# Impact of climate change on the corrosion of the European reinforced concrete building stock

Silvia Dimova, Cristina Silvia Polo Lopez, Maria Luisa Sousa, Guido Rianna, Emilio Bastidas-Arteaga, Maria Nogal, Helena Gervásio, Emilio Martorana, Alfredo Reder, Adamantia Athanasopoulou

► To cite this version:

Silvia Dimova, Cristina Silvia Polo Lopez, Maria Luisa Sousa, Guido Rianna, Emilio Bastidas-Arteaga, et al.. Impact of climate change on the corrosion of the European reinforced concrete building stock. Joint Research Centre. 2024. hal-04543682

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# Impact of climate change on the corrosion of the European reinforced concrete building stock

Silvia Dimova, Cristina Silvia Polo Lopez, Maria Luisa Sousa, Guido Rianna, Emilio Bastidas-Arteaga, Maria Nogal, Helena Gervásio, Emilio Martorana, Alfredo Reder, Adamantia Athanasopoulou

<figure><img src="image_1.png" /></figure>

## To cite this version:

Silvia Dimova, Cristina Silvia Polo Lopez, Maria Luisa Sousa, Guido Rianna, Emilio Bastidas-Arteaga, et al.. Impact of climate change on the corrosion of the European reinforced concrete building stock. Joint Research Centre. 2024. hal-04543682

HAL Id: hal-04543682

https://hal.science/hal-04543682v1

Submitted on 12 Apr 2024

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

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Distributed under a Creative Commons Attribution 4.0 International License
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# Impact of climate change on the corrosion of the European reinforced concrete building stock

Dimova, S., Polo López, C.S., Sousa, M.L., Rianna, G., Bastidas-Arteaga, E., Nogal, M., Gervásio, H., Martorana, E., Reder, A., Athanasopoulou, A. author(s)

Dimova, S., Polo López, C.S., Sousa, M.L. editor(s)

2024

Joint
Research
Centre
<figure><img src="image_3.png" /></figure>

# Impact of climate change on the corrosion of the European reinforced concrete building stock

Dimova, S., Polo López, C.S., Sousa, M.L., Rianna, G., Bastidas-Arteaga, E., Nogal, M., Gervásio, H., Martorana, E., Reder, A., Athanasopoulou, A. author(s)

Dimova, S., Polo López, C.S., Sousa, M.L. editor(s)

2024

Joint
Research
Centre
This document is a publication by the Joint Research Centre (JRC), the European Commission's science and knowledge service. It aims to provide evidence-based scientific support to the European policymaking process. The contents of this publication do not necessarily reflect the position or opinion of the European Commission. Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use that might be made of this publication. For information on the methodology and quality underlying the data used in this publication for which the source is neither Eurostat nor other Commission services, users should contact the referenced source. The designations employed and the presentation of material on the maps do not imply the expression of any opinion whatsoever on the part of the European Union concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

## Contact information

Name: Dr. Cristina Silvia Polo López, Scientific Project Officer, European Commission, Joint Research Centre, Directorate E
- Space, Security and Migration, Unit JRC.E.3 - Safety & Security of Buildings Unit

Address: TP480, Joint Research Centre, Via Enrico Fermi, 2749, 21027 Ispra, VA, Italy.

Email: [Cristina-Silvia.POLO-LOPEZ@ec.europa.eu](mailto:Cristina-Silvia.POLO-LOPEZ@ec.europa.eu)

Tel.: +39 0332-785527

## EU Science Hub

[https://joint-research-centre.ec.europa.eu](https://joint-research-centre.ec.europa.eu)

JRC137288

EUR 31900 EN

PDF

ISBN 978-92-68-14323-0

ISSN 1831-9424

doi:10.2760/016004

KJ-NA-31-900-EN-N

Luxembourg: Publications Office of the European Union, 2024

© European Union, 2024

<figure><img src="image_3.png" /></figure>

The reuse policy of the European Commission documents is implemented by the Commission Decision 2011/833/EU of 12 December 2011 on the reuse of Commission documents (OJ L 330, 14.12.2011, p. 39). Unless otherwise noted, the reuse of this document is authorised under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence ([https://creativecommons.org/licenses/by/4.0/](https://creativecommons.org/licenses/by/4.0/)). This means that reuse is allowed provided appropriate credit is given and any changes are indicated.

For any use or reproduction of photos or other material that is not owned by the European Union permission must be sought directly from the copyright holders. The European Union/European Atomic Energy Community does not own the IPR in relation to the following elements:

- Cover page illustration, © Cristina S. Polo López

- Page 19, Figure 1. Influence of RH in the carbonation depth, source: [Elsalamawy et al., 2019, for Creative Commons licensed via CC BY-NC-ND, https://doi.org/10.1016/j.aej.2019.10.008](https://doi.org/10.1016/j.aej.2019.10.008)

How to cite this report: European Commission, Joint Research Centre, Dimova, S., Polo López, C.S., Sousa, M.L., Rianna, G., Bastidas-Arteaga, E., Nogal, M., Gervásio, H., Martorana, E., Reder, A. and Athanasopoulou, A., *Impact of climate change on the corrosion of the European reinforced concrete building stock*, Dimova, S., Polo López, C.S. and Sousa, M.L. editor(s), Publications Office of the European Union, Luxembourg, 2024, [https://data.europa.eu/doi/10.2760/016004, JRC137288](https://data.europa.eu/doi/10.2760/016004, JRC137288).
This document is a publication by the Joint Research Centre (JRC), the European Commission's science and knowledge service. It aims to provide evidence-based scientific support to the European policymaking process. The contents of this publication do not necessarily reflect the position or opinion of the European Commission. Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use that might be made of this publication. For information on the methodology and quality underlying the data used in this publication for which the source is neither Eurostat nor other Commission services, users should contact the referenced source. The designations employed and the presentation of material on the maps do not imply the expression of any opinion whatsoever on the part of the European Union concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

## Contact information

Name: Dr. Cristina Silvia Polo López, Scientific Project Officer, European Commission, Joint Research Centre, Directorate E
- Space, Security and Migration, Unit JRC.E.3 - Safety & Security of Buildings Unit

Address: TP480, Joint Research Centre, Via Enrico Fermi, 2749, 21027 Ispra, VA, Italy.

Email: Cristina-Silvia.POLO-LOPEZ@ec.europa.eu

Tel.: +39 0332-785527

## EU Science Hub

https://joint-research-centre.ec.europa.eu

JRC137288

EUR 31900 EN

PDF

ISBN 978-92-68-14323-0

ISSN 1831-9424

doi:10.2760/016004

KJ-NA-31-900-EN-N

Luxembourg: Publications Office of the European Union, 2024

© European Union, 2024

<figure><img src="image_4.png" /></figure>

The reuse policy of the European Commission documents is implemented by the Commission Decision 2011/833/EU of 12 December 2011 on the reuse of Commission documents (OJ L 330, 14.12.2011, p. 39). Unless otherwise noted, the reuse of this document is authorised under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence (https://creativecommons.org/licenses/by/4.0/). This means that reuse is allowed provided appropriate credit is given and any changes are indicated.

For any use or reproduction of photos or other material that is not owned by the European Union permission must be sought directly from the copyright holders. The European Union/European Atomic Energy Community does not own the IPR in relation to the following elements:

- Cover page illustration, © Cristina S. Polo López

- Page 19, Figure 1. Influence of RH in the carbonation depth, source: [Elsalamawy et al., 2019, for Creative Commons licensed via CC BY-NC-ND, https://doi.org/10.1016/j.aej.2019.10.008]

How to cite this report: European Commission, Joint Research Centre, Dimova, S., Polo López, C.S., Sousa, M.L., Rianna, G., Bastidas-Arteaga, E., Nogal, M., Gervásio, H., Martorana, E., Reder, A. and Athanasopoulou, A., *Impact of climate change on the corrosion of the European reinforced concrete building stock*, Dimova, S., Polo López, C.S. and Sousa, M.L. editor(s), Publications Office of the European Union, Luxembourg, 2024, https://data.europa.eu/doi/10.2760/016004, JRC137288.
# Contents

<table><tr><td>Abstract</td><td>1</td></tr><tr><td>Foreword</td><td>2</td></tr><tr><td>Acknowledgements</td><td>5</td></tr><tr><td>Executive summary for policymakers</td><td>8</td></tr><tr><td>1 Introduction</td><td>11</td></tr><tr><td>1.1 EU policy context and background</td><td>11</td></tr><tr><td>1.2 JRC activities in support of adaptation of structural design to climate change</td><td>15</td></tr><tr><td>1.3 Organisation of the report</td><td>17</td></tr><tr><td>2 Corrosion of concrete structures due to climate change</td><td>18</td></tr><tr><td>2.1 Scope of the study</td><td>18</td></tr><tr><td>2.2 Mechanism of carbonation-induced corrosion influenced by climate change</td><td>19</td></tr><tr><td>2.3 Selection of model for assessment of carbonation depth</td><td>20</td></tr><tr><td>3 Modelling carbonation costs</td><td>22</td></tr><tr><td>3.1 Main considerations</td><td>22</td></tr><tr><td>3.2 Total normalized repair cost per square meter</td><td>23</td></tr><tr><td>3.2.1 Overview</td><td>23</td></tr><tr><td>3.2.2 Input data</td><td>23</td></tr><tr><td>Carbonation depth</td><td>23</td></tr><tr><td>Building characteristics for existing structures</td><td>24</td></tr><tr><td>Repair cost</td><td>26</td></tr><tr><td>3.2.3 Probability of corrosion initiation</td><td>27</td></tr><tr><td>3.2.4 Assessment of times to repair and associated costs</td><td>29</td></tr><tr><td>3.3 Total repair cost per year per category of buildings</td><td>30</td></tr><tr><td>3.3.1 Overview</td><td>30</td></tr><tr><td>3.3.2 Assessment of the exposed building surface and related cost</td><td>30</td></tr><tr><td>4 Introduction to the climatic data</td><td>33</td></tr><tr><td>4.1 Overview</td><td>33</td></tr><tr><td>4.2 Pan-European temperature values for recent decades and future projections</td><td>34</td></tr><tr><td>4.2.1 Climate simulation chains</td><td>34</td></tr><tr><td>4.2.2 Insights about the selected bias correction method and observational dataset</td><td>37</td></tr><tr><td>4.2.3 Potential differences in the gridded observational dataset throughout its releases</td><td>38</td></tr><tr><td>4.3 Variations of annual temperature</td><td>39</td></tr><tr><td>4.3.1 Variations over Europe and European countries</td><td>39</td></tr><tr><td>4.3.2 Variations over European capital cities</td><td>45</td></tr><tr><td>5 Characterization of the European building stock</td><td>50</td></tr><tr><td>5.1 Buildings inventory</td><td>50</td></tr><tr><td>5.2 Durability parameters of RC buildings</td><td>53</td></tr></table>
# Contents

<table><tr><td>Abstract</td><td>1</td></tr><tr><td>Foreword</td><td>2</td></tr><tr><td>Acknowledgements</td><td>5</td></tr><tr><td>Executive summary for policymakers</td><td>8</td></tr><tr><td>1 Introduction</td><td>11</td></tr><tr><td>1.1 EU policy context and background</td><td>11</td></tr><tr><td>1.2 JRC activities in support of adaptation of structural design to climate change</td><td>15</td></tr><tr><td>1.3 Organisation of the report</td><td>17</td></tr><tr><td>2 Corrosion of concrete structures due to climate change</td><td>18</td></tr><tr><td>2.1 Scope of the study</td><td>18</td></tr><tr><td>2.2 Mechanism of carbonation-induced corrosion influenced by climate change</td><td>19</td></tr><tr><td>2.3 Selection of model for assessment of carbonation depth</td><td>20</td></tr><tr><td>3 Modelling carbonation costs</td><td>22</td></tr><tr><td>3.1 Main considerations</td><td>22</td></tr><tr><td>3.2 Total normalized repair cost per square meter</td><td>23</td></tr><tr><td>3.2.1 Overview</td><td>23</td></tr><tr><td>3.2.2 Input data</td><td>23</td></tr><tr><td>Carbonation depth</td><td>23</td></tr><tr><td>Building characteristics for existing structures</td><td>24</td></tr><tr><td>Repair cost</td><td>26</td></tr><tr><td>3.2.3 Probability of corrosion initiation</td><td>27</td></tr><tr><td>3.2.4 Assessment of times to repair and associated costs</td><td>29</td></tr><tr><td>3.3 Total repair cost per year per category of buildings</td><td>30</td></tr><tr><td>3.3.1 Overview</td><td>30</td></tr><tr><td>3.3.2 Assessment of the exposed building surface and related cost</td><td>30</td></tr><tr><td>4 Introduction to the climatic data</td><td>33</td></tr><tr><td>4.1 Overview</td><td>33</td></tr><tr><td>4.2 Pan-European temperature values for recent decades and future projections</td><td>34</td></tr><tr><td>4.2.1 Climate simulation chains</td><td>34</td></tr><tr><td>4.2.2 Insights about the selected bias correction method and observational dataset</td><td>37</td></tr><tr><td>4.2.3 Potential differences in the gridded observational dataset throughout its releases</td><td>38</td></tr><tr><td>4.3 Variations of annual temperature</td><td>39</td></tr><tr><td>4.3.1 Variations over Europe and European countries</td><td>39</td></tr><tr><td>4.3.2 Variations over European capital cities</td><td>45</td></tr><tr><td>5 Characterization of the European building stock</td><td>50</td></tr><tr><td>5.1 Buildings inventory</td><td>50</td></tr><tr><td>5.2 Durability parameters of RC buildings</td><td>53</td></tr></table>
<table><tr><td>6</td><td>Climate change impact on the European reinforced concrete building stock</td><td>56</td></tr><tr><td>6.1</td><td>Overview of data and models used</td><td>56</td></tr><tr><td>6.2</td><td>Assessing carbonation damage</td><td>57</td></tr><tr><td>6.3</td><td>Assessing carbonation costs</td><td>67</td></tr><tr><td>7</td><td>Economic impact of climate change-induced corrosion of the European building stock</td><td>79</td></tr><tr><td>7.1</td><td>Coherence with previous studies on corrosion of reinforced concrete</td><td>79</td></tr><tr><td>7.2</td><td>Compatibility with PESETA IV study findings</td><td>80</td></tr><tr><td>7.3</td><td>Summary of the impact in time, magnitude and welfare loss</td><td>81</td></tr><tr><td>8</td><td>Adaptation strategies</td><td>84</td></tr><tr><td>8.1</td><td>Adaptation measures of new buildings</td><td>84</td></tr><tr><td>8.2</td><td>Adaptation measures of existing buildings</td><td>84</td></tr><tr><td>8.3</td><td>A resilience-based adaptation strategy</td><td>85</td></tr><tr><td>9</td><td>Conclusions</td><td>87</td></tr><tr><td></td><td>References</td><td>91</td></tr><tr><td></td><td>List of abbreviations and definitions</td><td>97</td></tr><tr><td></td><td>List of figures</td><td>99</td></tr><tr><td></td><td>List of tables</td><td>101</td></tr><tr><td></td><td>Annexes</td><td>102</td></tr><tr><td></td><td>Annex 1. Temperature scenarios for the capital cities of the 27 EU Member States</td><td>102</td></tr><tr><td></td><td>Annex 2. Annual carbonation depths for the capital cities of the 27 EU Member States</td><td>112</td></tr><tr><td></td><td>Annex 3. Probability of corrosion initiation for the capital cities of the 27 EU Member States</td><td>121</td></tr><tr><td></td><td>Annex 4. Informative tables</td><td>130</td></tr></table>
<table><tr><td>6</td><td>Climate change impact on the European reinforced concrete building stock</td><td>56</td></tr><tr><td>6.1</td><td>Overview of data and models used</td><td>56</td></tr><tr><td>6.2</td><td>Assessing carbonation damage</td><td>57</td></tr><tr><td>6.3</td><td>Assessing carbonation costs</td><td>67</td></tr><tr><td>7</td><td>Economic impact of climate change-induced corrosion of the European building stock</td><td>79</td></tr><tr><td>7.1</td><td>Coherence with previous studies on corrosion of reinforced concrete</td><td>79</td></tr><tr><td>7.2</td><td>Compatibility with PESETA IV study findings</td><td>80</td></tr><tr><td>7.3</td><td>Summary of the impact in time, magnitude and welfare loss</td><td>81</td></tr><tr><td>8</td><td>Adaptation strategies</td><td>84</td></tr><tr><td>8.1</td><td>Adaptation measures of new buildings</td><td>84</td></tr><tr><td>8.2</td><td>Adaptation measures of existing buildings</td><td>84</td></tr><tr><td>8.3</td><td>A resilience-based adaptation strategy</td><td>85</td></tr><tr><td>9</td><td>Conclusions</td><td>87</td></tr><tr><td></td><td>References</td><td>91</td></tr><tr><td></td><td>List of abbreviations and definitions</td><td>97</td></tr><tr><td></td><td>List of figures</td><td>99</td></tr><tr><td></td><td>List of tables</td><td>101</td></tr><tr><td></td><td>Annexes</td><td>102</td></tr><tr><td></td><td>Annex 1. Temperature scenarios for the capital cities of the 27 EU Member States</td><td>102</td></tr><tr><td></td><td>Annex 2. Annual carbonation depths for the capital cities of the 27 EU Member States</td><td>112</td></tr><tr><td></td><td>Annex 3. Probability of corrosion initiation for the capital cities of the 27 EU Member States</td><td>121</td></tr><tr><td></td><td>Annex 4. Informative tables</td><td>130</td></tr></table>
**Abstract**

The study provides assessment of the penetration of climate change induced carbonation in the concrete cover of the existing buildings in the EU Member States. It estimates the time for on-set of corrosion due to depleting of the cover of the reinforcement, and evaluates the repair costs under the moderate emissions scenario RCP4.5, and under the extreme scenario RCP8.5.

The results conclusively show that if there would be no climate change, the depth of carbonation would be much smaller than the depth of the concrete cover and would not lead to corrosion process. The study proves that the carbonation triggered by the long-term climate projections up to 2100 does not pose a threat to recent concrete buildings that follow the recommendations of the modern European standards for durability of the concrete cover. However, the climate change induced carbonation is expected to trigger corrosion in the building stock, which was designed upon the standards of the 20th century.

The projected cost for the EU Member States to repair the carbonation-triggered corrosion by the year 2100 is expected to reach approximately EUR 76 billion under RCP4.5 scenario and EUR 883 billion under RCP8.5 scenario. Under the more severe emissions scenario the corrosion process of 'old' buildings might start around 2050, while under the moderate scenario the onset of the process is expected after 2060.

The influence of the condition of the built environment on the Member States' economy is profound. The findings of the study necessitate development of guidance and regulations to mitigate the consequences of the climate change induced carbonation.
**Abstract**

The study provides assessment of the penetration of climate change induced carbonation in the concrete cover of the existing buildings in the EU Member States. It estimates the time for on-set of corrosion due to depleting of the cover of the reinforcement, and evaluates the repair costs under the moderate emissions scenario RCP4.5, and under the extreme scenario RCP8.5.

The results conclusively show that if there would be no climate change, the depth of carbonation would be much smaller than the depth of the concrete cover and would not lead to corrosion process. The study proves that the carbonation triggered by the long-term climate projections up to 2100 does not pose a threat to recent concrete buildings that follow the recommendations of the modern European standards for durability of the concrete cover. However, the climate change induced carbonation is expected to trigger corrosion in the building stock, which was designed upon the standards of the 20th century.

The projected cost for the EU Member States to repair the carbonation-triggered corrosion by the year 2100 is expected to reach approximately EUR 76 billion under RCP4.5 scenario and EUR 883 billion under RCP8.5 scenario. Under the more severe emissions scenario the corrosion process of 'old' buildings might start around 2050, while under the moderate scenario the onset of the process is expected after 2060.

The influence of the condition of the built environment on the Member States' economy is profound. The findings of the study necessitate development of guidance and regulations to mitigate the consequences of the climate change induced carbonation.
## Foreword

The construction ecosystem is of strategic importance to the European Union (EU), as it delivers the buildings and infrastructures needed by the rest of the economy and society, having a direct impact on the safety of persons and the quality of citizens' life. The construction ecosystem includes activities carried out during the whole lifecycle of buildings and infrastructure, namely the design, construction, maintenance, refurbishment and demolition. The construction ecosystem employs approximately 24.9 million people in the EU and provides a value added of EUR 1,158 billion (9.6% of the EU total). Within the EU, the construction products industry consists of 430,000 companies primarily small and medium-sized. These companies are crucial economic and social resources within European regions and cities, contributing significantly to local communities<fnref n="1" />,<fnref n="2" />

The construction ecosystem is a key element for the implementation of the European Single Market and many important EU strategies and initiatives. The **European Green Deal** (COM(2019) 640)<fnref n="3" /> launches a new growth strategy for the EU. It supports the transition of the EU to a fair and prosperous society that responds to the challenges posed by climate change and environmental degradation, improving the quality of life of current and future generations. The European Green Deal aims to achieve climate neutrality for Europe by 2050, mostly through emission reduction, investment in green technologies, and environmental protection. This goal of the European Green Deal is endorsed by both the Fit-for55 and the Climate Law and relies on numerous initiatives, noteworthy:

- the **New Circular Economy Action Plan (CEAP) (COM(2020)98)**<fnref n="4" /> and the New Industrial Strategy for Europe (COM(2020) 102) intending to accelerate the transition of the EU industry to a sustainable model based on the principles of circular economy;

- the **New EU Strategy on Adaptation to Climate Change (COM (2021) 82) final**<fnref n="5" />, setting out the pathway to prepare for the unavoidable impacts of climate change. The Strategy underlines the importance of increasing the preparedness of Europe's building stock to withstand the impacts of climate change. **Current report is part of the Commission Action 31 'Support the integration of climate resilience considerations into the criteria applicable to construction and renovation of buildings and critical infrastructure', specified in the Report on the implementation of the EU strategy on adaptation to climate change, SWD (2023) 338'**<fnref n="6" />.

- the **Renovation Wave for Europe (COM(2020) 662)**<fnref n="7" /> addressing the twin challenge of energy efficiency and energy affordability and aiming to double, at least, the annual renovation rates of the building stock (currently around 1%) and launching the **New European Bauhaus (COM(2021) 573) final**<fnref n="8" /> initiative;

<footnote n="1">¹ Council of the EU, Press release 30 June 2023, https://www.consilium.europa.eu/en/press/press-releases/2023/06/30/council-adopts-position-on-the-construction-products-regulation/</footnote>

<footnote n="2">² Transition Pathway For Construction, Dg Grow, https://Ec.Europa.Eu/Docsroom/Documents/53854</footnote>

<footnote n="3">³ European Commission. (2019). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, The European Green Deal, Brussels, 11.12.2019, COM(2019) 640 final</footnote>

<footnote n="4">⁴ European Commission (2020). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, A new Circular Economy Action Plan. For a cleaner and more competitive Europe, Brussels, 11.3.2020, COM(2020) 98 final.</footnote>

<footnote n="5">⁵ European Commission (2021). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions. Forging a climate-resilient Europe – the new EU Strategy on Adaptation to Climate Change (COM(2021) 82 final), Brussels, 24.2.2021.</footnote>

<footnote n="6">⁶ Commission Staff Working Document, Report on the implementation of the EU strategy on adaptation to climate change. Accompanying the document 'Report from the Commission to the European Parliament and the Council EU Climate Action Progress Report 2023', Brussels, 24.10.2023, SWD (2023) 338 final, https://data.consilium.europa.eu/doc/document/ST-14650-2023-ADD-1/en/pdf</footnote>

<footnote n="7">⁷ European Commission (2020). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions. A Renovation Wave for Europe - greening our buildings, creating jobs, improving lives, Brussels, 14.10.2020, COM(2020) 662 final</footnote>

<footnote n="8">⁸ European Commission (2021). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions, New European Bauhaus Beautiful, Sustainable, Together, Brussels, 15.9.2021 COM(2021) 573 final</footnote>
## Foreword

The construction ecosystem is of strategic importance to the European Union (EU), as it delivers the buildings and infrastructures needed by the rest of the economy and society, having a direct impact on the safety of persons and the quality of citizens' life. The construction ecosystem includes activities carried out during the whole lifecycle of buildings and infrastructure, namely the design, construction, maintenance, refurbishment and demolition. The construction ecosystem employs approximately 24.9 million people in the EU and provides a value added of EUR 1,158 billion (9.6% of the EU total). Within the EU, the construction products industry consists of 430,000 companies primarily small and medium-sized. These companies are crucial economic and social resources within European regions and cities, contributing significantly to local communities<fnref n="1" />,<fnref n="2" />

The construction ecosystem is a key element for the implementation of the European Single Market and many important EU strategies and initiatives. The **European Green Deal** (COM(2019) 640)<fnref n="3" /> launches a new growth strategy for the EU. It supports the transition of the EU to a fair and prosperous society that responds to the challenges posed by climate change and environmental degradation, improving the quality of life of current and future generations. The European Green Deal aims to achieve climate neutrality for Europe by 2050, mostly through emission reduction, investment in green technologies, and environmental protection. This goal of the European Green Deal is endorsed by both the Fit-for55 and the Climate Law and relies on numerous initiatives, noteworthy:

- the **New Circular Economy Action Plan (CEAP) (COM(2020)98)**<fnref n="4" /> and the New Industrial Strategy for Europe (COM(2020) 102) intending to accelerate the transition of the EU industry to a sustainable model based on the principles of circular economy;

- the **New EU Strategy on Adaptation to Climate Change (COM (2021) 82) final)**<fnref n="5" />, setting out the pathway to prepare for the unavoidable impacts of climate change. The Strategy underlines the importance of increasing the preparedness of Europe's building stock to withstand the impacts of climate change. **Current report is part of the Commission Action 31 'Support the integration of climate resilience considerations into the criteria applicable to construction and renovation of buildings and critical infrastructure', specified in the Report on the implementation of the EU strategy on adaptation to climate change, SWD (2023) 338'**<fnref n="6" />.

- the **Renovation Wave for Europe (COM(2020) 662)**<fnref n="7" /> addressing the twin challenge of energy efficiency and energy affordability and aiming to double, at least, the annual renovation rates of the building stock (currently around 1%) and launching the **New European Bauhaus (COM(2021) 573) final**<fnref n="8" /> initiative;

<footnote n="1">¹ Council of the EU, Press release 30 June 2023, https://www.consilium.europa.eu/en/press/press-releases/2023/06/30/council-adopts-position-on-the-construction-products-regulation/</footnote>

<footnote n="2">² Transition Pathway For Construction, Dg Grow, https://Ec.Europa.Eu/Docsroom/Documents/53854</footnote>

<footnote n="3">³ European Commission. (2019). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, The European Green Deal, Brussels, 11.12.2019, COM(2019) 640 final</footnote>

<footnote n="4">⁴ European Commission (2020). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, A new Circular Economy Action Plan. For a cleaner and more competitive Europe, Brussels, 11.3.2020, COM(2020) 98 final.</footnote>

<footnote n="5">⁵ European Commission (2021). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions. Forging a climate-resilient Europe - the new EU Strategy on Adaptation to Climate Change (COM(2021) 82 final), Brussels, 24.2.2021.</footnote>

<footnote n="6">⁶ Commission Staff Working Document, Report on the implementation of the EU strategy on adaptation to climate change. Accompanying the document 'Report from the Commission to the European Parliament and the Council EU Climate Action Progress Report 2023', Brussels, 24.10.2023, SWD (2023) 338 final, https://data.consilium.europa.eu/doc/document/ST-14650-2023-ADD-1/en/pdf</footnote>

<footnote n="7">⁷ European Commission (2020). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions. A Renovation Wave for Europe - greening our buildings, creating jobs, improving lives, Brussels, 14.10.2020, COM(2020) 662 final</footnote>

<footnote n="8">⁸ European Commission (2021). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions, New European Bauhaus Beautiful, Sustainable, Together, Brussels, 15.9.2021 COM(2021) 573 final</footnote>
— the review (COM(2022)144)<fnref n="9" /> of the **Construction Products Regulation** (Regulation (EU) No 305/2011) to ensure that the design of new and renovated buildings at all stages is in line with the needs of the circular economy, and lead to increased digitalisation and climate-proofing of the building stock.

The European Council's Conclusions in December 2022 led to the Commission introducing a Green Deal Industrial Plan (GDIP) on February 1, 2023, to improve Europe's net-zero industry's competitiveness and support climate neutrality. The new '**Green Deal industrial plan for the net-zero age**' (COM(2023)0062)<fnref n="10" /> includes legislative proposals, such as the **net-zero industry act (NZIA)** of March 16, 2023 (COM(2023)0161)<fnref n="11" />, which simplifies regulatory frameworks and promotes European standards for key technologies.

European standardisation is crucial for sustainable growth, innovation, and competitiveness in the rapidly changing world. Recognizing that the EU's ambitions towards a climate neutral economy cannot be delivered without leveraging the European standardization system, the European Commission presented a **new Standardization Strategy (COM(2022)31)**<fnref n="12" />, to enable global leadership of EU standards in promoting values and a resilient, green and digital Single Market. The Strategy spots standards as '*the silent foundation of the EU Single Market and global competitiveness*', since they are '*invisible but a fundamental part of our daily life*'. European standards are thus embedded in the EU policy objectives and have a key role to achieve a climate neutral, resilient and circular economy.

The EU has already put in place a comprehensive legislative and regulatory framework for the construction sector, including related European Standards (EN). Within this framework, the Eurocodes are a series of 10 European Standards, EN 1990 to EN 1999, providing common technical rules for the design of buildings and other civil engineering works. The Commission Recommendation 2003/887/EC on the implementation and use of the Eurocodes for construction works and structural construction products recommends undertaking research to facilitate the integration into the Eurocodes of the latest developments in scientific and technological knowledge.

In this context, DG GROW of the European Commission issued in 2012 the Mandate M/515 to initiate a process of further evolution of the Eurocodes, incorporating improvements to the existing standards and extending their scope. The detailed work programme prepared by CEN's Technical Committee (TC) 250 'Structural Eurocodes' (CEN/TC250) as a reply to M/515 ensures that the second generation of the Eurocodes continue to be the most comprehensive and advanced state-of-the-art codes for structural and geotechnical design in the world.

These recent EU policies and initiatives will impact the building sector development, the construction market evolution and the capacity for adaptation to climate challenges in the future. Climate change significantly impacts buildings in Europe, causing heat waves, storms, heavy precipitation, and flooding events. To address these increasing numbers of hazards, effective adaptation measures must be resilient to multiple hazards. Technical guidance on climate-adaptation measures is needed for both new and existing buildings across different climatic zones. Solutions should reduce climate risks, and stakeholders should be oriented to improve building performance. Supporting the development and alignment of key EU policies is fundamental. A first approach is recently issued by European Commission reports<fnref n="13" />,<fnref n="14" /> providing EU-level technical guidance on adapting buildings to climate change.

Further, in 2014, the European Commission issued the Mandate M/526 requesting the European Standardisation Organisations (ESOs) to contribute to building and maintaining a more climate resilient infrastructure throughout the EU in the three priority sectors: transport infrastructure, energy infrastructure, and

<footnote n="9">⁹ Proposal for a REGULATION OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011, Brussels, 30.3.2022, COM(2022) 144 final, 2022/0094 (COD).</footnote>

<footnote n="10">¹⁰ European Commission (2023). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, *A Green Deal Industrial Plan for the Net-Zero Age*, Brussels, 1.2.2023, COM(2023) 62 final</footnote>

<footnote n="11">¹¹ Proposal for a regulation of the European Parliament and of the Council on establishing a framework of measures for strengthening Europe's net-zero technology products manufacturing ecosystem (*Net Zero Industry Act*), Brussels, Brussels, 16.3.2023, COM(2023) 161</footnote>

<footnote n="12">¹² European Commission (2022). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, *An EU Strategy on Standardisation*, Brussels, 2.2.2022, COM(2022) 31 final</footnote>

<footnote n="13">¹³ European Commission, Directorate-General for Climate Action, EU-level technical guidance on adapting buildings to climate change, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/558395</footnote>

<footnote n="14">¹⁴ European Commission, Directorate-General for Climate Action, EU-level technical guidance on adapting buildings to climate change: best practice guidance, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/585141</footnote>
— the review (COM(2022)144)<fnref n="9" /> of the **Construction Products Regulation** (Regulation (EU) No 305/2011) to ensure that the design of new and renovated buildings at all stages is in line with the needs of the circular economy, and lead to increased digitalisation and climate-proofing of the building stock.

The European Council's Conclusions in December 2022 led to the Commission introducing a Green Deal Industrial Plan (GDIP) on February 1, 2023, to improve Europe's net-zero industry's competitiveness and support climate neutrality. The new '**Green Deal industrial plan for the net-zero age**' (COM(2023)0062)<fnref n="10" /> includes legislative proposals, such as the **net-zero industry act (NZIA)** of March 16, 2023 (COM(2023)0161)<fnref n="11" />, which simplifies regulatory frameworks and promotes European standards for key technologies.

European standardisation is crucial for sustainable growth, innovation, and competitiveness in the rapidly changing world. Recognizing that the EU's ambitions towards a climate neutral economy cannot be delivered without leveraging the European standardization system, the European Commission presented a **new Standardization Strategy (COM(2022)31)**<fnref n="12" />, to enable global leadership of EU standards in promoting values and a resilient, green and digital Single Market. The Strategy spots standards as '*the silent foundation of the EU Single Market and global competitiveness*', since they are '*invisible but a fundamental part of our daily life*'. European standards are thus embedded in the EU policy objectives and have a key role to achieve a climate neutral, resilient and circular economy.

The EU has already put in place a comprehensive legislative and regulatory framework for the construction sector, including related European Standards (EN). Within this framework, the Eurocodes are a series of 10 European Standards, EN 1990 to EN 1999, providing common technical rules for the design of buildings and other civil engineering works. The Commission Recommendation 2003/887/EC on the implementation and use of the Eurocodes for construction works and structural construction products recommends undertaking research to facilitate the integration into the Eurocodes of the latest developments in scientific and technological knowledge.

In this context, DG GROW of the European Commission issued in 2012 the Mandate M/515 to initiate a process of further evolution of the Eurocodes, incorporating improvements to the existing standards and extending their scope. The detailed work programme prepared by CEN's Technical Committee (TC) 250 'Structural Eurocodes' (CEN/TC250) as a reply to M/515 ensures that the second generation of the Eurocodes continue to be the most comprehensive and advanced state-of-the-art codes for structural and geotechnical design in the world.

These recent EU policies and initiatives will impact the building sector development, the construction market evolution and the capacity for adaptation to climate challenges in the future. Climate change significantly impacts buildings in Europe, causing heat waves, storms, heavy precipitation, and flooding events. To address these increasing numbers of hazards, effective adaptation measures must be resilient to multiple hazards. Technical guidance on climate-adaptation measures is needed for both new and existing buildings across different climatic zones. Solutions should reduce climate risks, and stakeholders should be oriented to improve building performance. Supporting the development and alignment of key EU policies is fundamental. A first approach is recently issued by European Commission reports<fnref n="13" />,<fnref n="14" /> providing EU-level technical guidance on adapting buildings to climate change.

Further, in 2014, the European Commission issued the Mandate M/526 requesting the European Standardisation Organisations (ESOs) to contribute to building and maintaining a more climate resilient infrastructure throughout the EU in the three priority sectors: transport infrastructure, energy infrastructure, and

<footnote n="9">⁹ Proposal for a REGULATION OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011, Brussels, 30.3.2022, COM(2022) 144 final, 2022/0094 (COD).</footnote>

<footnote n="10">¹⁰ European Commission (2023). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, *A Green Deal Industrial Plan for the Net-Zero Age*, Brussels, 1.2.2023, COM(2023) 62 final</footnote>

<footnote n="11">¹¹ Proposal for a regulation of the European Parliament and of the Council on establishing a framework of measures for strengthening Europe's net-zero technology products manufacturing ecosystem (*Net Zero Industry Act*), Brussels, Brussels, 16.3.2023, COM(2023) 161</footnote>

<footnote n="12">¹² European Commission (2022). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions, *An EU Strategy on Standardisation*, Brussels, 2.2.2022, COM(2022) 31 final</footnote>

<footnote n="13">¹³ European Commission, Directorate-General for Climate Action, EU-level technical guidance on adapting buildings to climate change, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/558395</footnote>

<footnote n="14">¹⁴ European Commission, Directorate-General for Climate Action, EU-level technical guidance on adapting buildings to climate change: best practice guidance, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/585141</footnote>
buildings/construction. The activities of Project Team 1 "Linking standards for infrastructures to future climatic condition" working under Mandate M/526 aimed at increase resilience to climate change of European infrastructure and related sectors. The works of the Project Team, participated by the European Commission's Joint Research Centre (JRC), identified data needs in the Eurocodes and other infrastructure standards, considering that of standards should be flexible in the use of best climate data as the science evolves.

The JRC supports the uptake of climate adaptation into standardisation for construction by producing pilot studies on the trends of climatic loading on structures and on adverse phenomena triggered by the climate change. Recent studies and publications highlight the need to update the climatic loading for structural design in Europe, viewing at the snow loading (Croce et al., 2018¹⁵) and thermal loading (Athanasopoulou et al., 2020¹⁶), and propose methodology for extracting climatic loading from available datasets to prepare national maps for design thermal actions (Rianna et al., 2023¹⁷). Climate change's impact on concrete and steel structures is expected to increase corrosion and deterioration in the structures (Sousa et al. 2020¹⁸).

This JRC Report quantitatively estimates the impact of climate change on the corrosion of the European reinforced concrete building stock. The aim is to provide scientific-based evidence to support the formulation of effective adaptation strategies for the existing and future building stock at a pan-European level and assess the necessary adaptation measures in design standards to maintain acceptable levels of safety, serviceability and durability.

**The authors have sought to present useful and consistent information in this report. However, users of the information contained in this report must satisfy themselves with its suitability for the purpose for which they intend to use it.**

The report is available to download from the JRC Publication Repository (https://publications.jrc.ec.europa.eu/repository/) and from 'Eurocodes: Building the future' website (http://eurocodes.jrc.ec.europa.eu).

François Augendre

Head of Unit Safety and Security of Buildings, Joint Research Centre of the European Commission

Georgios Tsionis

Project Leader 'Safe, smart and green buildings', Safety and Security of Buildings Unit, Joint Research Centre of the European Commission

March 2024

<footnote n="15">¹⁵ Croce, P., Formichi, P., Landi, F., Mercogliano, P., Bucchignani, E., Dosio, A., Dimova, S., 'The snow load in Europe and the climate change', *Climate Risk Management*, Vol. 20, 2018, pp. 138-154, ISSN 2212-0963, https://doi.org/10.1016/j.crm.2018.03.001.</footnote>

<footnote n="16">¹⁶ Athanasopoulou, A., Raposo De M. Do N. E S. De Sotto Mayor, M., Dimova, S., Guido, R., Mercogliano, P., Villani, V., Croce, P., Landi, F., Formichi, P. and Markova, J., *Thermal design of structures and the changing climate*, EUR 30302 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20777-1, doi:10.2760/40470, JRC121351.</footnote>

<footnote n="17">¹⁷ Rianna, G., Reder, A., Sousa, M.L., Dimova, S., 'Harmonised procedure to update thermal loads in the Eurocodes. Case study for Italy', *Climate Services*, Vol. 30, 2023, 100391, ISSN 2405-8807, https://doi.org/10.1016/j.cliser.2023.100391.</footnote>

<footnote n="18">¹⁸ Sousa, M.L., M., Dimova, S., Athanasopoulou, A., Rianna, G., Mercogliano, P., Villani, V., Nogal, M., Dos Santos Gervasio, H., Neves, L., Bastidas-Arteaga, E. and Tsionis, G., *Expected implications of climate change on the corrosion of structures*, EUR 30303 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20782-5, doi:10.2760/05229, JRC121312.</footnote>
buildings/construction. The activities of Project Team 1 "Linking standards for infrastructures to future climatic condition" working under Mandate M/526 aimed at increase resilience to climate change of European infrastructure and related sectors. The works of the Project Team, participated by the European Commission's Joint Research Centre (JRC), identified data needs in the Eurocodes and other infrastructure standards, considering that of standards should be flexible in the use of best climate data as the science evolves.

The JRC supports the uptake of climate adaptation into standardisation for construction by producing pilot studies on the trends of climatic loading on structures and on adverse phenomena triggered by the climate change. Recent studies and publications highlight the need to update the climatic loading for structural design in Europe, viewing at the snow loading (Croce et al., 2018¹⁵) and thermal loading (Athanasopoulou et al., 2020¹⁶), and propose methodology for extracting climatic loading from available datasets to prepare national maps for design thermal actions (Rianna et al., 2023¹⁷). Climate change's impact on concrete and steel structures is expected to increase corrosion and deterioration in the structures (Sousa et al. 2020¹⁸).

This JRC Report quantitatively estimates the impact of climate change on the corrosion of the European reinforced concrete building stock. The aim is to provide scientific-based evidence to support the formulation of effective adaptation strategies for the existing and future building stock at a pan-European level and assess the necessary adaptation measures in design standards to maintain acceptable levels of safety, serviceability and durability.

**The authors have sought to present useful and consistent information in this report. However, users of the information contained in this report must satisfy themselves with its suitability for the purpose for which they intend to use it.**

The report is available to download from the JRC Publication Repository (https://publications.jrc.ec.europa.eu/repository/) and from 'Eurocodes: Building the future' website (http://eurocodes.jrc.ec.europa.eu).

François Augendre

Head of Unit Safety and Security of Buildings, Joint Research Centre of the European Commission

Georgios Tsionis

Project Leader 'Safe, smart and green buildings', Safety and Security of Buildings Unit, Joint Research Centre of the European Commission

March 2024

<footnote n="15">¹⁵ Croce, P., Formichi, P., Landi, F., Mercogliano, P., Bucchignani, E., Dosio, A., Dimova, S., 'The snow load in Europe and the climate change', *Climate Risk Management*, Vol. 20, 2018, pp. 138-154, ISSN 2212-0963, https://doi.org/10.1016/j.crm.2018.03.001.</footnote>

<footnote n="16">¹⁶ Athanasopoulou, A., Raposo De M. Do N. E S. De Sotto Mayor, M., Dimova, S., Guido, R., Mercogliano, P., Villani, V., Croce, P., Landi, F., Formichi, P. and Markova, J., *Thermal design of structures and the changing climate*, EUR 30302 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20777-1, doi:10.2760/40470, JRC121351.</footnote>

<footnote n="17">¹⁷ Rianna, G., Reder, A., Sousa, M.L., Dimova, S., 'Harmonised procedure to update thermal loads in the Eurocodes. Case study for Italy', *Climate Services*, Vol. 30, 2023, 100391, ISSN 2405-8807, https://doi.org/10.1016/j.cliser.2023.100391.</footnote>

<footnote n="18">¹⁸ Sousa, M.L., M., Dimova, S., Athanasopoulou, A., Rianna, G., Mercogliano, P., Villani, V., Nogal, M., Dos Santos Gervasio, H., Neves, L., Bastidas-Arteaga, E. and Tsionis, G., *Expected implications of climate change on the corrosion of structures*, EUR 30303 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20782-5, doi:10.2760/05229, JRC121312.</footnote>
# Acknowledgements

The work in this report was achieved within the framework of the Administrative Arrangements between the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs and the Joint Research Centre, supporting policies and standards for sustainable construction ecosystem.

The authors acknowledge the World Climate Research Programme's Working Group on Regional Climate, and the Working Group on Coupled Modelling, former coordinating body of CORDEX and responsible panel for CMIP5. We also thank the climate modelling groups (listed in Table 1 of Chapter 3) for producing and making available their model output. We also acknowledge the Earth System Grid Federation infrastructure an international effort led by the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison, the European Network for Earth System Modelling and other partners in the Global Organisation for Earth System Science Portals (GO-ESSP).

The report builds on the activities of a scientific network addressing the implications of the climate change on structural design. The authors acknowledge the support and cooperation of its members not participating as authors in the current report, namely:

- Pietro CROCE, Convenor CEN/TC 250/HG 'Bridges', University of Pisa, Italy

- Alessandro DOSIO, European Commission Joint Research Centre, Ispra, Italy

- Paolo FORMICHI, Chairman CEN/TC 250/SC10 'Basis of Structural Design', University of Pisa, Italy

- Georgios TSIONIS, Project Leader 'Safe, smart and green buildings', European Commission Joint Research Centre, Ispra, Italy

- Nikolaos MALAKATAS, Chairman CEN/TC 250 SC1 'Actions on structures', Greece

- Jana MARKOVA, Czech Technical University in Prague, Klokner Institute, Czechia

The findings of the report have been subject to peer review from European Commission's colleagues to whom the authors would like to express their acknowledgement:

- Manfred FUCHS, Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROW)

- Johannes KLUMPERS, Directorate-General for Climate Action (DG CLIMA)

# Authors

## List of Authors and Editors

### CHAPTER 1 INTRODUCTION

Adamantia ATHANASOPOULOU, Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

### CHAPTER 2 CORROSION OF CONCRETE STRUCTURES DUE TO CLIMATE CHANGE

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal
# Acknowledgements

The work in this report was achieved within the framework of the Administrative Arrangements between the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs and the Joint Research Centre, supporting policies and standards for sustainable construction ecosystem.

The authors acknowledge the World Climate Research Programme's Working Group on Regional Climate, and the Working Group on Coupled Modelling, former coordinating body of CORDEX and responsible panel for CMIP5. We also thank the climate modelling groups (listed in Table 1 of Chapter 3) for producing and making available their model output. We also acknowledge the Earth System Grid Federation infrastructure an international effort led by the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison, the European Network for Earth System Modelling and other partners in the Global Organisation for Earth System Science Portals (GO-ESSP).

The report builds on the activities of a scientific network addressing the implications of the climate change on structural design. The authors acknowledge the support and cooperation of its members not participating as authors in the current report, namely:

- Pietro CROCE, Convenor CEN/TC 250/HG 'Bridges', University of Pisa, Italy

- Alessandro DOSIO, European Commission Joint Research Centre, Ispra, Italy

- Paolo FORMICHI, Chairman CEN/TC 250/SC10 'Basis of Structural Design', University of Pisa, Italy

- Georgios TSIONIS, Project Leader 'Safe, smart and green buildings', European Commission Joint Research Centre, Ispra, Italy

- Nikolaos MALAKATAS, Chairman CEN/TC 250 SC1 'Actions on structures', Greece

- Jana MARKOVA, Czech Technical University in Prague, Klokner Institute, Czechia

The findings of the report have been subject to peer review from European Commission's colleagues to whom the authors would like to express their acknowledgement:

- Manfred FUCHS, Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROW)

- Johannes KLUMPERS, Directorate-General for Climate Action (DG CLIMA)

# Authors

## List of Authors and Editors

### CHAPTER 1 INTRODUCTION

Adamantia ATHANASOPOULOU, Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

### CHAPTER 2 CORROSION OF CONCRETE STRUCTURES DUE TO CLIMATE CHANGE

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal
Maria NOGAL MACHO University of Technology, Delft, the Netherlands

Helena GERVÁSIO Coimbra University, Portugal

## CHAPTER 3 MODELLING CARBONATION COSTS

Emilio BASTIDAS-ARTEAGA La Rochelle University, La Rochelle, France

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

## CHAPTER 4 INTRODUCTION TO THE CLIMATIC DATA

Guido RIANNA, Alfredo REDER CMCC Foundation - Euro-Mediterranean Center on Climate Change, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Silvia DIMOVA European Commission Joint Research Centre, Ispra, Italy

## CHAPTER 5 CHARACTERIZATION OF THE EUROPEAN BUILDING STOCK

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Helena GERVÁSIO Coimbra University, Portugal

Emilio MARTORANA Fincons S.p.A., Italy
External consultant for the European Commission

## CHAPTER 6 CLIMATE CHANGE IMPACT ON THE EUROPEAN REINFORCED CONCRETE BUILDING STOCK

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Emilio MARTORANA Fincons S.p.A., Italy
External consultant for the European Commission
Maria NOGAL MACHO University of Technology, Delft, the Netherlands

Helena GERVÁSIO Coimbra University, Portugal

## CHAPTER 3 MODELLING CARBONATION COSTS

Emilio BASTIDAS-ARTEAGA La Rochelle University, La Rochelle, France

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

## CHAPTER 4 INTRODUCTION TO THE CLIMATIC DATA

Guido RIANNA, Alfredo REDER CMCC Foundation - Euro-Mediterranean Center on Climate Change, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Silvia DIMOVA European Commission Joint Research Centre, Ispra, Italy

## CHAPTER 5 CHARACTERIZATION OF THE EUROPEAN BUILDING STOCK

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Helena GERVÁSIO Coimbra University, Portugal

Emilio MARTORANA Fincons S.p.A., Italy
External consultant for the European Commission

## CHAPTER 6 CLIMATE CHANGE IMPACT ON THE EUROPEAN REINFORCED CONCRETE BUILDING STOCK

Silvia DIMOVA, Cristina S. POLO LÓPEZ European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

Emilio MARTORANA Fincons S.p.A., Italy
External consultant for the European Commission
# CHAPTER 7 ECONOMIC IMPACT OF CLIMATE CHANGE-INDUCED CORROSION OF THE EUROPEAN BUILDING STOCK

Cristina S. POLO LÓPEZ, Silvia DIMOVA
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

# CHAPTER 8 ADAPTATION STRATEGIES

Maria NOGAL MACHO
University of Technology, Delft, the Netherlands

# CHAPTER 9 CONCLUSIONS

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

# Editors

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal
**CHAPTER 7**
**ECONOMIC IMPACT OF CLIMATE CHANGE-INDUCED CORROSION OF THE**
**EUROPEAN BUILDING STOCK**

Cristina S. POLO LÓPEZ, Silvia DIMOVA
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal

**CHAPTER 8**
**ADAPTATION STRATEGIES**

Maria NOGAL MACHO
University of Technology, Delft, the Netherlands

**CHAPTER 9**
**CONCLUSIONS**

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

**Editors**

Silvia DIMOVA, Cristina S. POLO LÓPEZ
European Commission Joint Research Centre, Ispra, Italy

Maria Luísa SOUSA
Former European Commission Joint Research Centre, Ispra, Italy
Currently Portuguese National Laboratory for Civil Engineering, Lisbon, Portugal
# Executive summary for policymakers

## Background

Climate change poses a significant threat to humans and ecosystems, with 3.3 to 3.6 billion people living in high sensitive climate change environments (IPCC, 2023¹⁹). The adaptation of the built environment to climate change is imperative for safeguarding people, property, and the economy from its detrimental effects, while fostering sustainable and equitable communities prepared for future challenges. This priority is bolstered by several EU initiatives, including the New Circular Economy Action Plan (CEAP) (COM(2020)98), the New EU Strategy on Adaptation to Climate Change (COM(2021) 82 final), the Renovation Wave for Europe (COM(2020) 662), and the review of the Construction Products Regulation (COM(2022)144). The current study aligns with the EU strategy on adaptation to climate change implementation report (SWD (2023) 338) and in particular with the Commission Action 31, which aims to integrate climate resilience considerations into construction and renovation criteria.

Carbonation of concrete is a chemical process where carbon dioxide from the air reacts with the calcium hydroxide in the concrete to form calcium carbonate. This reaction can lead to decrease in the concrete's strength and durability, and to corrosion of the concrete's reinforcing steel. The study is the first evaluation of the implications of the climate change induced carbonation on the entire concrete building stock in the EU Member States. It provides assessment of the penetration of climate change induced carbonation in the concrete cover of the existing buildings in the EU Member States, in the period up to year 2100. It estimates the time for on-set of corrosion, and evaluates the repair costs under the moderate concentration scenario RCP4.5²⁰, and under the extreme scenario RCP8.5 (no mitigation action).

Climate data for the study derive from 11 climate simulation chains included in the EURO-CORDEX<fnref n="21" /> initiative bias-adjusted and by exploiting the EOBSv10 gridded dataset<fnref n="22" />. The progression of carbonation depth model incorporates building durability characteristics and environmental exposure over time, with atmospheric CO₂ concentration and mean air temperature as input variables. The report does not specifically address relative humidity (RH) variation effects on corrosion rates due to the need for more detailed scale data for accurate estimations.

The building stock database encompasses over 30 million reinforced concrete buildings in the EU Member States. They were aggregated in two major groups to reflect their age, called 'old' (assumed built before the year 2000 according to standards of the 20th century) and 'recent' (assumed built after year 2000 according to the contemporary standards). The assessment of the repair cost assumes that the repair occurs after the depletion of the concrete cover and before a significant loss of cross-sectional area of the reinforcement, thus considering a corrective repair of the exposed building surface, using a uniform price across all countries.

## Key findings

1. The results for both the old and the recent buildings conclusively show that, without the expected variations induced by climate change, the carbonation due to natural aging of buildings would not lead to corrosion.

2. Recent buildings constructed to current European standards are less susceptible to carbonation-induced corrosion due to climate change. In contrast, older buildings are at a higher risk.

3. By 2100, projected total repair costs for EU Member States amount to approximately EUR 76 billion under RCP4.5 and EUR 883 billion under RCP8.5, with the most affected countries varying between the scenarios. Italy, Portugal, Spain and Denmark would have to afford the highest total repair costs under RCP4.5. Under the severe RCP8.5 scenario, Poland, France, Germany, and Czechia would face the highest total repair costs.

<footnote n="19">¹⁹ IPCC, 2023: Summary for Policymakers. In: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, pp. 1-34, doi: 10.59327/IPCC/AR6-9789291691647.00</footnote>

<footnote n="20">²⁰ 5th Assessment Report of Intergovernmental Panel on Climate Change (2013)</footnote>

<footnote n="21">²¹ https://www.euro-cordex.net/</footnote>

<footnote n="22">²² http://jeodpp.jrc.ec.europa.eu/ftp/jrc-opendata/LISCOAST/10011/LATEST/</footnote>
# Executive summary for policymakers

## Background

Climate change poses a significant threat to humans and ecosystems, with 3.3 to 3.6 billion people living in high sensitive climate change environments (IPCC, 2023¹⁹). The adaptation of the built environment to climate change is imperative for safeguarding people, property, and the economy from its detrimental effects, while fostering sustainable and equitable communities prepared for future challenges. This priority is bolstered by several EU initiatives, including the New Circular Economy Action Plan (CEAP) (COM(2020)98), the New EU Strategy on Adaptation to Climate Change (COM(2021) 82 final), the Renovation Wave for Europe (COM(2020) 662), and the review of the Construction Products Regulation (COM(2022)144). The current study aligns with the EU strategy on adaptation to climate change implementation report (SWD (2023) 338) and in particular with the Commission Action 31, which aims to integrate climate resilience considerations into construction and renovation criteria.

Carbonation of concrete is a chemical process where carbon dioxide from the air reacts with the calcium hydroxide in the concrete to form calcium carbonate. This reaction can lead to decrease in the concrete's strength and durability, and to corrosion of the concrete's reinforcing steel. The study is the first evaluation of the implications of the climate change induced carbonation on the entire concrete building stock in the EU Member States. It provides assessment of the penetration of climate change induced carbonation in the concrete cover of the existing buildings in the EU Member States, in the period up to year 2100. It estimates the time for on-set of corrosion, and evaluates the repair costs under the moderate concentration scenario RCP4.5²⁰, and under the extreme scenario RCP8.5 (no mitigation action).

Climate data for the study derive from 11 climate simulation chains included in the EURO-CORDEX<fnref n="21" /> initiative bias-adjusted and by exploiting the EOBSv10 gridded dataset<fnref n="22" />. The progression of carbonation depth model incorporates building durability characteristics and environmental exposure over time, with atmospheric CO₂ concentration and mean air temperature as input variables. The report does not specifically address relative humidity (RH) variation effects on corrosion rates due to the need for more detailed scale data for accurate estimations.

The building stock database encompasses over 30 million reinforced concrete buildings in the EU Member States. They were aggregated in two major groups to reflect their age, called 'old' (assumed built before the year 2000 according to standards of the 20th century) and 'recent' (assumed built after year 2000 according to the contemporary standards). The assessment of the repair cost assumes that the repair occurs after the depletion of the concrete cover and before a significant loss of cross-sectional area of the reinforcement, thus considering a corrective repair of the exposed building surface, using a uniform price across all countries.

## Key findings

1. The results for both the old and the recent buildings conclusively show that, without the expected variations induced by climate change, the carbonation due to natural aging of buildings would not lead to corrosion.

2. Recent buildings constructed to current European standards are less susceptible to carbonation-induced corrosion due to climate change. In contrast, older buildings are at a higher risk.

3. By 2100, projected total repair costs for EU Member States amount to approximately EUR 76 billion under RCP4.5 and EUR 883 billion under RCP8.5, with the most affected countries varying between the scenarios. Italy, Portugal, Spain and Denmark would have to afford the highest total repair costs under RCP4.5. Under the severe RCP8.5 scenario, Poland, France, Germany, and Czechia would face the highest total repair costs.

<footnote n="19">¹⁹ IPCC, 2023: Summary for Policymakers. In: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, pp. 1-34, doi: 10.59327/IPCC/AR6-9789291691647.00</footnote>

<footnote n="20">²⁰ 5th Assessment Report of Intergovernmental Panel on Climate Change (2013)</footnote>

<footnote n="21">²¹ https://www.euro-cordex.net/</footnote>

<footnote n="22">²² http://jeodpp.jrc.ec.europa.eu/ftp/jrc-opendata/LISCOAST/10011/LATEST/</footnote>
4. Corrosion processes in the buildings built before the year 2000 are expected to initiate around 2050 under the extreme RCP8.5 scenario and after 2060 under RCP4.5. After corrosion initiation, corroded bars shall be cleaned but not replaced, and the polluted concrete cover shall be repaired.

5. Buildings in capital cities in north-eastern Europe exhibit similar carbonation depths to other EU capitals, but at lower temperatures, underscoring concrete durability's role in carbonation.

6. The welfare loss is measured as the annual repair cost-to-GDP ratio, with the highest impacts on GDP in Cyprus, Portugal, and Greece under RCP4.5 (0.12%, 0.11%, and 0.8% GDP, respectively), and Croatia, Czechia, and Poland under RCP8.5 (0.87%, 0.46% and 0.42% GDP, respectively).

7. Of the over 30 million concrete buildings considered, 14% may require repair by 2100 under RCP4.5, rising to 90% under RCP8.5. Poland, Germany, and Italy would be the most impacted in terms of the number of buildings requiring repair under RCP8.5.

8. The impacts of carbonation evaluated in this study are compatible with the climate change impacts evaluated by PESETA IV for no mitigation action (RCP8.5) and for the moderate mitigation concentration scenario (RCP4.5), and can enrich the impact categories of PESETA IV with the built environment.

<figure><img src="image_4.png" /><figcaption>IMPACT OF CLIMATE CHANGE INDUCED CARBONATION OF CONCRETE</figcaption></figure>
4. Corrosion processes in the buildings built before the year 2000 are expected to initiate around 2050 under the extreme RCP8.5 scenario and after 2060 under RCP4.5. After corrosion initiation, corroded bars shall be cleaned but not replaced, and the polluted concrete cover shall be repaired.

5. Buildings in capital cities in north-eastern Europe exhibit similar carbonation depths to other EU capitals, but at lower temperatures, underscoring concrete durability's role in carbonation.

6. The welfare loss is measured as the annual repair cost-to-GDP ratio, with the highest impacts on GDP in Cyprus, Portugal, and Greece under RCP4.5 (0.12%, 0.11%, and 0.8% GDP, respectively), and Croatia, Czechia, and Poland under RCP8.5 (0.87%, 0.46% and 0.42% GDP, respectively).

7. Of the over 30 million concrete buildings considered, 14% may require repair by 2100 under RCP4.5, rising to 90% under RCP8.5. Poland, Germany, and Italy would be the most impacted in terms of the number of buildings requiring repair under RCP8.5.

8. The impacts of carbonation evaluated in this study are compatible with the climate change impacts evaluated by PESETA IV for no mitigation action (RCP8.5) and for the moderate mitigation concentration scenario (RCP4.5), and can enrich the impact categories of PESETA IV with the built environment.

<figure><img src="image_5.png" /><figcaption>IMPACT OF CLIMATE CHANGE INDUCED CARBONATION OF CONCRETE</figcaption></figure>
## Policy Recommendations

This study underscores the significant economic and structural health challenges posed by climate change-induced carbonation and the urgent need for adaptive measures across the EU Member States. Recommendations include:

1. Developing and implementing guidance and regulations to reduce the effects of climate change-induced carbonation, and integrating adaptation strategies into building renovation and maintenance practices. The on-going renovation of the facades of the buildings to improve their energy efficiency provides a good opportunity to inspect the state of carbonation of the concrete and implement adaptive measures, where needed.

2. Encouraging adaptation strategies during the service life of existing buildings that include reparative actions for the damaged reinforced concrete, and protection measures against future corrosion.

3. Promoting the adoption of resilience-centric framework for new buildings, based on a dual approach: (i) design-phase adaptation measures based on the level of confidence we have in climate change predictions, and (ii) preventive maintenance strategy that evolves with climate change data.

4. Supporting refined assessments of repair costs for specific building categories or individual buildings, considering their unique features and local repair prices.

5. Advocating for assessments of climate change impacts on carbonation in reinforced concrete transport infrastructure.
## Policy Recommendations

This study underscores the significant economic and structural health challenges posed by climate change-induced carbonation and the urgent need for adaptive measures across the EU Member States. Recommendations include:

1. Developing and implementing guidance and regulations to reduce the effects of climate change-induced carbonation, and integrating adaptation strategies into building renovation and maintenance practices. The on-going renovation of the facades of the buildings to improve their energy efficiency provides a good opportunity to inspect the state of carbonation of the concrete and implement adaptive measures, where needed.

2. Encouraging adaptation strategies during the service life of existing buildings that include reparative actions for the damaged reinforced concrete, and protection measures against future corrosion.

3. Promoting the adoption of resilience-centric framework for new buildings, based on a dual approach: (i) design-phase adaptation measures based on the level of confidence we have in climate change predictions, and (ii) preventive maintenance strategy that evolves with climate change data.

4. Supporting refined assessments of repair costs for specific building categories or individual buildings, considering their unique features and local repair prices.

5. Advocating for assessments of climate change impacts on carbonation in reinforced concrete transport infrastructure.
# 1 Introduction

## 1.1 EU policy context and background

Climate change poses a significant threat to humans and ecosystems, with 3.3 to 3.6 billion people living in high sensitive climate change environments (IPCC, 2023²³). Development-constrained regions have high vulnerability to the impacts of the changing climate, with human mortality from floods, droughts, and storms being 15 times higher in highly vulnerable areas. Likewise, according to the Special Eurobarometer 538²⁴ released in May 2023, 77% of EU citizens consider climate change to be a major issue, with 4 to 10 of them personally exposed to its risks and concerns<fnref n="25" />.

Mitigation-related legislation and regulation initiatives addressing climate change have steadily increased over the past few years, as noted in the latest assessment by the Intergovernmental Panel on Climate Change (IPCC AR6, 2023²⁶). The risk of exceeding the 1.5°C warming threshold over the 21st century is getting higher, as demonstrated by the publication of the Nationally Determined Contributions (NDCs)<fnref n="27" />. These NDCs embody efforts by countries to reduce national emissions and adapt to the impacts of climate change, representing the projected global greenhouse gas (GHG) emissions for the year 2030. Planning and executing adaptation measures has evolved across all industries and geographical areas with proven benefits and varying degrees of effectiveness. However, despite advancements, there are still adaption gaps that will only widen at the current rates of adaptation measures deployment. Global warming will increase as long as greenhouse gas emissions are not reduced.

The EU aims to bridge the knowledge gap on climate change effects, climate adaptation benefits, and costs for effective climate policy development and implementation. Assessments of potential consequences of climate adaptation measures have been conducted on various sectors – i.e. agriculture, energy, river flooding, coastal floods, drought, habitat loss, forest fires, water, human impacts, forest ecosystems, and windstorms. Economic losses from climate-related extreme events are increasing, with an average annual loss of over EUR 12 billion. Exposure to global warming of 3°C above preindustrial levels would result in an annual loss of at least EUR 170 billion, 1.36% of the EU Gross domestic product (GDP) (JRC PESETA IV final report, 2020)<fnref n="28" />.

In the past years, the EU has launched numerous initiatives addressing and mitigating the impacts of the changing climate. Among these with a prominent role is the **European Green Deal**³ launched in 2019, outlining the EU's growth strategy for a sustainable future, with the aim of making Europe the world's first climate neutral continent by 2050, fully adapted to the unavoidable impacts of climate change. As part of the European Green Deal, the climate neutrality objective was enshrined in EU legislation with the publication of the **European Climate Law**, adopted in 2021 (Regulation (EU) 2021/1119²⁹). The legislation introduces the mandatory objective for the Member States and the EU for continuous progress in reducing climate change related vulnerabilities and increasing adaptive capacity. The goal of net zero balance of GHG emissions by 2050, and the intermediate target of reducing emissions by at least 55% by 2030, compared to 1990 levels, became legally binding in the EU with the European Climate Law.

In addition to global emission reduction commitments, the EU Climate Law recognises that Europe is experiencing adverse effects of climate change and major adaptation efforts are needed as an essential component of the overall long-term response to the climate crisis. A **new EU Adaptation Strategy to Climate**

<footnote n="23">²³ IPCC, 2023: Summary for Policymakers. In: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, pp. 1-34, doi: 10.59327/IPCC/AR6-9789291691647.00</footnote>

<footnote n="24">²⁴ Special Eurobarometer SP538: Climate Change, Directorate-General for Communication, https://europa.eu/eurobarometer/surveys/detail/2954 (accessed, 19.01.2024)</footnote>

<footnote n="25">²⁵ European Commission, Directorate-General for Climate Action, Climate change – Summary report, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/432566</footnote>

<footnote n="26">²⁶ IPCC, 2023: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, 184 pp., doi: 10.59327/IPCC/AR6-9789291691647</footnote>

<footnote n="27">²⁷ https://unfccc.int/process-and-meetings/the-paris-agreement/nationally-determined-contributions-ndcs</footnote>

<footnote n="28">²⁸ European Commission, Joint Research Centre, Feyen, L., Ciscar, J., Gosling, S. et al., Climate change impacts and adaptation in Europe – JRC PESETA IV final report, Ibarreta, D.(editor), Soria, A.(editor), Publications Office, 2020, https://data.europa.eu/doi/10.2760/171121</footnote>

<footnote n="29">²⁹ Regulation (EU) 2021/1119 of the European Parliament and of the Council of 30 June 2021 establishing the framework for achieving climate neutrality and amending Regulations (EC) No 401/2009 and (EU) 2018/1999 (‘European Climate Law’), https://eur-lex.europa.eu/eli/reg/2021/1119/oj</footnote>
# 1 Introduction

## 1.1 EU policy context and background

Climate change poses a significant threat to humans and ecosystems, with 3.3 to 3.6 billion people living in high sensitive climate change environments (IPCC, 2023²³). Development-constrained regions have high vulnerability to the impacts of the changing climate, with human mortality from floods, droughts, and storms being 15 times higher in highly vulnerable areas. Likewise, according to the Special Eurobarometer 538²⁴ released in May 2023, 77% of EU citizens consider climate change to be a major issue, with 4 to 10 of them personally exposed to its risks and concerns<fnref n="25" />.

Mitigation-related legislation and regulation initiatives addressing climate change have steadily increased over the past few years, as noted in the latest assessment by the Intergovernmental Panel on Climate Change (IPCC AR6, 2023²⁶). The risk of exceeding the 1.5°C warming threshold over the 21st century is getting higher, as demonstrated by the publication of the Nationally Determined Contributions (NDCs)<fnref n="27" />. These NDCs embody efforts by countries to reduce national emissions and adapt to the impacts of climate change, representing the projected global greenhouse gas (GHG) emissions for the year 2030. Planning and executing adaptation measures has evolved across all industries and geographical areas with proven benefits and varying degrees of effectiveness. However, despite advancements, there are still adaption gaps that will only widen at the current rates of adaptation measures deployment. Global warming will increase as long as greenhouse gas emissions are not reduced.

The EU aims to bridge the knowledge gap on climate change effects, climate adaptation benefits, and costs for effective climate policy development and implementation. Assessments of potential consequences of climate adaptation measures have been conducted on various sectors – i.e. agriculture, energy, river flooding, coastal floods, drought, habitat loss, forest fires, water, human impacts, forest ecosystems, and windstorms. Economic losses from climate-related extreme events are increasing, with an average annual loss of over EUR 12 billion. Exposure to global warming of 3°C above preindustrial levels would result in an annual loss of at least EUR 170 billion, 1.36% of the EU Gross domestic product (GDP) (JRC PESETA IV final report, 2020)<fnref n="28" />.

In the past years, the EU has launched numerous initiatives addressing and mitigating the impacts of the changing climate. Among these with a prominent role is the **European Green Deal**³ launched in 2019, outlining the EU's growth strategy for a sustainable future, with the aim of making Europe the world's first climate neutral continent by 2050, fully adapted to the unavoidable impacts of climate change. As part of the European Green Deal, the climate neutrality objective was enshrined in EU legislation with the publication of the **European Climate Law**, adopted in 2021 (Regulation (EU) 2021/1119²⁹). The legislation introduces the mandatory objective for the Member States and the EU for continuous progress in reducing climate change related vulnerabilities and increasing adaptive capacity. The goal of net zero balance of GHG emissions by 2050, and the intermediate target of reducing emissions by at least 55% by 2030, compared to 1990 levels, became legally binding in the EU with the European Climate Law.

In addition to global emission reduction commitments, the EU Climate Law recognises that Europe is experiencing adverse effects of climate change and major adaptation efforts are needed as an essential component of the overall long-term response to the climate crisis. A **new EU Adaptation Strategy to Climate**

<footnote n="23">²³ IPCC, 2023: Summary for Policymakers. In: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, pp. 1-34, doi: 10.59327/IPCC/AR6-9789291691647.00</footnote>

<footnote n="24">²⁴ Special Eurobarometer SP538: Climate Change, Directorate-General for Communication, https://europa.eu/eurobarometer/surveys/detail/2954 (accessed, 19.01.2024)</footnote>

<footnote n="25">²⁵ European Commission, Directorate-General for Climate Action, Climate change – Summary report, Publications Office of the European Union, 2023, https://data.europa.eu/doi/10.2834/432566</footnote>

<footnote n="26">²⁶ IPCC, 2023: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)]. IPCC, Geneva, Switzerland, 184 pp., doi: 10.59327/IPCC/AR6-9789291691647</footnote>

<footnote n="27">²⁷ https://unfccc.int/process-and-meetings/the-paris-agreement/nationally-determined-contributions-ndcs</footnote>

<footnote n="28">²⁸ European Commission, Joint Research Centre, Feyen, L., Ciscar, J., Gosling, S. et al., *Climate change impacts and adaptation in Europe – JRC PESETA IV final report*, Ibarreta, D.(editor), Soria, A.(editor), Publications Office, 2020, https://data.europa.eu/doi/10.2760/171121</footnote>

<footnote n="29">²⁹ Regulation (EU) 2021/1119 of the European Parliament and of the Council of 30 June 2021 establishing the framework for achieving climate neutrality and amending Regulations (EC) No 401/2009 and (EU) 2018/1999 (‘European Climate Law’), https://eur-lex.europa.eu/eli/reg/2021/1119/oj</footnote>
**Change (COM (2021) 82)**⁵ was therefore adopted in 2021, continuing along the path of the first adaptation strategy of 2013, to improve the adaptive capacity of the Member States and the Union, strengthen resilience and reduce vulnerability to climate change, in line with the global adaptation objective of Article 7 of the Paris Agreement<fnref n="30" />. Moreover, the new EU Strategy on Adaptation to Climate Change⁵ puts a stronger emphasis on the need for mainstreaming of climate adaptation in all levels and across different sectors of the economy, including the construction sector. It recognises the importance of increasing the preparedness of Europe's building stock to withstand the impacts of climate change, investing in climate-proof infrastructures, and updating standards governing the safety and performance of buildings and infrastructure in a changing climate.

The Strategy contains 49 actions at EU level spreading across four high-level objectives: smarter, more systemic, faster and international adaptation to climate change (SWD(2023) 339)⁶. Such climate adaptation actions bring synergies with other overarching policies and regulations that are part of the European Green Deal, such as the EU Climate Law but also the **Renovation Wave (COM(2020) 662 final)**⁷, and the **EU Strategy on Standardisation (COM(2022) 31 final)**¹², all of which contributing to developing a comprehensive EU policy framework addressing the climate resilience of buildings and infrastructure.

In particular, the Renovation Wave for Europe initiated by the European Commission to reach the objectives of climate neutrality for Europe by 2050 set by the European Green Deal will massively boost the renovation in the European built environment. The Renovation Wave addresses the twin challenge of energy efficiency and energy affordability, aiming to double, at least, the annual renovation rates of the building stock (currently being around 1%). Further, the Renovation Wave aims for the protection and adaptation of buildings to climate hazards such as high temperatures, floods, storms and many more.

Moreover, recognizing that the EU's ambition towards a climate neutral, resilient and circular economy cannot be delivered without leveraging the European standardisation system, the European Commission presented a new Standardisation Strategy to enable global leadership of EU standards in promoting values and a resilient, green and digital Single Market. The Strategy spots standards as '*the silent foundation of the EU Single Market and global competitiveness*', since they are '*invisible but a fundamental part of our daily life*'.

European standards are embedded in the EU policy objectives and have a key role in achieving a climate-neutral, resilient and circular economy.

Other complementary initiatives published in recent years facilitate the implementation of the EU Green Deal within the construction sector, for example the **New Circular Economy Action Plan (COM(2020)98)**<fnref n="31" />, the **new European Bauhaus (COM(2021) 573 final)**⁸, the **Sustainable Finance Taxonomy**<fnref n="32" />, the **Green Public Procurement**<fnref n="33" /> criteria for public buildings, the proposals for recasting the **Energy Performance of Buildings Directive (EPBD) (COM/2021/802 final)**<fnref n="34" />, the **revision of the Construction Products Regulation (CPR)**<fnref n="35" />, the **EU Mission on Adaptation to Climate change**<fnref n="36" /> as part of Horizon Europe framework programme, the

<footnote n="30">³⁰ Paris Agreement, United Nations 2015, https://unfccc.int/sites/default/files/english_paris_agreement.pdf. Art. 6 (pp. 7-8); Art. 7 (pp. 9-11); Art. 12 (p. 16)</footnote>

<footnote n="31">³¹ European Commission (2020). *A New Circular Economy Action Plan for a Cleaner and More Competitive Europe*, COM(2020) 98</footnote>

<footnote n="32">³² OJ L 198, 22.6.2020, p. 13-43, *Taxonomy Regulation 2020/852/EU*. Regulation (EU) 2020/852 of the European Parliament and of the Council of 18 June 2020 on the establishment of a framework to facilitate sustainable investment, and amending Regulation (EU) 2019/2088 (Text with EEA relevance) PE/20/2020/INIT, OJ L 198, 22.6.2020, p. 13-43, http://data.europa.eu/eli/reg/2020/852/oj</footnote>

<footnote n="33">³³ COM/2008/0400 final, *Public procurement for a better environment*, European Commission (2008). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions Public procurement for a better environment (SEC(2008) 2124) (SEC(2008) 2125) (SEC(2008) 2126) /* COM/2008/0400 final */, Brussels, 16.7.2008</footnote>

<footnote n="34">³⁴ Amendments adopted by the European Parliament on 14 March 2023 on the proposal for a directive of the European Parliament and of the Council on the energy performance of buildings (recast) (COM(2021)0802 – C9-0469/2021 – 2021/0426(COD)), European Parliament, Tuesday, 14 March 2023 – Strasbourg, https://www.europarl.europa.eu/doceo/document/TA-9-2023-0068_EN.html#title2</footnote>

<footnote n="35">³⁵ Proposal for a Regulation laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011; COM(2022) 144 - Proposal for a Regulation laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011 and COM(2022) 144 ANNEX - Annex to the Proposal</footnote>

<footnote n="36">³⁶https://research-and-innovation.ec.europa.eu/funding/funding-opportunities/funding-programmes-and-open-calls/horizon-europe/eu-missions-horizon-europe/adaptation-climate-change_en</footnote>
**Change (COM (2021) 82)**⁵ was therefore adopted in 2021, continuing along the path of the first adaptation strategy of 2013, to improve the adaptive capacity of the Member States and the Union, strengthen resilience and reduce vulnerability to climate change, in line with the global adaptation objective of Article 7 of the Paris Agreement<fnref n="30" />. Moreover, the new EU Strategy on Adaptation to Climate Change⁵ puts a stronger emphasis on the need for mainstreaming of climate adaptation in all levels and across different sectors of the economy, including the construction sector. It recognises the importance of increasing the preparedness of Europe's building stock to withstand the impacts of climate change, investing in climate-proof infrastructures, and updating standards governing the safety and performance of buildings and infrastructure in a changing climate.

The Strategy contains 49 actions at EU level spreading across four high-level objectives: smarter, more systemic, faster and international adaptation to climate change (SWD(2023) 339)⁶. Such climate adaptation actions bring synergies with other overarching policies and regulations that are part of the European Green Deal, such as the EU Climate Law but also the **Renovation Wave (COM(2020) 662 final)**⁷, and the **EU Strategy on Standardisation (COM(2022) 31 final)**¹², all of which contributing to developing a comprehensive EU policy framework addressing the climate resilience of buildings and infrastructure.

In particular, the Renovation Wave for Europe initiated by the European Commission to reach the objectives of climate neutrality for Europe by 2050 set by the European Green Deal will massively boost the renovation in the European built environment. The Renovation Wave addresses the twin challenge of energy efficiency and energy affordability, aiming to double, at least, the annual renovation rates of the building stock (currently being around 1%). Further, the Renovation Wave aims for the protection and adaptation of buildings to climate hazards such as high temperatures, floods, storms and many more.

Moreover, recognizing that the EU's ambition towards a climate neutral, resilient and circular economy cannot be delivered without leveraging the European standardisation system, the European Commission presented a new Standardisation Strategy to enable global leadership of EU standards in promoting values and a resilient, green and digital Single Market. The Strategy spots standards as '*the silent foundation of the EU Single Market and global competitiveness*', since they are '*invisible but a fundamental part of our daily life*'.

European standards are embedded in the EU policy objectives and have a key role in achieving a climate-neutral, resilient and circular economy.

Other complementary initiatives published in recent years facilitate the implementation of the EU Green Deal within the construction sector, for example the **New Circular Economy Action Plan (COM(2020)98)**<fnref n="31" />, the **new European Bauhaus (COM(2021) 573 final)**⁸, the **Sustainable Finance Taxonomy**<fnref n="32" />, the **Green Public Procurement**<fnref n="33" /> criteria for public buildings, the proposals for recasting the **Energy Performance of Buildings Directive (EPBD) (COM/2021/802 final)**<fnref n="34" />, the **revision of the Construction Products Regulation (CPR)**<fnref n="35" />, the **EU Mission on Adaptation to Climate change**<fnref n="36" /> as part of Horizon Europe framework programme, the

<footnote n="30">³⁰ Paris Agreement, United Nations 2015, https://unfccc.int/sites/default/files/english_paris_agreement.pdf. Art. 6 (pp. 7-8); Art. 7 (pp. 9-11); Art. 12 (p. 16)</footnote>

<footnote n="31">³¹ European Commission (2020). *A New Circular Economy Action Plan for a Cleaner and More Competitive Europe*, COM(2020) 98</footnote>

<footnote n="32">³² OJ L 198, 22.6.2020, p. 13–43, *Taxonomy Regulation 2020/852/EU*. Regulation (EU) 2020/852 of the European Parliament and of the Council of 18 June 2020 on the establishment of a framework to facilitate sustainable investment, and amending Regulation (EU) 2019/2088 (Text with EEA relevance) PE/20/2020/INIT, OJ L 198, 22.6.2020, p. 13–43, http://data.europa.eu/eli/reg/2020/852/oj</footnote>

<footnote n="33">³³ COM/2008/0400 final, *Public procurement for a better environment*, European Commission (2008). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions Public procurement for a better environment (SEC(2008) 2124) (SEC(2008) 2125) (SEC(2008) 2126) /* COM/2008/0400 final */, Brussels, 16.7.2008</footnote>

<footnote n="34">³⁴ Amendments adopted by the European Parliament on 14 March 2023 on the proposal for a directive of the European Parliament and of the Council on the energy performance of buildings (recast) (COM(2021)0802 – C9-0469/2021 – 2021/0426(COD)), European Parliament, Tuesday, 14 March 2023 – Strasbourg, https://www.europarl.europa.eu/doceo/document/TA-9-2023-0068_EN.html#title2</footnote>

<footnote n="35">³⁵ Proposal for a Regulation laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011; COM(2022) 144 - Proposal for a Regulation laying down harmonised conditions for the marketing of construction products, amending Regulation (EU) 2019/1020 and repealing Regulation (EU) 305/2011 and COM(2022) 144 ANNEX - Annex to the Proposal</footnote>

<footnote n="36">³⁶https://research-and-innovation.ec.europa.eu/funding/funding-opportunities/funding-programmes-and-open-calls/horizon-europe/eu-missions-horizon-europe/adaptation-climate-change_en</footnote>
Level(s) framework for Sustainable Buildings<fnref n="37" />, and the Digital Buildings logbook (Dourlens-Quaranta et al. 2021)<fnref n="38" />.

In particular, the EU Missions (COM(2021) 609 final<fnref n="39" />) is a novelty of the Horizon Europe<fnref n="40" /> research and innovation programme, launched in September 2021 and intends to assist 150 European regions in becoming climate-resilient by 2030. It aims to contribute to systemic policymaking based on Research and Innovation (R&I) data, speed adaptation to climate change, and spark transformative change in Europe. The EU Missions place significant emphasis on various goals, such as raising awareness about climate change, understanding local risks and impacts, developing effective governance structures, mobilizing European regions and communities to adapt and become climate resilient by 2030, supporting cities in achieving smart and climate-neutral status by 2030, and creating strategic frameworks for implementing pilot and transformative actions.

The EU's Horizon Europe funding programme identifies five mission areas to effectively address climate change adaptation as part of a mission-based public policy across Europe. Two of these mission areas, related to the construction industry, are namely: **Adaptation to Climate Change**<fnref n="41" /> and **100 Climate-Neutral and Smart Cities by 2030**<fnref n="42" />. Many cities support the EU Missions' objectives to establish 100 smart and climate-neutral cities by 2030 and serve as test sites for all EU cities to attain climate neutrality by 2050. EU Missions, in collaboration with the European Commission's Joint Research Centre (JRC) and EIT Climate-KIC<fnref n="43" />, are providing direct support and evidence-based knowledge to regions and local authorities in three areas: understanding climate risks, defining pathways to climate resilience, and building resilience through large-scale demonstration projects.

The estimated built-up area in Europe, encompassing both residential and non-residential segments in the EU27, Switzerland, and Norway, spans an impressive 25 billion square meters. Residential buildings, including single-family homes (SFHs) and multi-family homes (MFHs), represent the most prevalent construction segment in Europe. In fact, nearly all dwellings in Europe, accounting for 98.5% in the EU-27, are located within residential buildings (Gkatzogias et al., 2023⁴⁴; Romano et al., 2023⁴⁵). A significant majority, approximately 79%, of the European dwellings were built before 1990 and do not comply with modern energy efficiency provisions or seismic design requirements, with more than 20% constructed before 1945 (REEBUILD project<fnref n="46" />). As noted by experts (Wang et al., 2014⁴⁷), even minor increases in maintenance and repair costs resulting from climate change can have substantial economic consequences on a global scale. In light of these facts, it becomes evident that urgent action is needed to address the challenges posed in the existing building stock in Europe.

Moreover, the distinctive blend of antique and modern architecture in the European building stock presents both substantial potential but also problems since 75% of the Union's building stock has a poor energy performance

<footnote n="37">³⁷ European Commission, Level(s) European framework for sustainable buildings, The Level(s) framework was officially launched on 15 October 2020, Level(s) Specimen Specialised Article For Public Authorities and Decision-Maker.pdf</footnote>

<footnote n="38">³⁸ European Commission, Executive Agency for Small and Medium-sized Enterprises, Dourlens-Quaranta, S., Carbonar, G., De Groote, M. et al., 'Study on the development of a European Union framework for digital building logbooks - Final report', Publications Office, 2021, https://data.europa.eu/doi/10.2826/659006</footnote>

<footnote n="39">³⁹ European Commission (2021). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions on European Missions, Brussels, 29.9.2021, COM(2021) 609 final</footnote>

<footnote n="40">⁴⁰ Regulation (EU) 2021/695 of the European Parliament and of the Council of 28 April 2021 establishing Horizon Europe, Recital 2</footnote>

<footnote n="41">⁴¹ European Commission, Directorate-General for Research and Innovation, Hedegaard, C., Mysiak, J., Lera St. Clair, A. et al., A climate resilient Europe - Prepare Europe for climate disruptions and accelerate the transformation to a climate resilient and just Europe by 2030, Publications Office, 2020, https://data.europa.eu/doi/10.2777/69766</footnote>

<footnote n="42">⁴² European Commission, Directorate-General for Research and Innovation, Gronkiewicz-Waltz, H., Larsson, A., Boni, A. et al., 100 climate-neutral cities by 2030 - by and for the citizens - Report of the mission board for climate-neutral and smart cities, Publications Office, 2020, https://data.europa.eu/doi/10.2777/46063</footnote>

<footnote n="43">⁴³ EIT Climate-KIC, supported by the European Institute of Innovation and Technology, is a Knowledge and Innovation Community (KIC), working to accelerate the transition to a zero-carbon, climate-resilient society, https://www.climate-kic.org/who-we-are/what-is-climate-kic/</footnote>

<footnote n="44">⁴⁴ Gkatzogias, K., Pohoryles, D., Romano, E., Bournas, D., Negro, P., Tsionis, G. and Dimova, S., 'Integrated seismic and energy renovation of buildings', EUR 31465 EN, Publications Office of the European Union, Luxembourg, 2023, ISBN 978-92-68-01355-7, doi:10.2760/346428, JRC132940.</footnote>

<footnote n="45">⁴⁵ Romano, E., Negro, P., Santarsiero, G., Masi, A. and Butenweg, C., 'Identification of European buildings most needing seismic and energy retrofit with a focus on the Italian context', Romano, E. and Negro, P. editor(s), Publications Office of the European Union, Luxembourg, 2023, doi:10.2760/30640, JRC130997.</footnote>

<footnote n="46">⁴⁶ Data from the pilot project 'Integrated techniques for the seismic strengthening and energy efficiency of existing buildings' or REEBUILD, financed by the European Union under the Commission Decision under the Commission Decision C(2019) 3874 final of 28 May 2019.</footnote>

<footnote n="47">⁴⁷ Wang, Q., Wei, J., Dong, R., and Xu G., 'Numerical analysis of carbonation process for concrete structures', Journal of Wuhan University of Technology, vol. 36, no. 5, 2014, pp. 91-96.</footnote>
Level(s) framework for Sustainable Buildings<fnref n="37" />, and the Digital Buildings logbook (Dourlens-Quaranta et al. 2021)<fnref n="38" />.

In particular, the EU Missions (COM(2021) 609 final<fnref n="39" />) is a novelty of the Horizon Europe<fnref n="40" /> research and innovation programme, launched in September 2021 and intends to assist 150 European regions in becoming climate-resilient by 2030. It aims to contribute to systemic policymaking based on Research and Innovation (R&I) data, speed adaptation to climate change, and spark transformative change in Europe. The EU Missions place significant emphasis on various goals, such as raising awareness about climate change, understanding local risks and impacts, developing effective governance structures, mobilizing European regions and communities to adapt and become climate resilient by 2030, supporting cities in achieving smart and climate-neutral status by 2030, and creating strategic frameworks for implementing pilot and transformative actions.

The EU's Horizon Europe funding programme identifies five mission areas to effectively address climate change adaptation as part of a mission-based public policy across Europe. Two of these mission areas, related to the construction industry, are namely: **Adaptation to Climate Change**<fnref n="41" /> and **100 Climate-Neutral and Smart Cities by 2030**<fnref n="42" />. Many cities support the EU Missions' objectives to establish 100 smart and climate-neutral cities by 2030 and serve as test sites for all EU cities to attain climate neutrality by 2050. EU Missions, in collaboration with the European Commission's Joint Research Centre (JRC) and EIT Climate-KIC<fnref n="43" />, are providing direct support and evidence-based knowledge to regions and local authorities in three areas: understanding climate risks, defining pathways to climate resilience, and building resilience through large-scale demonstration projects.

The estimated built-up area in Europe, encompassing both residential and non-residential segments in the EU27, Switzerland, and Norway, spans an impressive 25 billion square meters. Residential buildings, including single-family homes (SFHs) and multi-family homes (MFHs), represent the most prevalent construction segment in Europe. In fact, nearly all dwellings in Europe, accounting for 98.5% in the EU-27, are located within residential buildings (Gkatzogias et al., 2023⁴⁴; Romano et al., 2023⁴⁵). A significant majority, approximately 79%, of the European dwellings were built before 1990 and do not comply with modern energy efficiency provisions or seismic design requirements, with more than 20% constructed before 1945 (REEBUILD project<fnref n="46" />). As noted by experts (Wang et al., 2014⁴⁷), even minor increases in maintenance and repair costs resulting from climate change can have substantial economic consequences on a global scale. In light of these facts, it becomes evident that urgent action is needed to address the challenges posed in the existing building stock in Europe.

Moreover, the distinctive blend of antique and modern architecture in the European building stock presents both substantial potential but also problems since 75% of the Union's building stock has a poor energy performance

<footnote n="37">³⁷ European Commission, Level(s) European framework for sustainable buildings, The Level(s) framework was officially launched on 15 October 2020, Level(s) Specimen Specialised Article For Public Authorities and Decision-Maker.pdf</footnote>

<footnote n="38">³⁸ European Commission, Executive Agency for Small and Medium-sized Enterprises, Dourlens-Quaranta, S., Carbonar, G., De Groote, M. et al., 'Study on the development of a European Union framework for digital building logbooks - Final report', Publications Office, 2021, https://data.europa.eu/doi/10.2826/659006</footnote>

<footnote n="39">³⁹ European Commission (2021). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions on European Missions, Brussels, 29.9.2021, COM(2021) 609 final</footnote>

<footnote n="40">⁴⁰ Regulation (EU) 2021/695 of the European Parliament and of the Council of 28 April 2021 establishing Horizon Europe, Recital 2</footnote>

<footnote n="41">⁴¹ European Commission, Directorate-General for Research and Innovation, Hedegaard, C., Mysiak, J., Lera St. Clair, A. et al., A climate resilient Europe - Prepare Europe for climate disruptions and accelerate the transformation to a climate resilient and just Europe by 2030, Publications Office, 2020, https://data.europa.eu/doi/10.2777/69766</footnote>

<footnote n="42">⁴² European Commission, Directorate-General for Research and Innovation, Gronkiewicz-Waltz, H., Larsson, A., Boni, A. et al., 100 climate-neutral cities by 2030 - by and for the citizens - Report of the mission board for climate-neutral and smart cities, Publications Office, 2020, https://data.europa.eu/doi/10.2777/46063</footnote>

<footnote n="43">⁴³ EIT Climate-KIC, supported by the European Institute of Innovation and Technology, is a Knowledge and Innovation Community (KIC), working to accelerate the transition to a zero-carbon, climate-resilient society, https://www.climate-kic.org/who-we-are/what-is-climate-kic/</footnote>

<footnote n="44">⁴⁴ Gkatzogias, K., Pohoryles, D., Romano, E., Bournas, D., Negro, P., Tsionis, G. and Dimova, S., 'Integrated seismic and energy renovation of buildings', EUR 31465 EN, Publications Office of the European Union, Luxembourg, 2023, ISBN 978-92-68-01355-7, doi:10.2760/346428, JRC132940.</footnote>

<footnote n="45">⁴⁵ Romano, E., Negro, P., Santarsiero, G., Masi, A. and Butenweg, C., 'Identification of European buildings most needing seismic and energy retrofit with a focus on the Italian context', Romano, E. and Negro, P. editor(s), Publications Office of the European Union, Luxembourg, 2023, doi:10.2760/30640, JRC130997.</footnote>

<footnote n="46">⁴⁶ Data from the pilot project 'Integrated techniques for the seismic strengthening and energy efficiency of existing buildings' or REEBUILD, financed by the European Union under the Commission Decision under the Commission Decision C(2019) 3874 final of 28 May 2019.</footnote>

<footnote n="47">⁴⁷ Wang, Q., Wei J., Dong R., and Xu G., 'Numerical analysis of carbonation process for concrete structures', Journal of Wuhan University of Technology, vol. 36, no. 5, 2014, pp. 91-96.</footnote>
(Filippidou et al., 2019⁴⁸). The **revision** (recast) of the **Energy Performance of Buildings Directive** (EPBD) 2018/844³⁴ aims to set the EU firmly on the path towards net zero GHG emissions (climate neutrality) by 2050, including accelerating building renovation rates and promoting the uptake of renewable energy in buildings. A provisional agreement between the Parliament and the Council was reached on December 2023⁴⁹ stating that all new buildings should be zero-emission as of 2030.

Member States can implement their renovation plans using Union funding and financing mechanisms, specifically under the **InvestEU programme**<fnref n="50" />. This includes utilizing various funding mechanisms such as the **Resilience and Recovery Instrument**<fnref n="51" />, the **Structural European Regional Development Fund and Cohesion Fund**<fnref n="52" />, and the **Climate Social Fund**<fnref n="53" /> to finance the implementation of building renovation plans and contribute to achieving the green transition.

The recast of the **Energy Efficiency Directive** (EED) in July 2023 (PE 15 2023 INIT<fnref n="54" />, 2023) requires Member States to create energy savings requirements, including building renovation measures, to alleviate and avoid energy poverty. The EU is prioritizing the **energy efficiency first principle**<fnref n="55" /> to reduce final energy consumption by 11.7% by 2030 compared to 2020. To achieve the 32.5% energy efficiency target, the EU must propose a strategy for addressing buildings' energy from 2021 to 2030 through integrated national energy and climate plans (NECPs)<fnref n="56" /> and long-term building renovation strategies (LTRS)<fnref n="57" /> by each EU country. The EU is aiming to revamp Europe's building stock to combat climate change, and this objective is strongly supported by the construction sector, which views renovation as a business opportunity.

In alignment with this goal, the EU has introduced a comprehensive policy that includes the New European Bauhaus initiative. This initiative aims to promote the environmental sustainability of building solutions and materials, revise the Construction Products Regulation, and establish measures to enhance reuse, recycling, efficient resource management, better performing materials and digital tools. The overarching objective is to reduce the environmental impact of buildings and their footprint. Additionally, these initiatives focus not only on improving buildings' resilience to climate-related hazards such as temperature, wind, water, and soil, but also on ensuring the well-being, health, safety, and security standards of occupants are met.

Considering that infrastructures have a long service life and most buildings have a longer service life than their design working life, it is fundamental that they are made more climate resilient over their lifetime, starting in the design, but also in maintenance and renovation stages (Wang et al., 2014). The design, construction, and retrofitting of housing should consider climate risk information, according to the Intergovernmental Panel on Climate Change (IPCC, 2023) to maintain safe and resilient buildings. In order to assess the potential effects of climate change methodology on buildings, fundamental components of climate vulnerability and risk assessments (CVRAs) are specified in the IPCC AR6 2023 report. It recommends a doable, progressive strategy for carrying out these assessments, which includes determining exposure, vulnerability, and potential effects. These assessments cover physical hazards, environmental factors, sensitivity, adaptive capacity, and impacts, ensuring that climate-related risks are assessed and mitigated.

<footnote n="48">⁴⁸ Filippidou, F. and Jimenez Navarro, J., 'Achieving the cost-effective energy transformation of Europe's buildings', EUR 29906 EN, Publications Office of the European Union, Luxembourg, 2019, ISBN 978-92-76-12394-1, doi:10.2760/278207, JRC117739.</footnote>

<footnote n="49">⁴⁹ ST 16655 2023 INIT – NOTE. Interinstitutional File: 2021/0426(COD), ‘Proposal for a DIRECTIVE OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on the energy performance of buildings (recast) – Analysis of the final compromise text with a view to agreement’, General Secretariat of the Council, Brussels, 14 December 2023, https://data.consilium.europa.eu/doc/document/ST-16655-2023-INIT/en/pdf</footnote>

<footnote n="50">⁵⁰ InvestEU programme, https://investeu.europa.eu/index_en</footnote>

<footnote n="51">⁵¹ OJ L 57, 18.2.2021, p. 17. Regulation (EU) 2021/241 of the European Parliament and of the Council of 12 February 2021 establishing the Recovery and Resilience Facility.</footnote>

<footnote n="52">⁵² OJ L 231, 30.6.2021, p. 60–93. Regulation (EU) 2021/1058 of the European Parliament and of the Council of 24 June 2021 on the European Regional Development Fund and on the Cohesion Fund, PE/48/2021/INIT, http://data.europa.eu/eli/reg/2021/1058/oj</footnote>

<footnote n="53">⁵³ OJ L 130, 16.5.2023, p. 1–51. Regulation (EU) 2023/955 of the European Parliament and of the Council of 10 May 2023 establishing a Social Climate Fund and amending Regulation (EU) 2021/1060, PE/11/2023/REV/1, http://data.europa.eu/eli/reg/2023/955/oj</footnote>

<footnote n="54">⁵⁴ DIRECTIVE OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on energy efficiency and amending Regulation (EU) 2023/955 (recast), PE 15 2023 INIT, European Union, The European Parliament and The Council, Brussels, 13 July 2023, https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CONSI%，%3APE_15_2023_INIT&qid=1691999531020</footnote>

<footnote n="55">⁵⁵ Commission Recommendation (EU) 2021/1749 of 28 September 2021 on Energy Efficiency First: from principles to practice — Guidelines and examples for its implementation in decision-making in the energy sector and beyond, C/2021/7014</footnote>

<footnote n="56">⁵⁶ https://commission.europa.eu/energy-climate-change-environment/implementation-eu-countries/energy-and-climate-governance-and-reporting/national-energy-and-climate-plans_en</footnote>

<footnote n="57">⁵⁷ https://ec.europa.eu/info/energy-climate-change-environment/implementation-eu-countries/energy-and-climate-governance-and-reporting/national-long-term-strategies_en</footnote>
(Filippidou et al., 2019⁴⁸). The **revision** (recast) of the **Energy Performance of Buildings Directive** (EPBD) 2018/844³⁴ aims to set the EU firmly on the path towards net zero GHG emissions (climate neutrality) by 2050, including accelerating building renovation rates and promoting the uptake of renewable energy in buildings. A provisional agreement between the Parliament and the Council was reached on December 2023⁴⁹ stating that all new buildings should be zero-emission as of 2030.

Member States can implement their renovation plans using Union funding and financing mechanisms, specifically under the **InvestEU programme**<fnref n="50" />. This includes utilizing various funding mechanisms such as the **Resilience and Recovery Instrument**<fnref n="51" />, the **Structural European Regional Development Fund and Cohesion Fund**<fnref n="52" />, and the **Climate Social Fund**<fnref n="53" /> to finance the implementation of building renovation plans and contribute to achieving the green transition.

The recast of the **Energy Efficiency Directive** (EED) in July 2023 (PE 15 2023 INIT<fnref n="54" />, 2023) requires Member States to create energy savings requirements, including building renovation measures, to alleviate and avoid energy poverty. The EU is prioritizing the **energy efficiency first principle**<fnref n="55" /> to reduce final energy consumption by 11.7% by 2030 compared to 2020. To achieve the 32.5% energy efficiency target, the EU must propose a strategy for addressing buildings' energy from 2021 to 2030 through integrated national energy and climate plans (NECPs)<fnref n="56" /> and long-term building renovation strategies (LTRS)<fnref n="57" /> by each EU country. The EU is aiming to revamp Europe's building stock to combat climate change, and this objective is strongly supported by the construction sector, which views renovation as a business opportunity.

In alignment with this goal, the EU has introduced a comprehensive policy that includes the New European Bauhaus initiative. This initiative aims to promote the environmental sustainability of building solutions and materials, revise the Construction Products Regulation, and establish measures to enhance reuse, recycling, efficient resource management, better performing materials and digital tools. The overarching objective is to reduce the environmental impact of buildings and their footprint. Additionally, these initiatives focus not only on improving buildings' resilience to climate-related hazards such as temperature, wind, water, and soil, but also on ensuring the well-being, health, safety, and security standards of occupants are met.

Considering that infrastructures have a long service life and most buildings have a longer service life than their design working life, it is fundamental that they are made more climate resilient over their lifetime, starting in the design, but also in maintenance and renovation stages (Wang et al., 2014). The design, construction, and retrofitting of housing should consider climate risk information, according to the Intergovernmental Panel on Climate Change (IPCC, 2023) to maintain safe and resilient buildings. In order to assess the potential effects of climate change methodology on buildings, fundamental components of climate vulnerability and risk assessments (CVRAs) are specified in the IPCC AR6 2023 report. It recommends a doable, progressive strategy for carrying out these assessments, which includes determining exposure, vulnerability, and potential effects. These assessments cover physical hazards, environmental factors, sensitivity, adaptive capacity, and impacts, ensuring that climate-related risks are assessed and mitigated.

<footnote n="48">⁴⁸ Filippidou, F. and Jimenez Navarro, J., 'Achieving the cost-effective energy transformation of Europe's buildings', EUR 29906 EN, Publications Office of the European Union, Luxembourg, 2019, ISBN 978-92-76-12394-1, doi:10.2760/278207, JRC117739.</footnote>

<footnote n="49">⁴⁹ ST 16655 2023 INIT – NOTE. Interinstitutional File: 2021/0426(COD), ‘Proposal for a DIRECTIVE OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on the energy performance of buildings (recast) – Analysis of the final compromise text with a view to agreement’, General Secretariat of the Council, Brussels, 14 December 2023, https://data.consilium.europa.eu/doc/document/ST-16655-2023-INIT/en/pdf</footnote>

<footnote n="50">⁵⁰ InvestEU programme, https://investeu.europa.eu/index_en</footnote>

<footnote n="51">⁵¹ OJ L 57, 18.2.2021, p. 17. Regulation (EU) 2021/241 of the European Parliament and of the Council of 12 February 2021 establishing the Recovery and Resilience Facility.</footnote>

<footnote n="52">⁵² OJ L 231, 30.6.2021, p. 60–93. Regulation (EU) 2021/1058 of the European Parliament and of the Council of 24 June 2021 on the European Regional Development Fund and on the Cohesion Fund, PE/48/2021/INIT, http://data.europa.eu/eli/reg/2021/1058/oj</footnote>

<footnote n="53">⁵³ OJ L 130, 16.5.2023, p. 1–51. Regulation (EU) 2023/955 of the European Parliament and of the Council of 10 May 2023 establishing a Social Climate Fund and amending Regulation (EU) 2021/1060, PE/11/2023/REV/1, http://data.europa.eu/eli/reg/2023/955/oj</footnote>

<footnote n="54">⁵⁴ DIRECTIVE OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on energy efficiency and amending Regulation (EU) 2023/955 (recast), PE 15 2023 INIT, European Union, The European Parliament and The Council, Brussels, 13 July 2023, https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CONSI%，%3APE_15_2023_INIT&qid=1691999531020</footnote>

<footnote n="55">⁵⁵ Commission Recommendation (EU) 2021/1749 of 28 September 2021 on Energy Efficiency First: from principles to practice — Guidelines and examples for its implementation in decision-making in the energy sector and beyond, C/2021/7014</footnote>

<footnote n="56">⁵⁶ https://commission.europa.eu/energy-climate-change-environment/implementation-eu-countries/energy-and-climate-governance-and-reporting/national-energy-and-climate-plans_en</footnote>

<footnote n="57">⁵⁷ https://ec.europa.eu/info/energy-climate-change-environment/implementation-eu-countries/energy-and-climate-governance-and-reporting/national-long-term-strategies_en</footnote>
The scenarios for a transition pathway for a greener, more digital and resilient construction (SWD (2021) 419)<fnref n="58" /> provide a vision on the needs for faster recovery from the pandemic and increasing the resilience of the construction industrial ecosystem. Among the priority actions is the enhancement of safety, sustainability and climate resilience in the built environment in the context of the upgrade of the European standards for the design of structures (i.e the EN Eurocodes: EN 1990 to EN 1999⁵⁹) and other relevant building standards.

The **new technical guidance on climate proofing of infrastructure in the period 2021-2027**<fnref n="60" /> sets out common principles, requirements and practices to deal with physical climate risks in major infrastructure projects - e.g., funded by the **European Regional Development Fund**<fnref n="61" />. To note that the term infrastructure in this guidance refers to buildings, network infrastructure, and a range of built systems and assets. The guidance rests on two pillars: mitigation and climate neutrality as well as adaptation and climate resilience. The EN Eurocodes are referenced as a tool for climate proofing of infrastructure.

Many climatic variables, and their extension into future climate change projections, are likely to have an impact on the safety of buildings and constructions. Indeed, buildings are threatened over their lifetime by a number of climate hazards, including the augment of temperature, frequency and magnitude of extreme weather events, river flooding or sea level rise, trends of acidity rainfall, etc., which might accelerate the degradation of construction materials and compromise their durability, particularly when they have not been designed to take account for future climatic conditions. Resilient structures must anticipate, prepare for, and adapt to changing climatic conditions, react quickly, and recover quickly. They should significantly reduce climate risks for themselves, occupants, environment, and assets by minimizing adverse effects on their components.

## 1.2 JRC activities in support of adaptation of structural design to climate change

Numerous policies and initiatives referenced previously in Sub-section 1.1 will impact the building sector development and the construction market evolution and capacity for adaptation to climate challenges in the future. Climate change significantly impacts buildings in Europe, causing heat waves, storms, heavy precipitation, and flooding events. To address these increasing numbers of hazards, effective adaptation measures must be resilient to multiple hazards. Technical guidance on climate-adaptation measures is needed for both new and existing buildings across different climatic zones. Solutions should reduce climate risks with involved stakeholders being oriented to improve building performance.

In 2022, the Commission and the European Environment Agency initiated the preparation of the **first European Climate Risk Assessment** (EUCRA)<fnref n="62" />. This independent scientific report will assess current and future climate change impacts and risks relating to the environment, economy and wider society in Europe. The assessment will also address cross-border, cascading and compound risks. It will also address key actions to mitigate the climate risk for infrastructure, focussing on transport and energy networks, buildings (as regards the design and standards), and water use and management infrastructure. Publication of the report is foreseen for 2024.

The Commission action plan for implementing the New EU Strategy on Adaptation to Climate Change (COM (2021) 82)⁵ includes activities in support to integration of climate resilience considerations into the criteria applicable to construction and renovation of buildings and critical infrastructure. Along this line, the Commission integrated climate resilience in its December 2021 proposal for the revision of the Energy Performance of Buildings Directive (EPBD), which will make it mandatory for Member States to address climate change adaptation for both new and existing buildings. Moreover, the Commission put forward provisions to inform about the performance of construction products also under future climate in its March 2022 proposal for the revision of the Construction Products Regulation. Among the other activities to be performed by the Commission, the **Report on the Implementation of the EU Strategy on Adaptation to Climate Change** (SWD(2023) 339)⁶ mentions the Joint Research Centre (JRC) activities regarding the study on climate change induced corrosion, estimating the total repair costs of reinforced concrete buildings, as well as the JRC pilot studies on

<footnote n="58">⁵⁸ Commission Staff Working Paper (2021), Scenarios for a transition pathway for a greener, more digital and resilient construction ecosystem, SWD(2021) 419 final, https://ec.europa.eu/docsroom/documents/47996</footnote>

<footnote n="59">⁵⁹ https://eurocodes.jrc.ec.europa.eu/</footnote>

<footnote n="60">⁶⁰ COMMISSION NOTICE, 2021. Technical guidance on the climate proofing of infrastructure in the period 2021-2027 (2021/C 373/01)</footnote>

<footnote n="61">⁶¹ Regulation (EU) 2021/1058 of the European Parliament and of the Council of 24 June 2021 on the European Regional Development Fund and on the Cohesion Fund, PE/48/2021/INIT</footnote>

<footnote n="62">⁶² In May 2022, the Directorate-General for Climate Action of the European Commission (DG CLIMA) and the European Environment Agency (EEA) initiated the preparation of the first European Climate Risk Assessment (EUCRA). The EUCRA assesses current and future climate change impacts and risks relating to the environment, economy and wider society in Europe.</footnote>
The scenarios for a transition pathway for a greener, more digital and resilient construction (SWD (2021) 419)<fnref n="58" /> provide a vision on the needs for faster recovery from the pandemic and increasing the resilience of the construction industrial ecosystem. Among the priority actions is the enhancement of safety, sustainability and climate resilience in the built environment in the context of the upgrade of the European standards for the design of structures (i.e the EN Eurocodes: EN 1990 to EN 1999⁵⁹) and other relevant building standards.

The **new technical guidance on climate proofing of infrastructure in the period 2021-2027** <fnref n="60" /> sets out common principles, requirements and practices to deal with physical climate risks in major infrastructure projects - e.g., funded by the **European Regional Development Fund** <fnref n="61" />. To note that the term infrastructure in this guidance refers to buildings, network infrastructure, and a range of built systems and assets. The guidance rests on two pillars: mitigation and climate neutrality as well as adaptation and climate resilience. The EN Eurocodes are referenced as a tool for climate proofing of infrastructure.

Many climatic variables, and their extension into future climate change projections, are likely to have an impact on the safety of buildings and constructions. Indeed, buildings are threatened over their lifetime by a number of climate hazards, including the augment of temperature, frequency and magnitude of extreme weather events, river flooding or sea level rise, trends of acidity rainfall, etc., which might accelerate the degradation of construction materials and compromise their durability, particularly when they have not been designed to take account for future climatic conditions. Resilient structures must anticipate, prepare for, and adapt to changing climatic conditions, react quickly, and recover quickly. They should significantly reduce climate risks for themselves, occupants, environment, and assets by minimizing adverse effects on their components.

## 1.2 JRC activities in support of adaptation of structural design to climate change

Numerous policies and initiatives referenced previously in Sub-section 1.1 will impact the building sector development and the construction market evolution and capacity for adaptation to climate challenges in the future. Climate change significantly impacts buildings in Europe, causing heat waves, storms, heavy precipitation, and flooding events. To address these increasing numbers of hazards, effective adaptation measures must be resilient to multiple hazards. Technical guidance on climate-adaptation measures is needed for both new and existing buildings across different climatic zones. Solutions should reduce climate risks with involved stakeholders being oriented to improve building performance.

In 2022, the Commission and the European Environment Agency initiated the preparation of the **first European Climate Risk Assessment** (EUCRA)<fnref n="62" />. This independent scientific report will assess current and future climate change impacts and risks relating to the environment, economy and wider society in Europe. The assessment will also address cross-border, cascading and compound risks. It will also address key actions to mitigate the climate risk for infrastructure, focussing on transport and energy networks, buildings (as regards the design and standards), and water use and management infrastructure. Publication of the report is foreseen for 2024.

The Commission action plan for implementing the New EU Strategy on Adaptation to Climate Change (COM (2021) 82)⁵ includes activities in support to integration of climate resilience considerations into the criteria applicable to construction and renovation of buildings and critical infrastructure. Along this line, the Commission integrated climate resilience in its December 2021 proposal for the revision of the Energy Performance of Buildings Directive (EPBD), which will make it mandatory for Member States to address climate change adaptation for both new and existing buildings. Moreover, the Commission put forward provisions to inform about the performance of construction products also under future climate in its March 2022 proposal for the revision of the Construction Products Regulation. Among the other activities to be performed by the Commission, the **Report on the Implementation of the EU Strategy on Adaptation to Climate Change** (SWD(2023) 339)⁶ mentions the Joint Research Centre (JRC) activities regarding the study on climate change induced corrosion, estimating the total repair costs of reinforced concrete buildings, as well as the JRC pilot studies on

<footnote n="58">⁵⁸ Commission Staff Working Paper (2021), Scenarios for a transition pathway for a greener, more digital and resilient construction ecosystem, SWD(2021) 419 final, https://ec.europa.eu/docsroom/documents/47996</footnote>

<footnote n="59">⁵⁹ https://eurocodes.jrc.ec.europa.eu/</footnote>

<footnote n="60">⁶⁰ COMMISSION NOTICE, 2021. Technical guidance on the climate proofing of infrastructure in the period 2021-2027 (2021/C 373/01)</footnote>

<footnote n="61">⁶¹ Regulation (EU) 2021/1058 of the European Parliament and of the Council of 24 June 2021 on the European Regional Development Fund and on the Cohesion Fund, PE/48/2021/INIT</footnote>

<footnote n="62">⁶² In May 2022, the Directorate-General for Climate Action of the European Commission (DG CLIMA) and the European Environment Agency (EEA) initiated the preparation of the first European Climate Risk Assessment (EUCRA). The EUCRA assesses current and future climate change impacts and risks relating to the environment, economy and wider society in Europe.</footnote>
the future climatic loading on structures which support Member States in updating their provisions for design and renovation of built environment.

The Safety and Security of Buildings Unit of the JRC is performing activities on identifying needs and approaches for adaptation of built environment to climate change, in the framework of Administrative Arrangements with the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROW), and in close collaboration with DG CLIMA. The JRC is leading an expert network on adaptation of built environment to climate change, participated by: DG CLIMA, DG GROW, European Environmental Agency, Copernicus Climate Change Service, CEN/CENELEC, CEN/TC250 ‘Structural Eurocodes’, experts from the Euro-Mediterranean Centre on Climate Change (CCMC) in Italy, Delft University of Technology in the Netherlands, Czech Technical University in Prague, Coimbra University in Portugal, University of Nottingham in the United Kingdom and University of Nantes in France.

The main JRC activities in the area of climate change adaptation of built environment are focused on:

* Incorporation of climate change adaptation in the European standards for design and renovation of buildings and infrastructure (Eurocodes) and their national applications (climatic loading maps), (Croce et al, 2018⁶³; Athanasopoulou et al, 2020⁶⁴; Rianna et al, 2023⁶⁵)

* Expected climatic actions on structures (snow, thermal, wind,...) in the period 2020-2100 (Croce et al., 2018; Athanasopoulou et al., 2020);

* Climatic data for structural design (development of new part of Climate ADAPT portal on built environment);

* Climate change induced corrosion of built environment (Sousa et al. 2020)<fnref n="66" />.

In a previous JRC report devoted to the climate change induced corrosion Sousa et al., 2020 analysed the existing studies of corrosion of structures due to climate change, concluding that changes in temperature, concentration of pollutants, rainfall patterns, etc. could have a significant impact on the service life of structures and cannot be ignored. The impact of climate change on the corrosion of reinforced concrete and steel structures in Europe is a significant concern. The rising levels of CO₂ and global warming are accelerating the corrosion of the reinforcement in buildings and infrastructure, which compromises their lifespan and serviceability.

Sousa et al. (2020) emphasize the need for quantitative assessments that consider variations in environmental factors, incorporate adaptation and mitigation measures, and utilize a geo-referenced database of European building stock to effectively address this issue. The authors observed that most of the studies analysed in that report were carried out outside Europe or targeted European specific locations and materials, not allowing to extract global conclusions. Furthermore, it is important to address the need for comprehensive data collection and analysis in regions that are particularly susceptible to the impact of corrosion. This will provide a more accurate understanding of the specific challenges and risks faced in these areas, enabling the development of targeted adaptation strategies and effective measures to better mitigate and adapt to the effects of climate change.

As a result, the current study presents the first evaluation of the implications of the climate change induced carbonation on the entire concrete building stock in the EU-27 Member States. The work simulates the impact of potential climate scenarios on selected corrosion metrics and makes comparison to a reference situation with no further change of the climate. The overall assessments of the repair costs are further performed for each EU Member State. Finally, the most affected regions in Europe due to climate change-induced corrosion are identified and the corrosion costs are compared with other economic and societal risks evaluated in previous studies, for instance in PESETA IV²⁸. Finally, the study addresses two adaptation strategies: the first referring to measures integrated during the design phase for new structures, and the second involving measures implemented during the service phase to enhance the resilience of existing structures.

<footnote n="63">⁶³ Croce, P., Formichi, P., Landi, F., Mercogliano, P., Bucchignani, E., Dosio, A., Dimova, S., 'The snow load in Europe and the climate change', *Climate Risk Management*, Volume 20, 2018, pp. 138-154, ISSN 2212-0963, https://doi.org/10.1016/j.crm.2018.03.001.</footnote>

<footnote n="64">⁶⁴ Athanasopoulou, A., Raposo De M. Do N. E S. De Sotto Mayor, M., Dimova, S., Guido, R., Mercogliano, P., Villani, V., Croce, P., Landi, F., Formichi, P. and Markova, J., 'Thermal design of structures and the changing climate', EUR 30302 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20777-1, doi:10.2760/40470, JRC121351.</footnote>

<footnote n="65">⁶⁵ Rianna, G., Reder, A., Sousa, M.L., Dimova, S., 'Harmonised procedure to update thermal loads in the Eurocodes. Case study for Italy', *Climate Services*, Volume 30, 2023, 100391, ISSN 2405-8807, https://doi.org/10.1016/j.cliser.2023.100391</footnote>

<footnote n="66">⁶⁶ Sousa, M.L., M., Dimova, S., Athanasopoulou, A., Rianna, G., Mercogliano, P., Villani, V., Nogal, M., Dos Santos Gervasio, H., Neves, L., Bastidas-Arteaga, E. and Tsionis, G., 'Expected implications of climate change on the corrosion of structures', EUR 30303 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20782-5, doi:10.2760/05229, JRC121312.</footnote>
the future climatic loading on structures which support Member States in updating their provisions for design and renovation of built environment.

The Safety and Security of Buildings Unit of the JRC is performing activities on identifying needs and approaches for adaptation of built environment to climate change, in the framework of Administrative Arrangements with the Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROW), and in close collaboration with DG CLIMA. The JRC is leading an expert network on adaptation of built environment to climate change, participated by: DG CLIMA, DG GROW, European Environmental Agency, Copernicus Climate Change Service, CEN/CENELEC, CEN/TC250 ‘Structural Eurocodes’, experts from the Euro-Mediterranean Centre on Climate Change (CCMC) in Italy, Delft University of Technology in the Netherlands, Czech Technical University in Prague, Coimbra University in Portugal, University of Nottingham in the United Kingdom and University of Nantes in France.

The main JRC activities in the area of climate change adaptation of built environment are focused on:

* Incorporation of climate change adaptation in the European standards for design and renovation of buildings and infrastructure (Eurocodes) and their national applications (climatic loading maps), (Croce et al, 2018⁶³; Athanasopoulou et al, 2020⁶⁴; Rianna et al, 2023⁶⁵)

* Expected climatic actions on structures (snow, thermal, wind,...) in the period 2020-2100 (Croce et al., 2018; Athanasopoulou et al., 2020);

* Climatic data for structural design (development of new part of Climate ADAPT portal on built environment);

* Climate change induced corrosion of built environment (Sousa et al. 2020)<fnref n="66" />.

In a previous JRC report devoted to the climate change induced corrosion Sousa et al., 2020 analysed the existing studies of corrosion of structures due to climate change, concluding that changes in temperature, concentration of pollutants, rainfall patterns, etc. could have a significant impact on the service life of structures and cannot be ignored. The impact of climate change on the corrosion of reinforced concrete and steel structures in Europe is a significant concern. The rising levels of CO₂ and global warming are accelerating the corrosion of the reinforcement in buildings and infrastructure, which compromises their lifespan and serviceability.

Sousa et al. (2020) emphasize the need for quantitative assessments that consider variations in environmental factors, incorporate adaptation and mitigation measures, and utilize a geo-referenced database of European building stock to effectively address this issue. The authors observed that most of the studies analysed in that report were carried out outside Europe or targeted European specific locations and materials, not allowing to extract global conclusions. Furthermore, it is important to address the need for comprehensive data collection and analysis in regions that are particularly susceptible to the impact of corrosion. This will provide a more accurate understanding of the specific challenges and risks faced in these areas, enabling the development of targeted adaptation strategies and effective measures to better mitigate and adapt to the effects of climate change.

As a result, the current study presents the first evaluation of the implications of the climate change induced carbonation on the entire concrete building stock in the EU-27 Member States. The work simulates the impact of potential climate scenarios on selected corrosion metrics and makes comparison to a reference situation with no further change of the climate. The overall assessments of the repair costs are further performed for each EU Member State. Finally, the most affected regions in Europe due to climate change-induced corrosion are identified and the corrosion costs are compared with other economic and societal risks evaluated in previous studies, for instance in PESETA IV²⁸. Finally, the study addresses two adaptation strategies: the first referring to measures integrated during the design phase for new structures, and the second involving measures implemented during the service phase to enhance the resilience of existing structures.

<footnote n="63">⁶³ Croce, P., Formichi, P., Landi, F., Mercogliano, P., Bucchignani, E., Dosio, A., Dimova, S., 'The snow load in Europe and the climate change', *Climate Risk Management*, Volume 20, 2018, pp. 138-154, ISSN 2212-0963, https://doi.org/10.1016/j.crm.2018.03.001.</footnote>

<footnote n="64">⁶⁴ Athanasopoulou, A., Raposo De M. Do N. E S. De Sotto Mayor, M., Dimova, S., Guido, R., Mercogliano, P., Villani, V., Croce, P., Landi, F., Formichi, P. and Markova, J., 'Thermal design of structures and the changing climate', EUR 30302 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20777-1, doi:10.2760/40470, JRC121351.</footnote>

<footnote n="65">⁶⁵ Rianna, G., Reder, A., Sousa, M.L., Dimova, S., 'Harmonised procedure to update thermal loads in the Eurocodes. Case study for Italy', *Climate Services*, Volume 30, 2023, 100391, ISSN 2405-8807, https://doi.org/10.1016/j.cliser.2023.100391</footnote>

<footnote n="66">⁶⁶ Sousa, M.L., M., Dimova, S., Athanasopoulou, A., Rianna, G., Mercogliano, P., Villani, V., Nogal, M., Dos Santos Gervasio, H., Neves, L., Bastidas-Arteaga, E. and Tsionis, G., 'Expected implications of climate change on the corrosion of structures', EUR 30303 EN, Publications Office of the European Union, Luxembourg, 2020, ISBN 978-92-76-20782-5, doi:10.2760/05229, JRC121312.</footnote>
1.3 Organisation of the report

**Chapter 1** of the report presents briefly the EU policy context and background in relation to climate change adaptation for the built environment and summarises the JRC activities in support of the adaptation of structural design to climate change.

**Chapter 2** introduces the problem of the corrosion of concrete structures due to climate change, describing the mechanism of carbonation-induced corrosion influenced by the climate change and discusses models for the assessment of the carbonation depth.

**Chapter 3** provides insight on modelling the repair costs of carbonation-induced corrosion and presents the assumptions accepted in this study.

**Chapter 4** presents the climatic data used in this study in the context of the pan-European temperature values for recent decades and their future projections.

A characterisation of the European building stock, in particular for the reinforced concrete buildings and their durability parameters is presented in **Chapter 5**.

**Chapter 6** starts with an overview of the data and methods used to assess the climate change impact on the European reinforced concrete building stock, and presents the results obtained in terms of carbonation damage and repair costs needed.

**Chapter 7** discusses the economic impact of climate change-induced corrosion of the European reinforced concrete building stock and compares the results obtained with other assessments of implications of the climate change.

A proposal for adaptation strategies is elaborated in **Chapter 8**.

The main conclusions and recommendations stemming from the study are summarised in **Chapter 9**.
## 1.3 Organisation of the report

**Chapter 1** of the report presents briefly the EU policy context and background in relation to climate change adaptation for the built environment and summarises the JRC activities in support of the adaptation of structural design to climate change.

**Chapter 2** introduces the problem of the corrosion of concrete structures due to climate change, describing the mechanism of carbonation-induced corrosion influenced by the climate change and discusses models for the assessment of the carbonation depth.

**Chapter 3** provides insight on modelling the repair costs of carbonation-induced corrosion and presents the assumptions accepted in this study.

**Chapter 4** presents the climatic data used in this study in the context of the pan-European temperature values for recent decades and their future projections.

A characterisation of the European building stock, in particular for the reinforced concrete buildings and their durability parameters is presented in **Chapter 5**.

**Chapter 6** starts with an overview of the data and methods used to assess the climate change impact on the European reinforced concrete building stock, and presents the results obtained in terms of carbonation damage and repair costs needed.

**Chapter 7** discusses the economic impact of climate change-induced corrosion of the European reinforced concrete building stock and compares the results obtained with other assessments of implications of the climate change.

A proposal for adaptation strategies is elaborated in **Chapter 8**.

The main conclusions and recommendations stemming from the study are summarised in **Chapter 9**.
# 2 Corrosion of concrete structures due to climate change

## 2.1 Scope of the study

Concrete is clearly one of the most predominant-used material in both residential and non-residential structures across Europe (Peled and Fishman, 2021). A reinforced concrete (RC) structure is expected to satisfy criteria for serviceability, structural integrity, and stability over its designed operational lifespan, without significant loss of utility or excessive unforeseen maintenance (for general requirements see also EN 1990). Comprehending the degradation mechanisms that impact these structures is essential for accurately estimating their service life and formulating cost-effective maintenance strategies. The main mechanisms responsible for concrete degradation include corrosion caused by carbonation and the presence of chloride ions, freeze-thaw cycles, sulphate attack and erosion due to high-velocity water flow, ice, or wind-blown sand.

Carbonation refers to the reaction between carbon dioxide in the air and calcium hydroxide in the concrete resulting in loss of alkalinity, thereby affecting the passivity of the reinforcing steel and making it susceptible to corrosion. This process is known as carbonation-induced corrosion. The initiation and progression of the carbonation-induced corrosion process are significantly influenced by environmental conditions. Temperature, atmospheric humidity and levels of carbon dioxide ($CO_2$) concentration serve as the main environmental factors influencing this degradation mechanism. The escalation in these environmental drivers is directly attributable to climate change and prevalent $CO_2$ emissions. The literature indicates an increase in corrosion depths due to carbonation ranging from 40-45% by the year 2100, as compared to the climate conditions observed in 2000, under the Representative Concentration Pathway 8.5 (RCP8.5) or equivalent A1FI scenarios (Talukdar et al. 2012b and 2013; Saha and Eckelman 2014; Peng and Stewart 2014; Mizzi et al. 2018). Consequently, the financial implications of augmented maintenance and repair costs are substantial, estimated to be in the range of hundreds of billions of dollars annually (Bastidas-Arteaga and Stewart, 2015). For a detailed discussion of the implications of climate change on the corrosion of reinforced concrete, the reader is referred to Sousa et al. (2020).

On the other hand, chloride-induced corrosion is caused when chloride ions penetrate the concrete and initiate corrosion of the reinforcing steel. The permeation mechanism for these ions is notably influenced by temperature and humidity conditions. Therefore, the chloride-induced corrosion process is similarly susceptible to alterations in climate conditions. For an updated review of the mechanisms of chloride-induced corrosion the reader is referred to Rincon et al. (2023). The existing literature reports increments of chloride concentration at the rebar-level depths ranging from 6-15% by 2100 when compared with the climate conditions in 2000 under the RCP8.5 or equivalent A1FI scenarios (Xie et al. 2018, Saha and Eckelman 2014). Notably, this corrosion type is predominantly observed in marine environments and in regions susceptible to snowfall, where the application of de-icing salts is routine. **Given the relatively limited geographical prevalence and comparatively lower impact of the chloride-induced corrosion, this report focusses on the carbonation-induced corrosion. For the remainder of this document, carbonation-induced corrosion will be referred to simply as corrosion.**

The studies on the impact of climate change on corrosion has mainly focused on civil infrastructures and there are only a few studies analysing its impact on the building stock. Saha and Eckelman (2014) found that, for around 60% of the existing RC buildings in the Boston metropolitan area, the penetration depths of carbonation will reach the rebar level by 2050 (A1FI scenario), while their service life will be reduced by 26 years by the end of the century. In Europe, Finnish buildings have been studied by Köliö et al (2014) and Pakkala et al (2019). They found that the corrosion rate during winter in the coastal region is expected to increase 200% for the facades facing to the South under RCP8.5 scenario.

The corrosion rate is influenced by several factors including geographical conditions, structural design in accordance with standards, material composition, age, and the effectiveness of inspection and maintenance strategies (Nogal et al, 2021). Geographical conditions, in particular, correlate with the effects of climate change, manifested in diverse temperature and relative humidity fluctuations across different regions. However, there is limited research on the impact of climate change on concrete deterioration in buildings across Europe and further investigation is required.

The following sub-section of this chapter provides an overview of the mechanism underlying carbonation-induced corrosion and examines the influence of different parameters in climate-induced variations. Then, the chapter discusses various corrosion models and evaluates their suitability for assessing the corrosion risk to the reinforced concrete (RC) building stock across Europe, considering future climate change scenarios.
# 2 Corrosion of concrete structures due to climate change

## 2.1 Scope of the study

Concrete is clearly one of the most predominant-used material in both residential and non-residential structures across Europe (Peled and Fishman, 2021). A reinforced concrete (RC) structure is expected to satisfy criteria for serviceability, structural integrity, and stability over its designed operational lifespan, without significant loss of utility or excessive unforeseen maintenance (for general requirements see also EN 1990). Comprehending the degradation mechanisms that impact these structures is essential for accurately estimating their service life and formulating cost-effective maintenance strategies. The main mechanisms responsible for concrete degradation include corrosion caused by carbonation and the presence of chloride ions, freeze-thaw cycles, sulphate attack and erosion due to high-velocity water flow, ice, or wind-blown sand.

Carbonation refers to the reaction between carbon dioxide in the air and calcium hydroxide in the concrete resulting in loss of alkalinity, thereby affecting the passivity of the reinforcing steel and making it susceptible to corrosion. This process is known as carbonation-induced corrosion. The initiation and progression of the carbonation-induced corrosion process are significantly influenced by environmental conditions. Temperature, atmospheric humidity and levels of carbon dioxide ($CO_2$) concentration serve as the main environmental factors influencing this degradation mechanism. The escalation in these environmental drivers is directly attributable to climate change and prevalent $CO_2$ emissions. The literature indicates an increase in corrosion depths due to carbonation ranging from 40-45% by the year 2100, as compared to the climate conditions observed in 2000, under the Representative Concentration Pathway 8.5 (RCP8.5) or equivalent A1FI scenarios (Talukdar et al. 2012b and 2013; Saha and Eckelman 2014; Peng and Stewart 2014; Mizzi et al. 2018). Consequently, the financial implications of augmented maintenance and repair costs are substantial, estimated to be in the range of hundreds of billions of dollars annually (Bastidas-Arteaga and Stewart, 2015). For a detailed discussion of the implications of climate change on the corrosion of reinforced concrete, the reader is referred to Sousa et al. (2020).

On the other hand, chloride-induced corrosion is caused when chloride ions penetrate the concrete and initiate corrosion of the reinforcing steel. The permeation mechanism for these ions is notably influenced by temperature and humidity conditions. Therefore, the chloride-induced corrosion process is similarly susceptible to alterations in climate conditions. For an updated review of the mechanisms of chloride-induced corrosion the reader is referred to Rincon et al. (2023). The existing literature reports increments of chloride concentration at the rebar-level depths ranging from 6-15% by 2100 when compared with the climate conditions in 2000 under the RCP8.5 or equivalent A1FI scenarios (Xie et al. 2018, Saha and Eckelman 2014). Notably, this corrosion type is predominantly observed in marine environments and in regions susceptible to snowfall, where the application of de-icing salts is routine. **Given the relatively limited geographical prevalence and comparatively lower impact of the chloride-induced corrosion, this report focusses on the carbonation-induced corrosion. For the remainder of this document, carbonation-induced corrosion will be referred to simply as corrosion.**

The studies on the impact of climate change on corrosion has mainly focused on civil infrastructures and there are only a few studies analysing its impact on the building stock. Saha and Eckelman (2014) found that, for around 60% of the existing RC buildings in the Boston metropolitan area, the penetration depths of carbonation will reach the rebar level by 2050 (A1FI scenario), while their service life will be reduced by 26 years by the end of the century. In Europe, Finnish buildings have been studied by Köliö et al (2014) and Pakkala et al (2019). They found that the corrosion rate during winter in the coastal region is expected to increase 200% for the facades facing to the South under RCP8.5 scenario.

The corrosion rate is influenced by several factors including geographical conditions, structural design in accordance with standards, material composition, age, and the effectiveness of inspection and maintenance strategies (Nogal et al, 2021). Geographical conditions, in particular, correlate with the effects of climate change, manifested in diverse temperature and relative humidity fluctuations across different regions. However, there is limited research on the impact of climate change on concrete deterioration in buildings across Europe and further investigation is required.

The following sub-section of this chapter provides an overview of the mechanism underlying carbonation-induced corrosion and examines the influence of different parameters in climate-induced variations. Then, the chapter discusses various corrosion models and evaluates their suitability for assessing the corrosion risk to the reinforced concrete (RC) building stock across Europe, considering future climate change scenarios.
Subsequently, the model adopted for the assessment of the carbonation depth is described in the last section of the chapter.

## 2.2 Mechanism of carbonation-induced corrosion influenced by climate change

Environmental parameters such as humidity, temperature, and carbon dioxide concentration, coupled with concrete-specific factors such as alkalinity and permeability, influence both the carbonation rate and its depth (Yoon and Chang, 2020; Parrot, 1999; Stefanoni, Angst and Elsener 2018). The carbonation process initiates at the concrete's outer layer, generating a front of decreased alkalinity that progresses with ongoing CO₂ diffusion and reaction. When the carbonation depth extends to the reinforcing bar (rebar) level, the phase transitions from corrosion initiation to corrosion propagation. During this latter stage, aggressive agents de-passivate the reinforcement, leading to a compromised state that fails to satisfy the structural safety, stability, functionality, and aesthetic requirements. While the carbonation initiation stage dominates the structural service life spanning several decades, the propagation typically lasts only a few years. The measure used to study the severity of the carbonation is the carbonation depth, which is quantified as the average distance from the concrete surface where alkalinity has decreased.

Climate change is inducing shifts in environmental temperatures and Relative Humidity (RH) levels. The extent to which climate change accelerates corrosion depends on the magnitude, direction, and range of these temperature and RH fluctuations. Several mathematical models have been proposed that capture the complex interplay between temperature and RH in the corrosion process (e.g., Stewart et al, 2011). The estimation of the impact on the corrosion rate according to these models can be determined through sensitivity analysis. This allows to make simplifications in the numerical analysis without a loss of credibility in the results.

Accordingly, various studies analyse the impact of climate change on the corrosion rate depending on the geographical location. Some studies consider the spatial variability with respect to the temperature, such as Talukdar and Banthia (2013) in locations in India, UK, USA, Canada and Australia, Mizzi et al (2018) in Malta and Bastidas-Arteaga et al (2022) in Portugal. Other research projects study the spatial variability caused by both, temperature and RH. For instance, Peng and Stewart (2014) study several locations across China and De Larrard et al. (2014) examined six different locations in France.

Many authors claim that relative humidity might influence significantly the carbonation depth (Parrott, 1994; ShieBl, 1997; fib, 2006; Yoon et al., 2007). A minimum relative humidity (RH) threshold of 30-50% is needed for carbonation reactions (Russell et al. 2001; Al-Khaiat and Fattuhi 2002). The maximum carbonation rate occurs at RH of 60-90% (Garces 2021; Ho and Lewis, 1987).

Elsalamawy et al. (2019) compared different models for the calculation of carbonation depth taking into account RH and compared the results with accelerated carbonation tests. Based on the results of such tests, for different cement types, the authors observed that the carbonation depth increased with the increase of RH to reach a peak value at 65% RH, independently of the cement type, as illustrated Figure 1.

<figure><img src="image_5.png" /><figcaption>**Figure 1.** Influence of RH in the carbonation depth (Elsalamawy et al., 2019).</figcaption></figure>
Subsequently, the model adopted for the assessment of the carbonation depth is described in the last section of the chapter.

## 2.2 Mechanism of carbonation-induced corrosion influenced by climate change

Environmental parameters such as humidity, temperature, and carbon dioxide concentration, coupled with concrete-specific factors such as alkalinity and permeability, influence both the carbonation rate and its depth (Yoon and Chang, 2020; Parrot, 1999; Stefanoni, Angst and Elsener 2018). The carbonation process initiates at the concrete's outer layer, generating a front of decreased alkalinity that progresses with ongoing CO₂ diffusion and reaction. When the carbonation depth extends to the reinforcing bar (rebar) level, the phase transitions from corrosion initiation to corrosion propagation. During this latter stage, aggressive agents de-passivate the reinforcement, leading to a compromised state that fails to satisfy the structural safety, stability, functionality, and aesthetic requirements. While the carbonation initiation stage dominates the structural service life spanning several decades, the propagation typically lasts only a few years. The measure used to study the severity of the carbonation is the carbonation depth, which is quantified as the average distance from the concrete surface where alkalinity has decreased.

Climate change is inducing shifts in environmental temperatures and Relative Humidity (RH) levels. The extent to which climate change accelerates corrosion depends on the magnitude, direction, and range of these temperature and RH fluctuations. Several mathematical models have been proposed that capture the complex interplay between temperature and RH in the corrosion process (e.g., Stewart et al, 2011). The estimation of the impact on the corrosion rate according to these models can be determined through sensitivity analysis. This allows to make simplifications in the numerical analysis without a loss of credibility in the results.

Accordingly, various studies analyse the impact of climate change on the corrosion rate depending on the geographical location. Some studies consider the spatial variability with respect to the temperature, such as Talukdar and Banthia (2013) in locations in India, UK, USA, Canada and Australia, Mizzi et al (2018) in Malta and Bastidas-Arteaga et al (2022) in Portugal. Other research projects study the spatial variability caused by both, temperature and RH. For instance, Peng and Stewart (2014) study several locations across China and De Larrard et al. (2014) examined six different locations in France.

Many authors claim that relative humidity might influence significantly the carbonation depth (Parrott, 1994; ShieBl, 1997; fib, 2006; Yoon et al., 2007). A minimum relative humidity (RH) threshold of 30-50% is needed for carbonation reactions (Russell et al. 2001; Al-Khaiat and Fattuhi 2002). The maximum carbonation rate occurs at RH of 60-90% (Garces 2021; Ho and Lewis, 1987).

Elsalamawy et al. (2019) compared different models for the calculation of carbonation depth taking into account RH and compared the results with accelerated carbonation tests. Based on the results of such tests, for different cement types, the authors observed that the carbonation depth increased with the increase of RH to reach a peak value at 65% RH, independently of the cement type, as illustrated Figure 1.

<figure><img src="image_6.png" /><figcaption>**Figure 1.** Influence of RH in the carbonation depth (Elsalamawy et al., 2019).</figcaption></figure>
Temperature also plays a role in corrosion speed, with higher temperatures promoting ion movement and lower temperatures causing condensation and higher humidity levels. The corrosion rate is, therefore, highly sensitive to changes in the environmental conditions.

Despite the crucial role of the RH in the corrosion process, the increments of carbonation depths observed in the above works, with and without the consideration of the RH, are of the same range, around 40-45% as mentioned before. This may be due to the relatively small variation in the RH according to the climatic projections in comparison with the large variation in temperature and CO₂ emissions. For instance, in Europe, increments of 4°C to 6°C are expected by 2100 in most European areas (RCP8.5) reaching 8°C to 10°C in the Northern regions. In contrasts, only minor variations are anticipated in terms of RH: 4% to 10% in some northernmost regions, while some Mediterranean countries could even experience a reduction of RH (Sousa et al., 2020). Note that, in some cases, a decrease in RH may reduce the corrosion rate. Nonetheless, the results are limited to the European context and specific mathematical models, and they should be approached with caution in locations with distinct climatic conditions.

The same trend was observed in a sensitivity analysis carried out by Bastidas-Arteaga et al. (2022). In this case, the expected range of variation of temperature and RH in three different locations in Portugal was analysed, observing the impact on the carbonation depth of reinforced concrete structures. The selection of the locations was made to obtain a wide variability in terms of temperature and RH. The results shown the importance of considering specific exposure conditions at a correct scale in the lifetime assessment, as for example, in some cases a decrease in RH variation was not enough to counterbalance the effect of the increment in temperature and CO₂.

Considering that for an accurate estimation a more detailed scale is required, this report does not analyse the effect of RH variation on the corrosion rate across Europe. Instead, it focuses on the projections of CO₂ levels and the temperature shifts due to climate change to assess potential changes in the corrosion depth, as detailed in the subsequent section.

## 2.3 Selection of model for assessment of carbonation depth

Concrete contains calcium hydroxide in pores due to the hydration reaction of C₃S tricalcium silicate (3CaO·SiO₂) and C₂S dicalcium silicate (2CaO·SiO₂) in cement, maintaining an alkaline environment with a pH of 12.5 to 13.0. Carbonation occurs when CO₂ gas diffuses into concrete, consuming calcium hydroxide and causing a decrease in pore solution pH. This can lead to reinforcement corrosion, reducing concrete's long-term durability. Calculating carbonation rate is crucial for predicting service life and CO₂ diffusivity (Yoon et al. 2020).

As already referred, the assessment of the impact of climate change is made in terms of the carbonation depth in reinforced concrete buildings, as this metric has been used extensively by many authors to predict the service life of structures. Different models are available in the literature for the quantification of the carbonation depth. Most widespread models are based on a static environment, but the aim of this study is to model reinforced concrete deterioration affected by spatially and temporally climate-dependent variables.

In the carbonation process, the time to corrosion initiation depends on many factors, such as concrete type and quality, concrete cover, relative humidity (RH), carbon dioxide (CO₂) concentration, among others. Among mathematical models that have been proposed in the literature over the years for the assessment of the carbonation depth in reinforced concrete structures, the most common approach is based on Fick's first law of diffusion. In this case, the carbonation depth, x_c(t), increases as a function of the square root of time, as given by expression (1) (Yoon et al., 2007):

$$x_c(t)=K_c \sqrt{t} \qquad (1)$$

where x_c(t) is the carbonation depth (in mm) at the time (t) of exposure (in years) to carbon dioxide, CO₂ and K_c is the carbonation coefficient (in mm/year⁰.⁵) that reflects the influence of the environmental conditions and concrete quality. Over time, the rate at which carbonation occurs in waterproof concrete and humid environments decreases significantly, eventually becoming insignificant (Saura Gómez et al. 2023).

The carbonation model recommended by Yoon et al. (2007) takes into account a diffusion coefficient (D<sub>CO₂</sub>), since carbonation depth is very much dependent on this coefficient as given by expression (2):
Temperature also plays a role in corrosion speed, with higher temperatures promoting ion movement and lower temperatures causing condensation and higher humidity levels. The corrosion rate is, therefore, highly sensitive to changes in the environmental conditions.

Despite the crucial role of the RH in the corrosion process, the increments of carbonation depths observed in the above works, with and without the consideration of the RH, are of the same range, around 40-45% as mentioned before. This may be due to the relatively small variation in the RH according to the climatic projections in comparison with the large variation in temperature and CO₂ emissions. For instance, in Europe, increments of 4°C to 6°C are expected by 2100 in most European areas (RCP8.5) reaching 8°C to 10°C in the Northern regions. In contrasts, only minor variations are anticipated in terms of RH: 4% to 10% in some northernmost regions, while some Mediterranean countries could even experience a reduction of RH (Sousa et al., 2020). Note that, in some cases, a decrease in RH may reduce the corrosion rate. Nonetheless, the results are limited to the European context and specific mathematical models, and they should be approached with caution in locations with distinct climatic conditions.

The same trend was observed in a sensitivity analysis carried out by Bastidas-Arteaga et al. (2022). In this case, the expected range of variation of temperature and RH in three different locations in Portugal was analysed, observing the impact on the carbonation depth of reinforced concrete structures. The selection of the locations was made to obtain a wide variability in terms of temperature and RH. The results shown the importance of considering specific exposure conditions at a correct scale in the lifetime assessment, as for example, in some cases a decrease in RH variation was not enough to counterbalance the effect of the increment in temperature and CO₂.

Considering that for an accurate estimation a more detailed scale is required, this report does not analyse the effect of RH variation on the corrosion rate across Europe. Instead, it focuses on the projections of CO₂ levels and the temperature shifts due to climate change to assess potential changes in the corrosion depth, as detailed in the subsequent section.

## 2.3 Selection of model for assessment of carbonation depth

Concrete contains calcium hydroxide in pores due to the hydration reaction of C₃S tricalcium silicate (3CaO·SiO₂) and C₂S dicalcium silicate (2CaO·SiO₂) in cement, maintaining an alkaline environment with a pH of 12.5 to 13.0. Carbonation occurs when CO₂ gas diffuses into concrete, consuming calcium hydroxide and causing a decrease in pore solution pH. This can lead to reinforcement corrosion, reducing concrete's long-term durability. Calculating carbonation rate is crucial for predicting service life and CO₂ diffusivity (Yoon et al. 2020).

As already referred, the assessment of the impact of climate change is made in terms of the carbonation depth in reinforced concrete buildings, as this metric has been used extensively by many authors to predict the service life of structures. Different models are available in the literature for the quantification of the carbonation depth. Most widespread models are based on a static environment, but the aim of this study is to model reinforced concrete deterioration affected by spatially and temporally climate-dependent variables.

In the carbonation process, the time to corrosion initiation depends on many factors, such as concrete type and quality, concrete cover, relative humidity (RH), carbon dioxide (CO₂) concentration, among others. Among mathematical models that have been proposed in the literature over the years for the assessment of the carbonation depth in reinforced concrete structures, the most common approach is based on Fick's first law of diffusion. In this case, the carbonation depth, x_c(t), increases as a function of the square root of time, as given by expression (1) (Yoon et al., 2007):

$$x_c(t)=K_c \sqrt{t} \quad (1)$$

where x_c(t) is the carbonation depth (in mm) at the time (t) of exposure (in years) to carbon dioxide, CO₂ and K_c is the carbonation coefficient (in mm/year⁰.⁵) that reflects the influence of the environmental conditions and concrete quality. Over time, the rate at which carbonation occurs in waterproof concrete and humid environments decreases significantly, eventually becoming insignificant (Saura Gómez et al. 2023).

The carbonation model recommended by Yoon et al. (2007) takes into account a diffusion coefficient (D<sub>CO₂</sub>), since carbonation depth is very much dependent on this coefficient as given by expression (2):
$$x_c(t) = \sqrt{\frac{2D_{CO_2}(t)}{a}} C_{CO_2} \cdot (t-t_0) \quad (2)$$

where, $C_{CO_2}$ is the mass concentration of CO₂ in the environment (kg/m³); $k_{urban}$ is a factor that takes into account the increased concentration of CO₂ in urban areas; a is a factor that takes into account cement characteristics, given by expression (4); $t_0$ is the initial year; $n_m$ is the age factor for microclimatic conditions; and $D_{CO_2}$ is a diffusion coefficient dependent on time and temperature, given by:

$$D_{CO_2}(t) = D_1(t-t_0)^{-n_d} \quad (3)$$

where $D_1$ is the initial CO₂ diffusion coefficient, and $n_d$ is the aging factor.

On the other hand, the factor 'a' in equation (2), taking into account cement characteristics is given by:

$$a = 0.75 C_e \times C_{CaO} \times \alpha_H \frac{M_{CO_2}}{M_{CaO}} \quad (4)$$

where, $C_e$ is the cement content (kg/m³), $C_{CaO}$ is the calcium oxide content in the cement, $M_{CO_2}$ is the molar mass of CO₂, $M_{CaO}$ is the molar mass of CaO, and $\alpha_H$ is the degree of hydration, given by the following expression, as a function of the water to cement ratio (w/c):

$$\alpha_H \approx 1 - e^{-3.38w/c} \quad (5)$$

As already referred, the above model does not take into account the value of RH explicitly.

The model described by expression (2) considers that CO₂ concentrations are time-invariant. However, to consider climate change, the increased concentration of CO₂ in the atmosphere should be taken into account and thus, CO₂ concentration should be modelled as non-stationary process in the calculation of carbonation depth (Stewart et al., 2002). Therefore, the model adopted for the calculation of carbonation depth, which is described in the following paragraphs, takes into account the temporal variability of CO₂ concentrations as suggested by Stewart et al. (2002). This model is a function of temperature and CO₂ concentration over time, does not take into account relative humidity and is corrected by a coefficient ($k_{urban}$) that takes into account the increased levels of CO₂ in urban environments (Saha and Eckelmann, 2014). Additionally, the model does not take into account the concrete strength. Hence, according to this model, the carbonation depth $x_c$ over time t, in cm, is given by expression (6):

$$x_c(t) = \sqrt{\frac{2D_{CO_2}(t)}{a}} k_{urban} \int_{t_0}^{t} C_{CO_2}(t) dt \times \left(\frac{t_0}{t-t_0}\right)^{n_m} \quad (6)$$

where, $C_{CO_2}$ is the mass concentration of CO₂ in the environment (kg/m³); $t_0$ is the initial year; a is the factor that takes into consideration the cement characteristics, given by expression (4); $n_m$ is the age factor for microclimatic conditions; and $D_{CO_2}$ is a diffusion coefficient.

The diffusion coefficient is dependent on time and temperature, given by:

$$D_{CO_2}(t) = f_T(t) \cdot D_{0,CO_2}(t-t_0)^{-n_{d,CO_2}} \quad (7)$$

where, $D_{0,CO_2}$ is the initial CO₂ diffusion coefficient; $n_{d,CO_2}$ is the aging factor; and $f_T(t)$ is the time-dependent temperature factor, given by:

$$f_T(t) \approx \exp \left[ \frac{E}{R} \left( \frac{1}{293} - \frac{1}{273 + T_{\text{avg}}(t)} \right) \right] \quad (8)$$

where E is the activation energy of the diffusion process; R is the universal gas constant; and $T_{avg}(t)$ is the running average temperature (°C) over the period of time ($t - t_0$).

The model expressed by (6) is the adopted model in the following calculations.
$$x_c(t) = \sqrt{\frac{2D_{CO_2}(t)}{a}} C_{CO_2} \cdot (t-t_0) \qquad (2)$$

where, $C_{CO_2}$ is the mass concentration of CO₂ in the environment (kg/m³); $k_{urban}$ is a factor that takes into account the increased concentration of CO₂ in urban areas; a is a factor that takes into account cement characteristics, given by expression (4); $t_0$ is the initial year; $n_m$ is the age factor for microclimatic conditions; and $D_{CO_2}$ is a diffusion coefficient dependent on time and temperature, given by:

$$D_{CO_2}(t) = D_1(t-t_0)^{-n_d} \qquad (3)$$

where $D_1$ is the initial CO₂ diffusion coefficient, and $n_d$ is the aging factor.

On the other hand, the factor 'a' in equation (2), taking into account cement characteristics is given by:

$$a = 0.75 C_e \times C_{CaO} \times \alpha_H \frac{M_{CO_2}}{M_{CaO}} \qquad (4)$$

where, $C_e$ is the cement content (kg/m³), $C_{CaO}$ is the calcium oxide content in the cement, $M_{CO_2}$ is the molar mass of CO₂, $M_{CaO}$ is the molar mass of CaO, and $\alpha_H$ is the degree of hydration, given by the following expression, as a function of the water to cement ratio (w/c):

$$\alpha_H \approx 1 - e^{-3.38w/c} \qquad (5)$$

As already referred, the above model does not take into account the value of RH explicitly.

The model described by expression (2) considers that CO₂ concentrations are time-invariant. However, to consider climate change, the increased concentration of CO₂ in the atmosphere should be taken into account and thus, CO₂ concentration should be modelled as non-stationary process in the calculation of carbonation depth (Stewart et al., 2002). Therefore, the model adopted for the calculation of carbonation depth, which is described in the following paragraphs, takes into account the temporal variability of CO₂ concentrations as suggested by Stewart et al. (2002). This model is a function of temperature and CO₂ concentration over time, does not take into account relative humidity and is corrected by a coefficient ($k_{urban}$) that takes into account the increased levels of CO₂ in urban environments (Saha and Eckelmann, 2014). Additionally, the model does not take into account the concrete strength. Hence, according to this model, the carbonation depth $x_c$ over time t, in cm, is given by expression (6):

$$x_c(t) = \sqrt{\frac{2D_{CO_2}(t)}{a}} k_{urban} \int_{t_0}^{t} C_{CO_2}(t) dt \times \left(\frac{t_0}{t-t_0}\right)^{n_m} \qquad (6)$$

where, $C_{CO_2}$ is the mass concentration of CO₂ in the environment (kg/m³); $t_0$ is the initial year; a is the factor that takes into consideration the cement characteristics, given by expression (4); $n_m$ is the age factor for microclimatic conditions; and $D_{CO_2}$ is a diffusion coefficient.

The diffusion coefficient is dependent on time and temperature, given by:

$$D_{CO_2}(t) = f_T(t) \cdot D_{0,CO_2}(t-t_0)^{-n_{d,CO_2}} \qquad (7)$$

where, $D_{0,CO_2}$ is the initial CO₂ diffusion coefficient; $n_{d,CO_2}$ is the aging factor; and $f_T(t)$ is the time-dependent temperature factor, given by:

$$f_T(t) \approx \exp \left[ \frac{E}{R} \left( \frac{1}{293} - \frac{1}{273 + T_{\text{avg}}(t)} \right) \right] \qquad (8)$$

where E is the activation energy of the diffusion process; R is the universal gas constant; and $T_{avg}(t)$ is the running average temperature (°C) over the period of time ($t - t_0$).

The model expressed by (6) is the adopted model in the following calculations.
# 3 Modelling carbonation costs

## 3.1 Main considerations

The objective of this chapter is to present a methodology to estimate the costs for reparation of corrosion damage in reinforced concrete buildings subjected to carbonation in Europe under a changing climate.

The study will consider:

- Existing reinforced concrete buildings constructed in different times by following various standard recommendations, materials, and construction practices for each EU country.

- Several regional environmental conditions including a control case (without climate change) and two climate change scenarios.

Therefore, a simplified approach with reasonable assumptions and simplifications is proposed to carry out such a challenging study. However, the methodology could be used/adapted to include more detailed information about a given location, economic consideration, or repair technique.

The main assumptions are as follows:

- Only direct costs are considered.

- Costs are only related to corrosion initiation, i.e. when the depth of carbonation depletes the concrete cover and there is no significant loss of the cross-sectional area of the rebars.

- Inspection costs are not included in the analysis.

- Additional corrosion protection measures, such as coatings, were not applied to the buildings after construction or due to repair to prevent carbonation. It is assumed that the same concrete mixtures are used to build up the buildings and no distinction is made with regard using different concretes depending on the specific exposure sub-class or differences in horizontal and vertical surfaces. Besides, overexposure to multiple combined effects such as concrete structures exposed to chlorides from seawater, chlorides from de-icing salts, freeze-thaw, is not considered.

- The analysis focuses on reinforced concrete façades that are directly exposed to weather conditions without any specific protection. This suggests that the potential for safeguarding the surface of concrete structures from carbonation, in accordance with EN 206, through the implementation of suitable barriers like lime-based masonry mortar, ceramic tile covering, or cladding insulation materials during renovation, was not considered for the purpose of this analysis.

Patch repair is the most common technique used to repair localised corrosion damage in RC structures (e.g., BRE 2003; Canisius and Waleed 2004, Truong et al 2022, Truong et al 2023). This involves removing locally the polluted concrete cover to about 25 mm beyond the steel bars, which are then cleaned of corrosion products, and a repair material is installed. Since carbonation damage is spread on all the surface of the facades, this study assumes that repair is done by replacement of all the carbonated concrete on all the surface of the concrete façade after corrosion initiation.

The methodology considered in this study allows the assessment of a total normalized repair cost per category of buildings. It permits to consider distinct **categories of buildings** according to their construction period, durability characteristics, type of structure, building dimension and basic elements such as windows, and location in rural or urban areas. The analysis is carried out for the chosen categories of reinforced concrete buildings placed in different EU countries and subjected to specific climatic conditions, including climate change scenarios.

Firstly, the methodology estimates the total normalized repair cost per square meter, $C_{T,m}^2$. This first part of the methodology is detailed in section 3.2. For the sake of simplicity, at the stage of evaluating carbonation depth, the **buildings construction periods** are clustered into **two major groups** called **'old'** and **'recent'** associated to different durability characteristics. The group 'old buildings' aggregates all reinforced concrete buildings constructed before 2000. For the purpose of modelling corrosion deterioration over their lifetime, buildings are assumed to be built, and initially uncorroded, in 1965. The group 'recent buildings' collects the remaining buildings where ageing effects started to be considered after the construction year, assumed as 2000. More details on the considered data to define building groups are provided in Chapter 5. As outlined
# 3 Modelling carbonation costs

## 3.1 Main considerations

The objective of this chapter is to present a methodology to estimate the costs for reparation of corrosion damage in reinforced concrete buildings subjected to carbonation in Europe under a changing climate.

The study will consider:

- Existing reinforced concrete buildings constructed in different times by following various standard recommendations, materials, and construction practices for each EU country.

- Several regional environmental conditions including a control case (without climate change) and two climate change scenarios.

Therefore, a simplified approach with reasonable assumptions and simplifications is proposed to carry out such a challenging study. However, the methodology could be used/adapted to include more detailed information about a given location, economic consideration, or repair technique.

The main assumptions are as follows:

* Only direct costs are considered.

* Costs are only related to corrosion initiation, i.e. when the depth of carbonation depletes the concrete cover and there is no significant loss of the cross-sectional area of the rebars.

* Inspection costs are not included in the analysis.

* Additional corrosion protection measures, such as coatings, were not applied to the buildings after construction or due to repair to prevent carbonation. It is assumed that the same concrete mixtures are used to build up the buildings and no distinction is made with regard using different concretes depending on the specific exposure sub-class or differences in horizontal and vertical surfaces. Besides, overexposure to multiple combined effects such as concrete structures exposed to chlorides from seawater, chlorides from de-icing salts, freeze-thaw, is not considered.

* The analysis focuses on reinforced concrete façades that are directly exposed to weather conditions without any specific protection. This suggests that the potential for safeguarding the surface of concrete structures from carbonation, in accordance with EN 206, through the implementation of suitable barriers like lime-based masonry mortar, ceramic tile covering, or cladding insulation materials during renovation, was not considered for the purpose of this analysis.

Patch repair is the most common technique used to repair localised corrosion damage in RC structures (e.g., BRE 2003; Canisius and Waleed 2004, Truong et al 2022, Truong et al 2023). This involves removing locally the polluted concrete cover to about 25 mm beyond the steel bars, which are then cleaned of corrosion products, and a repair material is installed. Since carbonation damage is spread on all the surface of the facades, this study assumes that repair is done by replacement of all the carbonated concrete on all the surface of the concrete façade after corrosion initiation.

The methodology considered in this study allows the assessment of a total normalized repair cost per category of buildings. It permits to consider distinct **categories of buildings** according to their construction period, durability characteristics, type of structure, building dimension and basic elements such as windows, and location in rural or urban areas. The analysis is carried out for the chosen categories of reinforced concrete buildings placed in different EU countries and subjected to specific climatic conditions, including climate change scenarios.

Firstly, the methodology estimates the total normalized repair cost per square meter, $C_{T,m}^2$. This first part of the methodology is detailed in section 3.2. For the sake of simplicity, at the stage of evaluating carbonation depth, the **buildings construction periods** are clustered into **two major groups** called **'old'** and **'recent'** associated to different durability characteristics. The group 'old buildings' aggregates all reinforced concrete buildings constructed before 2000. For the purpose of modelling corrosion deterioration over their lifetime, buildings are assumed to be built, and initially uncorroded, in 1965. The group 'recent buildings' collects the remaining buildings where ageing effects started to be considered after the construction year, assumed as 2000. More details on the considered data to define building groups are provided in Chapter 5. As outlined
previously, no remedial measures or protective coverings on the structural components of concrete have been considered applied within the examined building stock.

Secondly, $C_{T,m}^2$ is used to compute the total normalized repair cost per category, $C_{T,cat}$. This second part of the methodology is given in section 3.3. To evaluate the surface of the building exposed to corrosion, the two groups of buildings, ‘old’ and ‘recent’, were further divided into the so-called **categories of buildings** that address characteristics such as number of stories, load-resisting systems, and type of settlement where buildings are located. $C_{T,cat}$ can be aggregated at regional, national and EU levels to estimate global costs. More details on the used parameters and data to define building categories are given in section 3.3 and Chapter 5.

## 3.2 Total normalized repair cost per square meter

### 3.2.1 Overview

Figure 2 presents the flowchart of the proposed methodology to estimate the total normalized repair costs per square meter. The inputs of the method, blue components of Figure 2 are: (i) carbonation depth, $x_c$, (ii) building characteristics (concrete cover thickness, $c_t$, and construction year), and (iii) the repair costs. The components in green are the main outputs.

The considerations for defining these site specific input variables are detailed in section 3.2.2. The carbonation depth and the building characteristics are used to estimate the probability of corrosion initiation by considering, in a simplified way, the uncertainty related with the concrete cover thickness (section 3.2.2). This probability is after used to estimate the times to repair and related costs since the construction time, or another reference time such as the current year, until 2100. Based on the surrounding environmental conditions, concrete cover and construction year, buildings could be repaired more than once during its lifetime. The number of repairs over time is identified by the index *i* in the middle green box shown in Figure 2. A total normalized repair cost per square meter is finally obtained for a group of structures built during a given period and exposed to particular environmental conditions including climate change (section 3.2.4).

<figure><img src="image_6.png" /><figcaption>**Figure 2.** Flowchart to assess the total normalized repair costs per square meter.</figcaption></figure>

### 3.2.2 Input data

#### Carbonation depth

Carbonation depths are provided by carbonation models that account for environmental conditions including climate change effects. Figure 3 presents two examples of carbonation depths used to illustrate the proposed methodology. Figure 3 was obtained using equation (1) where the carbonation coefficient, $K_c$, which is a constant parameter driving the carbonation process, is fixed at 0.5 and 0.4545 for the scenarios with and without climate change, respectively. For these values, it is observed that the carbonation depth is larger for a given time when climate change is considered. Or, for a cover depth of 3 cm, the time to carbonation initiation $t_{ini}$ is anticipated when climate change is considered, referred as $t_{ini,1}$ in Figure 3, relatively to a situation neglecting climate change ($t_{ini,2}$ in Figure 3), i.e., $t_{ini,1} < t_{ini,2}$. Different findings could be expected when more realistic models and data are considered, such as climate projections for a given location in Europe as it is discussed in Chapter 4.