Ensuring proper management of building renovation based on an optimised decision-making model: Application in schools and social housing from southern Europe.

IOP Conference Series: Earth and Environmental Science PAPER • OPEN ACCESS Ensuring proper management of building renovation based on an optimised decision-making model: Application in schools and social housing from southern Europe. To cite this article: A Serrano-Jiménez et al 2022 IOP Conf. Ser.: Earth Environ. Sci. 1078 012131 View the article online for updates and enhancements. 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Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 1 Ensuring proper management of building renovation based on an optimised decision-making model: Application in schools and social housing from southern Europe. A Serrano-Jiménez1,2*, C Díaz-López1,4 Á Barrios-Padura1,2 and M Molina- Huelva2,3 1 Department of Building Construction I. University of Seville. Reina Mercedes 2. 41012. Seville (Spain). 2 Institute of Architecture and Building Science (IUACC). University of Seville. S Reina Mercedes 2. 41012. Seville (Spain). 3 Department of Building Structures. University of Seville. Reina Mercedes 2. 41012. Seville (Spain). 4 Department of Building Construction. University of Granada. Severo Ochoa 1. 18071. Granada (Spain). *E-mail: [email protected] Abstract. One of the main challenges for architects and technicians is the efficient management of the built environment, in response to the growing deterioration and obsolescence in the building stock. This research introduces the design, development and application of a novel decision support system that assesses the multidisciplinary advantages or disadvantages of different intervention strategies, mainly focused on schools and social housing. The concept of the model aims to gather, interrelate and weight different renovation factors and variables, according to technical, social, energy and economic parameters, quantifying results on the impacts, consequences and benefits of each renovation strategy and providing practical outcomes in the design, construction, management and maintenance stages. This study uses schools and multi-family buildings, located in southern Europe, to apply and test the system iteratively in both building typologies, serving to adjust the calculation model and demonstrate its operation and replicability. The results are classified according to different intensity levels with their corresponding design alternatives along with a graphical output of results for decision-making. This model is expected to contribute to policy-making by introducing new theoretical and practical renovation guidelines, with a rational adjustment of proposals and ensuring effective and feasible action strategies in the built environment. Keywords: building stock, decision support system, building renovation, schools, social housing. 1. Introduction One of the main urban challenges, on a global and European scale, is based on guaranteeing an efficient and sustainable regeneration of the building stock, through the identification of appropriate action levels SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 2 that ensure the satisfaction and feasibility of renovation works in each context, improving the quality of life of an increasingly ageing population in the built environment [1,2]. In Europe, building renovation acquires a key role since more than 40% of existing buildings are older than 50 years, not only in housing building typologies but also in public uses, such as schools, in which more than 60% were built before 1980 [3]. This background increases the need to design new multidisciplinary assessment systems for urban regeneration and building renovation strategies, from different disciplines, that qualify and quantify the suitability of actions in the housing stock or in schools under a rationalised process [4]. Recent research studies highlight the importance of integrating social and economic criteria, together with the essential technical field, to assess efficiently the different alternatives in renovations works [5]. Moghtadernejad et al. [6] enhanced the usefulness of multi-criteria decision-making methods for architects and technicians and introduced a particular model particularly applied to façades. Riera-Pérez et al. [7] introduced a multi-criteria approach to compare different urban renewal scenarios with a graphical display of results as a mechanism that contributes to facilitate decision-making in building renovation. Serrano-Jiménez et al. [8] incorporated a specific accessibility assessment procedure for social housing with elderly occupants by using a weighting model to quantify the suitability of mobility actions through appropriateness, priority and feasibility indices. Finally, Olsson et al. [9] introduced a new approach for assessing renovation measures in order to identify appropriate target levels in early project stages for administration, giving an effective way to evaluate different strategies and introducing the factor of consequence for its valuation. Although there are numerous research studies applied to residential use in the initial stages, there is a lack of support systems for decision-making, based on multi-assessment models, that allow flexibility and openness to adapt and be transversal to the different building uses, such as schools, that belong to public administration under different socioeconomic contexts [10]. On the one hand, there are numerous existing buildings in a vulnerable and deteriorated situation that demand urban and architectural regeneration guidelines with feasible criteria [11], and also the establishment of different action levels, avoiding to always promote deep renovation works, which normally are considered unfeasible in their multiple dimensions [12]. On the other hand, various research studies highlight the lack of comfort that exists in outdoor areas and indoor environments of schools [13], which shows a demand for multidisciplinary research that provide flexible tools that could be adaptable to different building uses, along with other starting circumstances. Regarding the construction process, although the European regulations predominantly focus on optimising the energy efficiency of existing buildings [14], there are other key parameters related to the technical and construction process when deciding the feasibility of the renovation process [15]. Thus, the research starts from the premise that energy efficiency must be ensured together with a technical, economic and social viability, in the selected multidisciplinary factors, identifying advantages and inconveniences when deciding renovation strategies. This research presents the design, development and testing of a multidisciplinary assessment system of building renovation strategies that serves to facilitate decision-making and contribute to a proper management of urban regeneration, being tested both in the housing stock and existing schools from southern Europe. One of the novelties compared to other studies is the flexible and open nature of the new designed system to be applied in different building uses, by assessing 10 renovation factors based on fulfilling technical inspections and users’ interviews both in private and public buildings. The paper aims to identify and quantify an innovative weighting system to serve as decision support system by drawing together both technical and socioeconomic factors to present them in an understandable way for experts and non-experts and also by incorporating an assessment model based on 3 main indices: 1. Impact, 2. Consequences and 3. Benefits of different intervention strategies within building renovation. The paper deals with the complexity of integrating and evaluating multiple influencing factors linked to retrofitting works, taking into account that it is not possible to interpret many of these factors in a completely neutral and data-driven way. Actually, the manuscript also introduces the design of a graphical display of results that allows visualising the weighted values of 10 renovation factors and determining the choice of the most appropriate and most satisfactory strategies for each context. These SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 3 insights of this new assessment model facilitate designers and developers the adjustment of renovation proposals to each socioeconomic context in different building and thereby ensuring a proper management and maintenance of new retrofitting interventions. Once the paper introduces and justifies the topic, the following sections describe the designed methodology, the selected case studies to apply and test the model, and subsequently incorporates a numerical and graphical output of results along with their discussion according to the renovation strategies. These results and the developed methodology itself lead to methodological and particular conclusions of the research, towards highlighting the usefulness of this multi-criteria assessment model. 2. Methodology This section defines a particular assessment and decision-making model applicable to existing buildings, social housing and schools, by incorporating multidisciplinary patterns for assessing multiple renovation factors through a sensitivity analysis linked to building renovation. The innovation of the model is based on a weighting model that quantifies the benefits, consequences and impacts of different renovation strategies. To this end, it is intended to show the breadth of building uses where it could be applied and also the variety of strategies or action packages that could be designed to be assessed and quantified. Figure 1 shows a graphic outline for the procedure to be performed, including the 3 analysis items that are taken into account for each case study: Impact, Consequence and Benefit. The proposed multi-assessment model has been iteratively developed according to the technical, social, energy, and economic characterization, that are commonly obtained from the processes prior to, during and after the development of retrofitting works, involving technical visits, surveys and interviews that gather significant data and characteristics, for which it has been a continuous process of back and forth to design iteratively the weighting model and the graphical output of results. Regarding a greater explanation of the tools to be used, the research has followed and expanded the methodological resources established in previous studies [16,17], regarding the development of a technical inspection sheet that marks the state of conservation, the constructive characterization and the technical and energy evaluation of the building in its envelope and interior spaces. Moreover, it has been combined with a series of user questionnaires related to obtain the satisfaction level, on a 1-5 Likert scale, the needs and demands of users to be taken into account in the design of renovation strategies and other open-ended questions for receiving diverse information on each building daily operation. Figure 1. General outline of the procedure developed in this research. The outline details a scope of application that is especially focused on multi-family social housing, generally built before 1980, as well as schools from that same construction period, prior to national energy regulations and having served more than 40 years of service, being obsolete, deteriorated, and out of the required comfort conditions. SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 4 For the selected school and residential neighborhood, defined in subsection 2.1., a technical diagnosis has been carried out, led by architects, which has made it possible to obtain the required retrofitting actions, their corresponding investment costs, as well as other factors inherent to the required renovation works, such as the duration, energy saving simulations, waste quantification, among others, which will serve to obtain a pre-renovation assessment of each strategy. These data have been combined with users' responses to short surveys and conversations, both in schools and in residential neighborhoods. The selected factors and subcategories have been the result of gathering objective information necessary to take into account from the different disciplines, integrating different contributions of related studies in the literature review, as well as the incorporation of other complementary qualitative aspects that complete the information of diagnosis and represent an important valuation to facilitate decisionmaking in building renovation. All these factors are weighted independently in a 0-10 range for the comparison and selection of the most significant valuations according to the various circumstances in order to assume an integral approach related to the: 1. Impact, 2. Consequences or 3. Benefits. Eq.1 gathers all the variables and presents the weighting procedure for obtaining normalized values in a 0-10 range for each factor. The calculations are mainly based on assigning a score for each variable ( 𝑥 ) in relation to its possible maximum score ( 𝑥!"# ) among the different variables that make up each factor. [Eq. 1] 𝑤$=# #!"# ∗10 The factors are defined as follows: Impact | Duration is the total time expected to completely carry out the renovation work. The duration is measured from the start of the physical intervention, in terms of weeks, months, or years, until the works are completely finished and ready to service. Impact | Scale defines the size of the interventions and the place where the renovation actions are carried out, differentiating between outdoor spaces, indoor communal spaces, and inside the apartments or classrooms. For its evaluation, the results are weighted based on three action degrees: punctual, partial, and total. Impact | Technical complexity considers the complexity of the retrofitting works according to the construction techniques and the access to each architectural element or construction phase. The elements of the building are grouped as: interior partitions and room distribution (including wet rooms), technical systems (ventilation and air-conditioning), vertical communication core (staircase and lift), building envelope (façade, windows and roof), and structure and foundation. An evaluation of the complexity and techniques and complexity is obtained. Consequence | Relocation or unusable spaces takes into account possible residents’ or students’ relocation or the restricted access to certain communal or private services or classrooms during the renovation work. Various scenarios are considered regarding complete relocation, or temporarily disabled spaces are considered, and a final value is weighted. Consequence | Users’ worries measure the users’, both residents and students or teachers, perception of the renovation with respect to uncertainty and evidence-based regarding the renovation process, the possible effect on the social perception, economy or any other improvement, and the quality of the available information and communication plan through different variables that are taking into account in interviews and small surveys for obtaining a final weighted value. Consequence | Noise and nuisance from the renovation that will affect the users, such as dust, loud banging, and drilling during the renovation works. This factor focuses on recognizing the type of noise, dirt, loud knocking, and drilling and how often they occur, according to the consequences for the schools and housing daily life if relocations do not exist. Consequence | Waste production values the volume and weight of waste materials generated during the renovation process. The ranges that are defined have been limited based on specific databases, both volume and weight are equally weighted and a final value is obtained. Benefit | Energy reduction assesses the reduction of operational energy demand in kWh/m2 and a percentage for each renovation strategy. These energy saving values can be obtained by using DOE2 SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 5 simulation tools. The energy reduction is measured from its original state to after the renovation, and a weighted value for the quantity range and the percentage of reduction is obtained. Benefit | Standard improvements assess the increase in quality as compared to the initial state of the building in the form of different scores regarding Design, Accessibility, Safety, and Indoor comfort. The standard improvement factor also considers whether the renovation improvements have a permanent, seasonal, or occasional benefit according to the service, use, and operation for the users. Benefit | Visual changes value the positive or negative effect on the exterior changes with respect to architecture, aesthetics, and heritage. This parameter has been selected as a result of perceiving the social importance of visual changes in the perception of users at the end of the work, beyond other types of changes or results, visualization stimulates the provided benefit after a renovation. The quantification of this factor may be positive or negative depending on the final result, the type of changes, and the patrimonial protection in social housing or schools. The data from the school and the housing typology were gathered through technical visits and meetings with their users, trying to contact with the main responsible members of the schools and the presidents of the housing community. The research has been developed thanks to the collaboration of a research team made up of architect, as well as with a contribution of knowledge of sociologists regarding the questionnaires, the interpretation of social results and the weighting of the perceptions of the users. Therefore, this multidimensional evaluation procedure should be applicable in any other residential neighbourhood or school as a means to assess the feasibility of renovation, depending on the socioeconomic context of each location and the particular demands of the occupants. 2.1. Case studies This study presents two reference building typologies from educative centres and social housing as case studies: built before 1980, isolated blocks, with significant shortcomings in their conservation status and regulatory non-compliances with respect to current energy and comfort regulations. In both buildings their users demand certain renovation actions in order to provide better teaching and living conditions. Both reference cases have been used to verify, apply and test, and simulate the proposed model. The selected school and neighbourhood are located in the Andalusian region, in Spain, in Córdoba and Seville respectively. In Spain, where around 55% of buildings were built before 1980 [18], so there are many similar schools or residential neighbourhoods facing the same needs for renovation, thereby demonstrating and testing the usefulness of this model. Both case studies areas are defined below: A) Primary school that was originally built in 1944 and partially renovated in 1983 in the municipality of Villa del Río. The school is compound of 4 linear buildings of two storeys, entailing around 26 classrooms, with a regionalist style with sloping tile roofs and with higher towers in the extremes of each building. The main shortcomings of this building are the lack of thermal insulation, some damage due to humidity and poor quality of the materials that make up the windows and the deterioration of the wood on the roof. Figure 2 presents an aerial imagen and a generic picture of the school typology. B) Residential neighbourhood of 9 closed blocks, that are composed by 4 linear buildings with connecting links in the corner. The buildings were originally built in 1942 and partially renovated in 1976 and entail around 324 multi-family apartments. The multi-family buildings also present a regionalist style with sloping tile roofs. The main shortcomings of this building are the lack of thermal insulation, damage due to humidity, certain cracks, and an important breach in accessibility conditions and dimensions. Figure 3 presents an aerial imagen and a generic picture of the urban typology. SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 6 Figure 2. Case A. School building. Photo: Authors Figure 3. Case B. Social neighbourhood. Photo: Authors Table 1. Basic data, characterisation, and diagnosis of the school in Case A BASIC DATA Year of construction Classrooms Storeys Year of renovation Num. of users Surface area per classroom (average) Initial energy demand Case A 1944 24 Gr. + 1 1983 450 approx. 34m2 175kWh/m2 CHARACTERISATION Envelope Systems Façade: Mortar cladding, Solid brick wall (40cm) and gypsum coating. Heating: Central heating and water radiators by diesel. Roof: ceramic tile roof, cement mortar slope formation, wood structure. Cooling: No colling unless teachers’ room. Floor: Concrete slab, ceramic flooring bonded with cement mortar. Windows: Iron frames, no thermal break and glazing. Interior partitions: Hollow brick partition with gypsum boarding. Ventilation: Natural ventilation. DIAGNOSIS Technical status Deteriorated and damaged status both inside and in the exterior façade. Many fissures and damp areas in the façade. Outdated technical systems, such as heating, pipes, and radiators. Classroom layout Width original dimensions in the classrooms, considerable height and particularly big size in windows Accessibility Limited access to the top floor. Absence of a lift. Inadequate accessibility conditions outside and inside Thermal performance The transmittance values and the energy demand are very high with respect to the energy requirements Maintenance During the last 25 years, only punctual actions have been taken. There is a general lack of investment Table 2. Basic data, characterisation, and diagnosis of the multi-family building in Case B BASIC DATA Year of construction Num. of buildings Storeys Year of renovation Num of dwellings Surface per apartment (average) Initial energy demand Case B 1942 54 Gr. + 2 1983 324 approx. 69m2 154kWh/m2 CHARACTERISATION Envelope Systems Façade: Mortar cladding, Solid brick wall (24cm), air chamber, interior brick partition and gypsum coating. Heating: No heating unless electric local heating. Cooling: No colling unless particular splits. Roof: ceramic tile roof, cement mortar slope formation, concrete slab. Windows: Iron frames, no thermal break and simple glazing. Floor: Concrete slab, ceramic flooring bonded with cement mortar. Ventilation: Natural ventilation. Interior partitions: Hollow brick partition with gypsum boarding. DIAGNOSIS SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 7 Technical status Appearance of the buildings deteriorated, with loss of material, humidity and important cracks. Windows and thermal envelope outside the current energy regulations Dwelling layout Narrow and confined rooms, with small bedrooms and low headroom. Interior natural lighting is insufficient in many cases Accessibility Limited access to the dwellings through stairs, reduced useful widths and inaccessible access to the portal Thermal performance The transmittance values and the energy demand are very high with respect to current energy requirements Maintenance During the last 40 years, only punctual actions have been taken. There is a general lack of maintenance 2.2. Renovation strategies criteria Minor. Covering renovation proposals with investment costs of less than 10,000€ or 50€/m2. The interventions are usually carried out outside the dwellings or classroom: either on the envelope or in the communal outdoor areas. The renovation process does not interfere with the normal use of students or inhabitants. Moderate. Investment cost between 20,000€ and 50,000€ or between 50€/m2 and 100€/m2. The interventions are usually carried out outside or in the communal areas of the building, although specific operations inside the classrooms or apartments can also be included. The renovation slightly interferes with residents and the normal usage of the apartments. Major. Strategy that considers renovation proposals with an investment cost between 50,000€ and 100,000€ or between 100€/m2 and 200€/m2. Global interventions, such as actions that affect the entire building envelope, are considered outside the building and in indoor communal areas and can also include considerable changes inside the rooms or classrooms. The work process of these actions significantly interferes with the users’ daily use and could limit the use of certain rooms of the school or the apartment for short periods and entail the relocation of users. Deep. Strategy that covers renovation proposals with an investment cost over 100,000€ or more than 200€/m2. Integral refurbishment actions are considered across the whole building. The work is intense and would require the relocation of students or residents for a period. 3. Results This section presents the weighted results of testing the model in both case studies, providing the designed renovation strategies and their corresponding multidisciplinary performance (Table 1 and Figures 4 and 5) from different technical, social and environmental factors for each strategy and each case study. Additionally, the results will be outlined in a graphical output of values that will facilitate decision-making, being this graphical output of results tested for its future application in a digitized tool (Reprograma-tool). The proposed actions for each strategy, that can be adapted to each case study, are: Minor: 1| Repair exterior cracks, fissures, and damp patches on façades; 2| Seal window frames; 3| Repair drainage pipes and damaged parts of the tiles roof; 4| Place a ramp in the main entrance door of the school or in the portal for an accessibility improvement; 5| Adapt the main access door. Moderate: 1| Implement exterior XPS-insulation and repair the façade and roof; 2| Replace windows; 3| Adapt completely the accessibility limitations of the portal access; 4| Renovate bathrooms. Major: 1| Implement exterior XPS-insulation and repair the façade and roof; 2| Replace windows; 3| Install or replace an elevator; 4| Completely adapt portal access; 5| Renovate all wet rooms; 6| Replace central heating, radiators, and pipes. Deep: 1| Implement exterior XPS-insulation and repair the façade and roof; 2| Replace windows; 3| Install or replace lift; 4| Completely adapt to entrance and portal access; 5| Renovate wet rooms; 6| Improve rooms redistribution; 7| Replace ventilation and central heating (radiators, pipes, and ventilation ducts). Deep strategy involves the relocation of users for months, and whose costs must be considered in the analysis. Table 3. Main results weighted after having taken into account multiple renovation factors. MINOR MODERATE MAJOR DEEP IMPACT | Duration A 1.4 | 2-4 weeks 4.6 | 2-4 months 6.3 | 5-7 months 8.0 | 12 months B 2.2 | 1-5 weeks 4.4 | 3 months 6.7 | 4-6 months 7.4 | 10 months SBE-BERLIN-2022 IOP Conf. Series: Earth and Environmental Science 1078 (2022) 012131 IOP Publishing doi:10.1088/1755-1315/1078/1/012131 8 IMPACT | Scale A 2.5 | Only outside 5.6 | Partial outs. & insid. 8.1 | Total outs. & part. Inside 8.9 | Total outside & inside B 2.2 | Part out. & insid. 4.4 | Outs. & part. Insid. 6.7 | Outs. & insid. 8.9 | Total outside & inside IMPACT | Tech. complex. A 1.5 | Low - 2 phases 3.9 | Medium – 3 phases 7.1 | Medium-High - 4 phases 8.0 | Highall phases B 1.3 | Low – 1.5 phases 2.0 | Medium – 2 phases 7.7 | Medium-High- all phases 8.4 | High – all phases CONSEQ. | Relocation A 1.0 | No. Limited uses 2.1 | No. Disabled spaces 4.2 | No. Disabled classrooms 9.6 | Yes. 3-6 months B 1.8 | No. Limited acts 2.7 | No. Disabled rooms 4.4 | No. Partial. Disabled. 9.0 | Yes. 2-4 months CONSEQ. | Users’ worries A 3.5 | Disinformation 4.3 | Uncertainty & disin. 7.7 | Uncert. & partly feasible 8.0 | Uncert. & unfeasible B 3.6 | Non-priority 6.5 | Uncertainty 8.5 | Uncert. & unfeasible 9.8 | Unfeasible CONSEQ. | Noise & Nuis. A 3.2 | Occasional 4.7 | Noise & no drills 7.8 | Constant noise & drilling 9.0 | High noise & drilling B 3.3 | Occasional 5.0 | Noise & no drills 8.3 | High noise & drilling 6.6 | Relocated. Occasional CONSEQ. | Waste produc. A 2.4 | 10m3 15-20t 5.1 | 25m3 20-30t 6.9 | 40m3 80-90t 8.6 | 60m3 120-130t B 1.9 | 5m3 5-10t 4.4 | 10m3 15-20t 6.9 | 25m3 30-40t 8.1 | 40m3 100-110t BENEFIT | Energy savings A 1.8 | 5-10kWh/m2 2% 5.3 | 25-50kWh/m2 24% 7.0 | 80-120kWh/m2 41% 8.2 | Over 150kWh/m2 48% B 1.9 | 5-10kWh/m2 4% 6.3 | 20-40kWh/m2 32% 7.8 | 70-100kWh/m2 48% 8.6 | Over 100kWh/m2 55% BENEFIT | Stand. Improv. A 2.3 | D:L A:L S:- I:M 6.4 | D:M A:M S:L I:M 7.5 | D:M A:M S:M I:M 9.5 | D:H A:H S:M I:H B 1.9 | D:L A:- S:- I:M 5.2 | D:M A:L S:M I:M 8.0 | D:M A:M S:M I:H 8.4 | D:H A:M S:M I:H BENEFIT | Visual changes A 0.8 | Low-out. 7.0 | Med. Out-Low ins. 7.5 | Med. Out-ins. 8.8 | Med. Out.-High insid. B 1.1 | Low-out. & ins. 6.6 | Med. Out-ins. 8.1 | Med-High out-insid. 9.6 | High Out-High insid. Figure 4. Multidsciplinary results diagram for Case A Figure 5. Multidsciplinary results diagram for Case B 4. Discussion Table 3 and Figures 4 and 5 define the performance of each renovation strategy with respect to the 10 main selected factors, allowing a sensitivity analysis to be carried out through the graphical output of results. The results show a variation in the weighting of the results between the school and the residential neighbourhood. Although the renovation actions are the same, the impact, consequences and benefits incorporated vary according to the building use, demonstrating the operation of the model. This weighted valuation facilitates technicians, policy-makers and promoters to compare the best choice of renovation strategy for their decision-making and, consequently, in the design of the final proposal. Regarding the particular results of the school Case A, the quantitative and qualitative jump of each strategy in the final values is observed. For the minor strategy, although the impact on duration and technical complexity are very slight for the user, the benefit obtained is reduced, with low improvements in the Design (D) or accessibility (A) conditions, but with no consequences in other aspects. Likewise, a quantitative jump is observed in the moderate strategy, with valuations above 5 in the benefit parameters (5.3, 6.4 & 7.0), which shows that it can be a feasible option with medium-low impacts and