**Energy E**ffi**ciency, Thermal Comfort, and Heritage Conservation in Residential Historic Buildings as Dynamic and Systemic Socio-Cultural Practices**

**Kalliopi Fouseki \* , David Newton, Krisangella Sofia Murillo Camacho, Sohini Nandi and Theodora Koukou**

UCL Institute for Sustainable Heritage, University College London, London WC1E 6BT, UK; d.newton.12@alumni.ucl.ac.uk (D.N.); ucftkmu@ucl.ac.uk (K.S.M.C.); sohininandi@gmail.com (S.N.); tkoukou1989@gmail.com (T.K.)

**\*** Correspondence: kalliopi.fouseki@ucl.ac.uk

Received: 11 May 2020; Accepted: 3 June 2020; Published: 8 June 2020

**Abstract:** With buildings being responsible for nearly a quarter of global greenhouse gas emissions, intensive building decarbonization programs are in place worldwide, with unintended consequences for historic buildings. To this end, national and international guidance on energy efficiency for historic buildings advocate for the adoption of a 'whole house approach' that integrates heritage values in energy efficiency plans. Most guidance, though, relies on non-evidence based, pre-assumptions of residents' heritage values. And yet, unless we understand how and why residents negotiate their decisions between energy efficiency, thermal comfort, and heritage conservation, such guidance will not be applicable. Despite the urgency to decarbonize the building stock, research on how inhabitants of old buildings make such decisions is extremely limited. It is also case-study specific, often lacking the required depth. To address this gap, this paper offers the first international, in-depth study on the topic. It does so through a rigorous double-coded, thematic analysis of 59 in-depth semi-structured interviews (totaling 206,771 words) carried out in Greece, Mexico, and the UK. The thematic analysis is combined with system dynamic analysis, essential for unveiling what parameters affect inhabitants' decisions over time. Drawing on theories on the dynamics of social practices, we conclude that the process of decision-making on energy efficiency, thermal comfort improvement, and heritage conservation is a socio-cultural, dynamic practice, the change and continuation of which depends on how the following elements are connected or disconnected: materials (e.g., original features), competencies (e.g., restoration skills), resources (e.g., costs), values, space/environment (e.g., natural light), senses (e.g., thermal comfort), and time (e.g., years living in the house). The connection or disconnection of those elements will depend on (a) the nature of the context (e.g., rural, urban, conservation area); (b) the listing status; (c) age and construction materials of building; (d) local climate; and (e) ownership status.

**Keywords:** heritage values; energy efficiency; thermal comfort; heritage conservation; original features; system dynamics; social practices; decision-making; historic building

#### **1. Introduction**

It has been almost five years since the Paris Agreement on Climate Change was signed as a response to the urgent need to reverse global warming trends. The Agreement emphatically states that, if greenhouse emissions are not reduced dramatically, the global temperature will exceed 1.5 ◦C, with disastrous environmental, economic, and social consequences [1]. In Europe alone, buildings are responsible for approximately 40% of energy consumption and 36% of carbon dioxide emissions [2],

with the majority of buildings located in cities where 73% of the European population resides [3] and with 23% of the building stock dating before 1945 [4]. Although a small number of this building stock is listed, the majority of buildings are non-listed. And yet, non-listed, traditional buildings are also imbued with heritage values that may impede the implementation of certain energy efficiency interventions [5,6], or, as we will argue, inspire alternative ways of energy efficiency. Heritage, listed and non-listed, buildings, are thus a special building stock which requires a distinct approach to energy efficiency that considers both its heritage values and the needs of its users. It is within these lines that guidance on how to improve the energy efficiency in historic buildings is currently being developed at national and international level. In the UK, for instance, the 2018 Guidance on 'How to Improve the Energy Efficiency in Historic Buildings' published by Historic England (HE) asserts that one of the unintended consequences of 'getting energy efficiency measures wrong' includes, among others, 'harm to heritage values and significance' [7] (summary). To avoid unintended consequences, the Guidance advocates for a 'whole building approach' that uses the understanding of a building 'its context, its significance, and all the factors affecting energy use as a starting point for devising an energy efficiency strategy' [7] (summary). The assumption is that older buildings are significant because they add 'distinctiveness, meaning and quality to the places people inhabit, and provide a sense of continuity and identity' [7] (p. 7). On the European level, the 'European Standards on Energy Efficiency in Historic Buildings' describe the procedure of selecting appropriate measures to improve the energy performance for a given historic building [8] (p. 13). The standards apply to listed and non-listed buildings of all types and age perceived as heritage. The term 'values' in this document encompasses 'aesthetic, historic, scientific, cultural, social or spiritual' values [8] (p. 5). Although the document is intended for both listed and non-listed buildings, in reality, most recommendations are applicable only in designated heritage. For instance, the standards recommend collaboration between owners and heritage authorities clarifying that refurbishment or repairs are viewed as 'non-heritage interventions if they do not respect heritage significance that is based on evidence' [8] (p. 8). However, as aforementioned, the significant majority of old buildings are residential and not listed. As a result, it is exceptionally rare for inhabitants to consult heritage agencies before they repair or refurbish their residences. More importantly, in both documents, 'heritage values' are based on pre-assumptions reflecting the perspectives of heritage professionals rather on evidence on users' attitudes. This is due to the lack of in-depth studies on the meanings owners and occupants associate with historic buildings (listed or non-listed).

Historic England (HE) and European standards on Energy Efficiency in Historic Buildings (EN) guidance constitute two of the most recent attempts at the national and international level to address energy efficiency interventions in the context of heritage buildings. Because it is an issue that only recently is being remarked at a policy level, it is normal for these documents to have gaps that need to be filled in so that the provided guidance and standards are meaningful and impactful in the real-life world. The three main knowledge gaps that this paper attempts to start filling are: (a) lack of evidence on what exact values (social and cultural meanings) occupants of listed, as well as non-listed buildings attached to their residences; (b) how those values change over time; and (c) to what extent do changing values affect residents' decisions or energy efficiency and thermal comfort interventions. The paper will approach this question through a cross-cultural in-depth study carried out in five different geographical regions, the first of its kind. It draws on rich, qualitative data derived from 59 semi-structured interviews totaling 206,771 words, which were conducted in: (a) 'neo-classical' stone listed buildings in Athens (Greece); (b) Victorian and Edwardian brick, non-listed buildings in Walthamstow (London); (c) 1940s Swedish-type timber structures scattered in rural England; (d) listed stone buildings in the world heritage site of Mexico City; and; (e) brick, listed and non-listed, mostly Victorian, buildings in conservation areas of Cambridge. The paper does so by using the method of system dynamics, a methodological approach that results in re-conceptualizing heritage, energy, and thermal comfort as social and cultural, dynamic and interconnected practices. By thinking of heritage, energy, and thermal comfort as socio-cultural, dynamic, interconnected practices, better

guidance can be provided for the sustainable future of historic, residential buildings. By adding Mexico into the analysis, we attempt to offer a more international approach to this subject matter. Unlike the UK and Greece, where there are growing attempts to develop policies and guidance specifically on energy efficiency in historic buildings, Mexico lacks a national, comprehensive evaluation program on the environmental performance of historic buildings, and yet there are intensive efforts to contribute to the decarbonization of the built environment more generally. Mexico is member, for instance, of the Global Energy Efficiency Accelerator Program and, as such, intensive energy efficient work has taken place in Mexico City. However, this is not done through a heritage lens.

As aforementioned, there is a lack of in-depth studies regarding attitudes of inhabitants of heritage buildings towards energy efficiency. This may be explained by the fact that recruiting and interviewing residents in their premises is a time-consuming and resource-heavy process. For cross-cultural and cross-geographical studies, in particular, the involvement of local researchers is vital. Another possible reason is that the focus in studies related to energy efficiency in historic buildings has mainly been placed on the development of technical solutions (e.g., References [9–11] since, as shown above, the heritage values are perceived by professionals as a non-negotiable pre-condition upon which the guidance is shaped. Therefore, peoples' attitudes inhabiting historic building towards energy efficiency have been understudied [12]. And yet, unless users' attitudes to energy efficiency in relation to heritage values is understood, 'there are no guarantees for achieving the planned level of energy efficiency' [12] (p. 188).

Fouseki and Cassar [6] were among the first to identify the need for research that would enable understanding the dilemmas that residents of old buildings face between thermal comfort improvement, energy efficiency, and conservation of heritage features. Six years later, a growing, but still limited, number of in-depth, qualitative studies in this area has emerged (e.g., [13–17], providing a few first insights into the dynamic change of heritage values and the ways they drive or prohibit residents' choices on energy efficiency and thermal comfort. For instance, Fouseki and Bobrova [13] have shown how cultural values associated with original features decline over time as the need for thermal comfort and affordable energy become a priority, resulting in the replacement of deteriorated original features (especially original windows) by modern materials. The authors have also observed how, in recent years, this trend is reversed, especially in conservation areas or areas going through 'gentrification', where the market preference is moving towards the restoration or even replication of original building features. The limited existing studies inevitably focus on single case studies located in a confined, geographical area. More international studies are therefore needed in order to develop implementable international guidance and standards.

#### **2. Theory**

Shove et al. [18] (p. 17) argue in their book the 'Dynamics of Social Practice' that social practices emerge, persist, shift, and disappear when connections between materials, competencies, and meanings are being made or broken. Materials include things, technologies, tangible physical entities, and materials of which objects are made. Competencies connote skills and know-how techniques and meanings refer to symbolic meanings, ideas, and aspirations. Our analysis advances this premise by unveiling new critical elements affecting the interaction and continuation of two socio-cultural, systemic and dynamic practices: (1) the practice of 'valuing' and 'conserving' heritage and (2) the practice of improving the thermal comfort and energy performance of an old building. By mapping the ways in which these two practices link to each other over time, we argue that these practices emerge, persist, shift, disappear, and, occasionally, revive when connections between materials, competencies, values (meanings), space/environment, senses, time, and resources (economic, human, etc.) are being made or broken. Space and environment refer to the interior space, as well as interior and exterior environmental factors. Senses denote the sense of thermal comfort and satisfaction or lack of satisfaction with the buildings' performance. Time connotes temporal dimensions linked with the age of the building, the time already spent living or expected to inhabit the residence. Resources

refer to costs needed to implement an energy efficiency, thermal comfort improvement, or heritage conservation action. The idea that social practices are systems composed of interconnections of elements which, if broken, will affect the continuation of the system is compatible with principles of the 'whole house approach' advocated by HE. By re-conceptualizing heritage, energy, and thermal comfort as social and cultural, dynamic, and interconnected practices, we open up new avenues for future interdisciplinary and synergetic research that will move beyond isolated studies of individual components of a social system, making the research outcomes more informative for developing future national and international guidance on the decarbonization of the historic built environment.

#### **3. Methods and Materials**

#### *3.1. Selecting the Case Studies*

The main criterion for selecting the case studies was familiarization of the fieldwork researchers with the local context, personal research interests of the involved researchers, funder's requirements, and access to case studies under examination. It is worth mentioning here that this papers presents the results of ongoing research the aspiration of which is to accumulate over years of knowledge across different areas in the world. As a result, we gradually build case studies, the selection of which is proposed by the involved researchers at each time. At this stage, we are interested in diversity, hence aiming for collecting knowledge from diverse cultural and geographical settings, as well as diverse building materials. The ultimate goal is to create a global atlas of qualitative data in each specific area by bringing together local researchers from the across the globe.

### *3.2. Collecting the Data*

As aforementioned, the paper provides the first systematic and cross-cultural study of inhabitants' energy efficiency and thermal comfort mechanisms in listed and non-listed heritage buildings. It does so by drawing on a rich dataset consisted of 59 in-depth, semi-structured interviews, which totals 206,771 words. The interviews were conducted in (a) 'neo-classical' stone listed buildings in Athens (Greece); (b) Victorian and Edwardian brick, non-listed buildings in Walthamstow (London); (c) 1940s Swedish-type timber structures scattered in rural England; (d) listed stone buildings in the world heritage site of Mexico City; and (e) mostly brick Victorian buildings in conservation areas of Cambridge (Table 1).


**Table 1.** Number and time of interviews per location.

Participants in the study were recruited through 'snowballing sampling', recommended by personal contacts, and through the participants themselves. Although 'snowballing sampling' may impose issues of sample representativeness, it is one of the most suitable sampling methods for studies involving 'difficult to reach' participants [19]. In our case, entering one's private household, raises issues of safety and trust, essential for in-depth interviews. Bearing this in mind, we aimed for interviewed participants representing different age groups, ethnicities, economic status, and length of

years living in the area in order to capture the diversity of responses. The interview guide comprised of three parts. The first part aimed at understanding the cultural values (meanings) that residents attribute to their buildings. Questions were combined with 'photo production' with interviewees taking pictures of those aspects they valued the most [20]. This method enabled to delve into greater depth on the complex subject of 'values'. The second part intended to explore residents' energy efficiency and thermal comfort actions over the years. The final part investigated residents' future aspirations and attitudes towards energy efficiency (including renewable technologies) solutions experimented elsewhere. At this stage, 'photo elicitation' [20] was used by showing pictures of alternative energy efficiency means (e.g., solar tiles, wind turbines, different types of insulation, etc.). of years living in the area in order to capture the diversity of responses. The interview guide comprised of three parts. The first part aimed at understanding the cultural values (meanings) that residents attribute to their buildings. Questions were combined with 'photo production' with interviewees taking pictures of those aspects they valued the most [20]. This method enabled to delve into greater depth on the complex subject of 'values'. The second part intended to explore residents' energy efficiency and thermal comfort actions over the years. The final part investigated residents' future aspirations and attitudes towards energy efficiency (including renewable technologies) solutions experimented elsewhere. At this stage, 'photo elicitation' [20] was used by showing pictures of alternative energy efficiency means (e.g., solar tiles, wind turbines, different types of insulation, etc.).

*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 5 of 22

impose issues of sample representativeness, it is one of the most suitable sampling methods for studies involving 'difficult to reach' participants [19]. In our case, entering one's private household,

interviewed participants representing different age groups, ethnicities, economic status, and length

#### *3.3. Coding the Data 3.3. Coding the Data*

The interview data were coded on the qualitative analysis software NVivo. The data were first coded by each individual researcher separately and then by the lead author who discussed the coding with each of the researchers. By conducting double-coding, we minimized inevitable interpretation biases. Each interview was uploaded as a separate file (case) and assigned an identity code comprised of the location's name initial letter and the additive number: A (Athens) C (Cambridge), T (Timber structures), W (Walthamstow), and M (Mexico). Following the principles of grounded-theory according to which the data drive the theory [21], interview data were initially coded through an open coding process, identifying as many variables and themes as possible related to the key research questions [22]. Six hundred and eighty-two codes (nodes) were created, which were then clustered under wider themes through axial coding (Figure 1). The interview data were coded on the qualitative analysis software NVivo. The data were first coded by each individual researcher separately and then by the lead author who discussed the coding with each of the researchers. By conducting double-coding, we minimized inevitable interpretation biases. Each interview was uploaded as a separate file (case) and assigned an identity code comprised of the location's name initial letter and the additive number: A (Athens) C (Cambridge), T (Timber structures), W (Walthamstow), and M (Mexico). Following the principles of grounded-theory according to which the data drive the theory [21], interview data were initially coded through an open coding process, identifying as many variables and themes as possible related to the key research questions [22]. Six hundred and eighty-two codes (nodes) were created, which were then clustered under wider themes through axial coding (Figure 1).


**Figure 1.** Snapshot of a coding tree extrapolated from Nvivo. **Figure 1.** Snapshot of a coding tree extrapolated from Nvivo.

During the coding process, cause and effect relationships between nodes were identified using NVivo's function of relationships [23] (Figure 2). During the coding process, cause and effect relationships between nodes were identified using NVivo's function of relationships [23] (Figure 2).


*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 6 of 22

**Figure 2.** Snapshot of relationships identified on Nvivo. **Figure 2.** Snapshot of relationships identified on Nvivo.

Four types of relationships were recorded. One-directional, cause and effect, 'negative' relationships were marked in red. These relationships indicate an antithetical interrelationship between the nodes. For instance, the more the 'original features' deteriorated the less the 'perceived thermal comfort is'. One directional, cause and effect, 'reinforcing' relationships were marked in green. An example of a reinforcing relationship is the following: The 'more years a resident plans to stay in the property' (length of tenure), the more likely is to 'restore the original features'. Cause and effect, iterative relationships (loops), were marked in purple, if 'reinforcing', or in orange, if they were 'balancing'. For instance, a reinforcing loop is that the 'more the natural light', the 'bigger the space looks like', and the 'bigger the space', the 'more the natural light'. An example of a balancing loop is: the 'lower the perceived thermal comfort is', the 'more likely to insulate the roof' is, which will then improve the perceived thermal comfort. In total, 209 relationships between nodes were identified. Four types of relationships were recorded. One-directional, cause and effect, 'negative' relationships were marked in red. These relationships indicate an antithetical interrelationship between the nodes. For instance, the more the 'original features' deteriorated the less the 'perceived thermal comfort is'. One directional, cause and effect, 'reinforcing' relationships were marked in green. An example of a reinforcing relationship is the following: The 'more years a resident plans to stay in the property' (length of tenure), the more likely is to 'restore the original features'. Cause and effect, iterative relationships (loops), were marked in purple, if 'reinforcing', or in orange, if they were 'balancing'. For instance, a reinforcing loop is that the 'more the natural light', the 'bigger the space looks like', and the 'bigger the space', the 'more the natural light'. An example of a balancing loop is: the 'lower the perceived thermal comfort is', the 'more likely to insulate the roof' is, which will then improve the perceived thermal comfort. In total, 209 relationships between nodes were identified.

A list of attributes was created enabling cross-tabulations and comparisons that could further elaborate the relationships. The attributes include location, building age (19th century, early 20th century, and 1940s), construction materials (brick, stone, concrete mixed with brick, concrete mixed with stone, timber), desired thermal comfort (between 20 and 25 degrees, less than 20 degrees, more than 25 degrees), length of living in the property (1–5 years, 6–10 years, 11–30 years, more than 30 years), length of time planning to live in the property (indefinite, planning to move soon, 1–5 years), listed status (listed, non-listed, partially listed (only façade), non-listed but in a conservation/protection area), ownership status (owner, landlord, private tenant, council tenant), type of area (conservation urban area, non-conservation rural area, non-conservation urban area, world heritage area) ,and type of building (detached house, semi-detached house, terraced house, A list of attributes was created enabling cross-tabulations and comparisons that could further elaborate the relationships. The attributes include location, building age (19th century, early 20th century, and 1940s), construction materials (brick, stone, concrete mixed with brick, concrete mixed with stone, timber), desired thermal comfort (between 20 and 25 degrees, less than 20 degrees, more than 25 degrees), length of living in the property (1–5 years, 6–10 years, 11–30 years, more than 30 years), length of time planning to live in the property (indefinite, planning to move soon, 1–5 years), listed status (listed, non-listed, partially listed (only façade), non-listed but in a conservation/protection area), ownership status (owner, landlord, private tenant, council tenant), type of area (conservation urban area, non-conservation rural area, non-conservation urban area, world heritage area), and type of building (detached house, semi-detached house, terraced house, flat in block of apartments).

#### flat in block of apartments). *3.4. Mapping the Data through System Dynamics*

*3.4. Mapping the Data through System Dynamics*  Based on our theoretical assumption that a decision process on heritage conservation, thermal comfort and energy efficiency improvements is a socio-cultural, dynamic, and systemic practice, we applied system dynamics in order to unfold the dynamic interconnections of the components mobilized during this decision-making process. The method of system dynamics is commonly utilized to explore the dynamic interconnections of the components of a system [23]. The term implies a 'complex entity' consisted of interconnected elements which change over time. This 'entity' can be a social practice, a building, a city, etc. The underlying premise is that changes on any of those Based on our theoretical assumption that a decision process on heritage conservation, thermal comfort and energy efficiency improvements is a socio-cultural, dynamic, and systemic practice, we applied system dynamics in order to unfold the dynamic interconnections of the components mobilized during this decision-making process. The method of system dynamics is commonly utilized to explore the dynamic interconnections of the components of a system [23]. The term implies a 'complex entity' consisted of interconnected elements which change over time. This 'entity' can be a social practice, a building, a city, etc. The underlying premise is that changes on any of those elements will affect the entire system [24] because a complex system comprises non-linear, multiple, interconnected loops

which change over time, with some loops disappearing or re-appearing under certain conditions [25] (p. 107). The loops are cause and effect relationships [26] (p. 120) which can exponentially grow (reinforcing loops) or start declining bridging the gap between a desired and an actual goal (balancing loops) [25] (p. 133). The cause and effect relationships identified in the previous research stage were mapped on Vensim, creating a causal loop diagram [26] (p. 119). Each cause-effect relationship is indicated with + or − depending on whether the relationship is positive and reinforcing (e.g., the more . . . the more) or balancing (e.g., the more . . . the less). The diagram presented here (Figure 3) is the aggregate (summative) representation of the dynamic interrelationships identified during our analysis. In other words, the diagram does not illustrate all 209 relationships, as this would be too complex to communicate in one diagram, but an aggregate version which summarizes variables (for instance, all original features are depicted as one variable) and illustrates the most common thermal comfort, energy efficiency, and heritage conservation actions. interconnected loops which change over time, with some loops disappearing or re-appearing under certain conditions [25] (p. 107). The loops are cause and effect relationships [26] (p. 120) which can exponentially grow (reinforcing loops) or start declining bridging the gap between a desired and an actual goal (balancing loops) [25] (p. 133). The cause and effect relationships identified in the previous research stage were mapped on Vensim, creating a causal loop diagram [26] (p. 119). Each causeeffect relationship is indicated with + or − depending on whether the relationship is positive and reinforcing (e.g., the more…the more) or balancing (e.g., the more…the less). The diagram presented here (Figure 3) is the aggregate (summative) representation of the dynamic interrelationships identified during our analysis. In other words, the diagram does not illustrate all 209 relationships, as this would be too complex to communicate in one diagram, but an aggregate version which summarizes variables (for instance, all original features are depicted as one variable) and illustrates the most common thermal comfort, energy efficiency, and heritage conservation actions.

*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 7 of 22

**Figure 3.** Color scheme: Senses = red; Materials = purple; Values = pink; Resources = grey; Time = yellow; Competencies = green; Space/environment = orange. The green arrows are purely used for communication purposes as they intersect other communicating arrows. Variables linked directly to heritage are filled in grey. R signifies reinforcing loops and is colored in purple, while B (in orange) refers to the balacing loops. The symbol + indicates the reinforcing relation (the more … the more), while the symbol – indicates a balancing relationship (the less … the less). **Figure 3.** Color scheme: Senses = red; Materials = purple; Values = pink; Resources = grey; Time = yellow; Competencies = green; Space/environment = orange. The green arrows are purely used for communication purposes as they intersect other communicating arrows. Variables linked directly to heritage are filled in grey. R signifies reinforcing loops and is colored in purple, while B (in orange) refers to the balacing loops. The symbol + indicates the reinforcing relation (the more . . . the more), while the symbol – indicates a balancing relationship (the less . . . the less).

#### **4. Results 4. Results**

#### *4.1. Residents' Social and Cultural Values towards Their Historic Residences 4.1. Residents' Social and Cultural Values towards Their Historic Residences*

Figure 3 depicts the aggregated, dynamic interconnections of the main factors influencing inhabitants' decisions on thermal comfort and energy performance interventions in conjunction with the heritage values they attach to their residences. A detailed presentation of each segment of the Figure 3 depicts the aggregated, dynamic interconnections of the main factors influencing inhabitants' decisions on thermal comfort and energy performance interventions in conjunction with the heritage values they attach to their residences. A detailed presentation of each segment of the diagram follows below.

diagram follows below. The reinforcing relationship 1 (R1), which lies at the center of the diagram, indicates that the more the 'original features' the higher 'the heritage value' attached to the building (Figure 4). A wide The reinforcing relationship 1 (R1), which lies at the center of the diagram, indicates that the more the 'original features' the higher 'the heritage value' attached to the building (Figure 4). A wide array of

heritage values emerged, which were clustered into three groups including: (a) values attached to the interior of the house; (b) the exterior of the building; and (c) overarching values (Figure 5). As expected, the responses vary among geographical areas, including areas located in the same country. While in current guidance documents it is mainly certain external features of an old building (such as façade, windows) that are implicitly prioritized for heritage conservation, the interviewees assign cultural and social values to a diverse range of exterior and interior architectural features (Figure 5). In the case of Swedish timber houses in rural England, for instance, it is the timber structures that residents resist to change 'because it is heritage' (T1). In Cambridge conservation areas, on the other hand, we observe that heritage conservation priorities align with those imposed by the listing system (such as original windows and original fittings). In Walthamstow, Mexico, and Athens, it is 'the high ceilings . . . ' allowing 'lots of light' and the resulting feeling of spaciousness as new 'buildings press you down' (A4). It is worth noting here that the respondents in Mexico did not prioritize specific individual architectural features as the most important, other than the spaciousness attributed to the high ceilings. country. While in current guidance documents it is mainly certain external features of an old building (such as façade, windows) that are implicitly prioritized for heritage conservation, the interviewees assign cultural and social values to a diverse range of exterior and interior architectural features (Figure 5). In the case of Swedish timber houses in rural England, for instance, it is the timber structures that residents resist to change 'because it is heritage' (T1). In Cambridge conservation areas, on the other hand, we observe that heritage conservation priorities align with those imposed by the listing system (such as original windows and original fittings). In Walthamstow, Mexico, and Athens, it is 'the high ceilings …' allowing 'lots of light' and the resulting feeling of spaciousness as new 'buildings press you down' (A4). It is worth noting here that the respondents in Mexico did not prioritize specific individual architectural features as the most important, other than the spaciousness attributed to the high ceilings. (such as façade, windows) that are implicitly prioritized for heritage conservation, the interviewees assign cultural and social values to a diverse range of exterior and interior architectural features (Figure 5). In the case of Swedish timber houses in rural England, for instance, it is the timber structures that residents resist to change 'because it is heritage' (T1). In Cambridge conservation areas, on the other hand, we observe that heritage conservation priorities align with those imposed by the listing system (such as original windows and original fittings). In Walthamstow, Mexico, and Athens, it is 'the high ceilings …' allowing 'lots of light' and the resulting feeling of spaciousness as new 'buildings press you down' (A4). It is worth noting here that the respondents in Mexico did not prioritize specific individual architectural features as the most important, other than the spaciousness attributed to the high ceilings.

*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 8 of 22

*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 8 of 22

5). As expected, the responses vary among geographical areas, including areas located in the same

country. While in current guidance documents it is mainly certain external features of an old building

**Figure 4.** Reinforcing relationship (R1) between original features and heritage values. **Figure 4.** Reinforcing relationship (R1) between original features and heritage values.

**Figure 5.** Most valuable heritage aspects across different regions related to the interior and exterior of **Figure 5.** Most valuable heritage aspects across different regions related to the interior and exterior of the buildings. **Figure 5.** Most valuable heritage aspects across different regions related to the interior and exterior of the buildings.

Original plastering Original roof Original windows

the buildings. The variation on the values attached to different heritage elements is striking (Figure 6). In Cambridge, the most predominant values are 'aesthetics' and 'originality'—echoing the values of the The variation on the values attached to different heritage elements is striking (Figure 6). In Cambridge, the most predominant values are 'aesthetics' and 'originality'—echoing the values of the The variation on the values attached to different heritage elements is striking (Figure 6). In Cambridge, the most predominant values are 'aesthetics' and 'originality'—echoing the values of the listing process. C12, for instance, notes how they endeavored to maintain all original features, including "the original stained glass . . . the original paneling and also the circle in the middle of the door. And it's

really beautiful". Contrarily, in the case of timber Swedish houses in rural England, it is the 'uniqueness' of the timber structure and feelings of 'nostalgia' evoked by the presence of the fireplace: "I always liked the open fire as we all sat around the fire" (T2). In Athens, the neoclassical buildings reminiscence a lifestyle that is now lost in a densely inhabited city. In Walthamstow, interviewees noted a sense of moral responsibility and ethical guardianship towards the preservation of certain original features: "Well, like I said, I suppose it's because, I don't know, it kind of puts you back, in touch with kind of the house it was meant to be, it just kind of feels right" (W6). Interestingly, in Athens and Walthamstow, interviewees described the building as a living body the 'character' and 'soul' of which needs to be respected: "There is a comfort of space, all the rooms are easily accessible. It was built with love and it has its own soul" (A6). including "the original stained glass …the original paneling and also the circle in the middle of the door. And it's really beautiful". Contrarily, in the case of timber Swedish houses in rural England, it is the 'uniqueness' of the timber structure and feelings of 'nostalgia' evoked by the presence of the fireplace: "I always liked the open fire as we all sat around the fire" (T2). In Athens, the neoclassical buildings reminiscence a lifestyle that is now lost in a densely inhabited city. In Walthamstow, interviewees noted a sense of moral responsibility and ethical guardianship towards the preservation of certain original features: "Well, like I said, I suppose it's because, I don't know, it kind of puts you back, in touch with kind of the house it was meant to be, it just kind of feels right" (W6). Interestingly, in Athens and Walthamstow, interviewees described the building as a living body the 'character' and 'soul' of which needs to be respected: "There is a comfort of space, all the rooms are easily accessible. It was built with love and it has its own soul" (A6).

*Atmosphere* **2020**, *11*, x FOR PEER REVIEW 9 of 22

listing process. C12, for instance, notes how they endeavored to maintain all original features,

**Figure 6.** Comparison of heritage values among the different regions **Figure 6.** Comparison of heritage values among the different regions

Moreover, an interesting variation was observed between the set of values related to the exterior (what is seen from the outside) and the interior of the house (what is experienced inside), especially in Mexico, Walthamstow, and rural England, where 'aesthetic' and 'architectural values' of the façade are the most referenced values. However, 'coziness/homeliness' and social values are mostly referenced and relate to the interior of the building. This variation explains why inhabitants in these areas tend to prioritize the preservation of original features that evoke such feelings (such as fireplaces), while they are inclined to replace features, such as windows, with modern ones in order to improve thermal comfort and energy efficiency (Figure 7). Moreover, an interesting variation was observed between the set of values related to the exterior (what is seen from the outside) and the interior of the house (what is experienced inside), especially in Mexico, Walthamstow, and rural England, where 'aesthetic' and 'architectural values' of the façade are the most referenced values. However, 'coziness/homeliness' and social values are mostly referenced and relate to the interior of the building. This variation explains why inhabitants in these areas tend to prioritize the preservation of original features that evoke such feelings (such as fireplaces), while they are inclined to replace features, such as windows, with modern ones in order to improve thermal comfort and energy efficiency (Figure 7).
