selection of an optimal cost and/or environmentally optimal scenario.

3. Success stories

Aiguasol’s experience in applying LCA and LCC covers a wide variety of building typologies and intervention scenarios, from comprehensive building studies, to the analysis and comparison of specific construction solutions, to feasibility studies for energy systems and renewable energy production. This applied knowledge allows the analysis level to be adapted to the real needs of each project and client, optimizing both environmental impact and economic feasibility.

3.1 Comprehensive building studies

Aiguasol has conducted integrated LCA studies in new building projects aiming to optimize environmental performance from the design stage. A notable example is the “Infinito Delicias” building, the headquarters of the Daniel and Nina Carasso Foundation in Madrid.

At Infinito Delicias, the LCA study was present from the basic project phase. The initial analyses focused on comparing materials in terms of embodied carbon and their biogenic content, prioritizing low-impact materials, especially for construction systems that made up a larger portion of the building. Without the goal of obtaining a complete building result in this phase, the main decisions regarding material selection included maximizing the use of organic materials such as wood, using biodegradable cork insulation, reusing 95% of the existing structure, and employing recycled materials. In the executive phase, the first complete LCA was carried out using One Click LCA, assessing the rehabilitation of the building against new construction. During construction, modifications were made based on the actual work process, and results were also obtained for fresh water use and ozone depletion. This analysis allowed the design team to adopt materials and construction solutions with lower environmental impact, contributing to the project’s sustainability objectives. The rehabilitation reduced embodied carbon by 50% compared to a traditional design.

Infinito Delicias won the Holcim Gold Europe Award in 2023 for reusing much of its structure and selecting regenerative materials.

Another key project within Aiguasol’s LCA work is the environmental impact study of materials for a medical center in Cardiff, where the work focused on Stage 3 and Stage 4. The first phase was an advanced basic stage, and although many decisions had been made, the design team was open to making modifications to improve the result. In this initial phase, the study focused on the building’s structure, a critical element in this case, analyzing different scenarios to optimize it in various sections of the building. One case study involved examining different slab thicknesses and reinforcement, foundation types, or beam separation based on their size. In a project where reinforced concrete material was firmly established, the focus was on optimizing it by reducing material volume. With defined scenarios, the complete LCA was carried out at the end of Stage 3 and continued through Stage 4, with various deliverables as the measurements and material definitions solidified.

3.2 Concrete solution studies

LCA has also been successfully applied to specific interventions in existing buildings. As part of the European Green Deal ARV project in collaboration with the IREC (Institute for Energy Research of Catalonia), Aiguasol carried out the LCA for the iconic GESA building in Palma de Mallorca, focusing on the rehabilitation of the façade and the integration of sustainable energy systems, such as building-integrated photovoltaics (BIPV). The study considers three renovation scenarios: a conventional option, an optimized one, and one incorporating BIPV. Over a 50-year time horizon, the environmental impact of each alternative was evaluated, quantitatively demonstrating the potential of decarbonization strategies in existing buildings. Simultaneously, LCC was applied to assess the economic value of renovating the ventilation systems, ensuring long-term investment efficiency by balancing environmental and economic criteria.

Other examples include the PLUG-N-HARVEST, project, which analyzed modular prefabricated solutions for the energy retrofit of buildings, and various studies on public buildings, such as police stations in Catalonia.

3.3 Comparison of Construction Elements

In the early design stages, LCA can be especially useful for guiding strategic decisions before concrete solutions are defined. This approach has been applied in various international projects, such as Shusha, King Salman Park, NEOM, and Trojena (2021), where Aiguasol conducted life cycle analysis studies using the previously mentioned tool, offering environmental impact comparisons between different construction solutions and materials, as well as LCA results for complete buildings based on simple measurements. This service allows the establishment of objective sustainability criteria from the outset of the project, anticipating compliance with regulations or environmental certification in demanding contexts.

3.4 Comparisons of Energy Systems – Thermal and Renewable Electricity Production

In decarbonization projects, the LCC tool has been used to study the economic impact of different generation, distribution, storage, and thermal emission solutions (aerothermal, geothermal, etc.), to assess the optimal cost system for decarbonizing large commercial buildings. The combination of thermal generation and renewable electricity production scenarios is complex, and for this reason, the tool has worked not only on Life Cycle Costs but also on the LCOE (Levelized Cost of Energy) to dimension and select a final scenario that achieves minimal CO2 emissions and cost over the life cycle.

These analyses started with large-scale projects involving high-consuming buildings. However, the standardization of tools and the expansion of the database from project to project have allowed for the optimization of a methodology and working process that can be applied to all types of buildings and projects.

4. The future of LCA: overcoming challenges and seizing opportunities for change

Life Cycle Assessment is gaining prominence in the construction sector as an indispensable tool for understanding and reducing the real environmental impact of buildings. However, despite its potential, its application remains partial, uneven, and often limited to regulatory compliance or voluntary certifications, without full integration into design processes or strategic decision-making. It is often reduced to a final exercise, after materials and systems have already been defined, losing much of its transformative potential.

From a critical perspective, it must be acknowledged that LCA is being applied, but not always correctly. To have a real impact, it must be part of the early stages of the project and aligned with client priorities, regulatory requirements, and long-term decarbonization objectives. Moreover, improvements in data quality, tool accessibility, and the training of involved stakeholders are needed.

Regarding its incorporation into certification schemes, it is clear that LCA should be a central pillar in evaluating the sustainability of a building, at the same level as operational energy efficiency. While certifications such as LEED, BREEAM, or DGNB already include LCA criteria, its application is still optional or not adequately weighted. The mandatory integration of LCA in the revised EPBD (2024) and other European directives marks a paradigm shift that should extend to all certification tools, both public and private, to ensure a comprehensive life cycle evaluation.

In conclusion, LCA should not just be a technical tool, but a mindset shift in how buildings are designed, constructed, and valued. This will only be possible if it is consolidated as a regulatory, educational, and cultural requirement in the sector.