A portrait of Italian ‘Family houses’: diversified heritage in a redefined territorial and demographic context

The ‘family house’ has played a major role within the urbanisation processes that have been transforming the Italian landscape since the 1960s. It is a common feature of the widespread settlements that are part of what has been labelled the ‘diffuse city’ and was the subject of numerous studies during the 1990s. More than 20 years later, this paper returns to the topic of the Italian family house using a renewed methodological approach to describe relevant changes. The hypothesis here is that in order to grasp the tensions affecting ‘family houses’ in today’s context of demographic transition and increased imbalances between dynamic and declining areas, and to contemplate their future, the qualitative gaze adopted by scholars in the 1990s must be integrated with other investigative tools, focusing on demographic change, uses, and the property values of buildings. Using this perspective, the paper provides a series of ‘portraits’ rooted in four meaningful territorial contexts, portraits which may help scholars to redefine their imagery associated with family house and be useful for dedicated building policies.


Introduction: diffuse urbanisation in Italy-a country of 'family houses'
The 'family house' is the main element of the so-called 'diffuse city' in Italy. As known, this is a form of urbanisation that mostly developed during the 1970s and 1980s, characterised by low-density building expansions dispersed over a territory already largely equipped with infrastructure (Indovina 1990(Indovina , 1999Boeri and Lanzani 1992;Secchi 1996Secchi , 2005. Beyond regional differences, this phenomenon can be interpreted as a sign of sweeping change in the country's socio-economic conditions, in which a specific culture of living took shape (Dematteis 1991;Clementi et al. 1996). This was due to an endogenous process of densification rather than the decentralisation of large cities. The territory was progressively occupied by many small buildings, the result of building initiatives run by the families and businesses already settled there who needed more housing and other spaces, often for work-related activities. Through this process of individual mobilisation and the continuous reuse and adaptation of social fixed capital-the main roads linking major centres, and the widespread network of minor routes, agricultural ditches, and canals-the 'diffuse city' took shape in Italy with a greater intensity than in other European countries (Paone 1994;Bekaert and de Geyter 2002;Segal and Verbakel 2008;Grosjean 2010;Fregolent et al. 2013).
In the territorial framework summarised above, the family house plays a priority role in the life plans of Italian families and intertwines with peculiar welfare models (Tosi 1987;Allen 2006;Poggio 2012). Since the early years of post-war reconstruction, policies supporting private initiatives have assigned a more marginal role for public housing, and Italy increasingly became a country of homeowners. The growing percentage of families that own their home is indicative-up from 40% in 1951indicative-up from 40% in to 70% in 1991indicative-up from 40% in (Baldini 2010. A significant share of the new buildings were family houses, which become the dominant model in the 1960s-1990s 1 (Fig. 1). In this 30-year period over 5,600,000 new buildings were built, of which more than 4,100,000 were family houses (Table 1). In 2011, about 10,300,000 people resided in family houses (Table 2). This trend declined after the 1990s: the rate of construction of family houses dropped significantly, and in 2001-2011 approximately 575,000 new houses were built, slightly higher than 1/3 of the 1,555,000 built in the period 1971-81. But what kind of space is this? A 'family house' is a one or two-storey building, usually in the middle of a fenced plot, which may contain a small vegetable garden and accessories, such as garage or tool shed. It is characterised by disparate architectural styles, typological and constructive variations attributable to the use of traditional materials and techniques, and different combinations of domestic spaces and workspaces. It is the core element of a building that has often grown in a discontinuous and fragmentary manner. It is particularly versatile and can be found in different types of settlement: the margins of pre-existing urban centres, in urbanised ribbons along major roads, or in seasonal or tourist areas of coastal urban areas.
There are several reasons for the success of this housing model. It responds to the needs of a society traditionally based on the extended family, where children often reside close to their parents and where the house is the main asset handed down from one generation to the next (Saraceno and Naldini 2007;Poggio 2008). Through the support guaranteed by cohesive family networks, the availability of technical skills, and mobilisation of small capital which could be deferred over time, a family house is built and then gradually adapted, according to the family's growth and transformation. Incorporating work or hobby areas, splitting up or enlarging housing units to respond to family changes (for example, by creating housing for elderly parents or for a new young couple), to change layouts to accommodate new habits (additional room, tavern, laundry, and extra garage- Fig. 2): all this has played an important social role and has created significant economic advantages (Giriodi and Robiglio 2001;Munarin and Tosi 2001). 2 This need for adaptability of the home has been associated with a more general redefinition of the lifestyles of large portions of Italian society. In this respect, two aspects must be mentioned. Firstly, growing use of Fig. 1 The weight of one-and two-interior buildings out of the total residential stock. The curve trend shows the evolution up to 2011, and the most intense growth phase of the family house in the 1960s-1980s period (authors' calculations on data from Istat census). . The data on the resident population is also available for each combination. In this way it is possible to analyse and map the development trajectory of buildings with one and two housing units in the last century, and in particular in the period 1961-1991. vehicles implies more extensive use of the territory and makes houses that are further from dense urban centres more attractive. The family house can thus be more 'distant' , becoming one element in an articulated network of work, personal services, and leisure time. Secondly, the idea of domestic space is redefined, mixing a desire for progressive emancipation from a rural condition with the distance from a tiring and chaotic urban condition considered unsuitable for families. This idea identifies the family house as the best place to raise children. To live in a detached house that the family owns, with adequate space, a garden, and an integrated workspace for the family entrepreneurial activity has been a widespread aspiration for a long time. This reflects a complex mix of values, including economic benefits, privacy, proximity to nature, customisation of one's living space, social status, and social affirmation (Vallerani and Varotto 2005; Merlini 2009; Rolfo 2010). As we will see, the economic and social crisis that is affecting the country is having particularly intense effects on this specific form of urbanization. This implies a revision of the methodological approach, which must go beyond a sufficiently consolidated reflection on settlement and morphological aspects, to focus on the complex relationships between the economic and demographic changes of society, the material conditions and use of buildings, and the system of symbolic and economic values that concern them. In this perspective,  (Zanini 2012) the text articulates into two main passages. First of all, we draw an overall picture of the patrimony of family houses in Italy, according to different territorial geographies (paragraph 2). This overall picture is then followed by four portraits of more circumscribed situations, which integrate direct observation, processing of census data and interviews with real estate operators (paragraph 3). 3 The 'family house' today-a vast heritage, with an articulated geography Compared to the phase described above, the physical, economic and social conditions of the country have changed considerably: economic crisis, demographic change and environmental degradation processes have had a profound impact on many parts of the 'diffuse city' (Zanfi 2011;Lanzani 2012;Savino 2017;Fregolent and Vettoretto 2017a;Viganò et al. 2018). Within this framework, the current stock of family homes is substantially stable from a quantitative point of view but is subject to significant changes in meaning. The aging of the population, the shrinking of households, the redefinition of housing preferences especially by the younger population who are looking for less expensive solutions in more equipped and accessible contexts (Censis/Nomisma 2016; Filandri et al. 2020), as well as the building overproduction granted by urban plans are all factors that now challenge the maintenance and traditional adaptability of the family house (Lanzani and Zanfi 2010).
To better understand its trajectories, however, it is necessary to observe both the national picture and-as will be seen in par. 3-some more specific situations. With regard to the entire Italian territory, it is possible to make two main observations. The first concerns the prevalent location of family houses outside big cities (Fig. 3). As of 2011, almost 39% of the one-and two-interior buildings built in the 1961-90 period (thus falling within our definition of the 'family house') are located in small and medium-sized municipalities of between 2000 and 10,000 inhabitants. In these municipalities, out of a total of approximately 2,000,000 buildings, 1,600,000 are family houses. The percentages in the larger municipalities are more contained: 18.5% are found in municipalities of between 10,000 and 20,000 inhabitants, and only 10.6% in municipalities with a population of over 60,000. The substantial extraneousness of the family house to the main urban centres, even in the long term, naturally constitutes an important element.
Recognizing the end of a phase of more intense building growth must not lead one to underestimate the existence-and not infrequently the criticality-of large parts of the Italian territory in which important portions of the population still live.
A second consideration regards the plural nature of diffuse urbanization (Fig. 4). Very briefly, four different territorial situations can be recognized, in which the family house has played different roles in the past-and will be able to play in the future (Dematteis 1996;Lanzani 2003;Lanzani et al. 2015).
First of all, the regions where the family home is part of a general process of metamorphosis of the countryside (a central-north-eastern area that includes parts of Veneto, Friuli, Lombardy, Emilia and lower Piedmont, parts of Tuscany, Umbria, Le Marche, and Puglia). These are those portions of a widespread city that have incorporated small pre-existing urban centres, organizing themselves in open and diluted reticular forms in the territory, and in which the system of small and mediumsized enterprises organized according to district models once played a crucial role, but today struggle to cope with the ongoing economic crisis (Brusco 1982;Sartore 1988;Munarin and Tosi 2001; De Marchi and Grandinetti 2014; Fregolent and Vettoretto 2017b). Secondly, the contexts in which the presence of family houses is mainly attributable to the attractiveness of the valley floor and the progressive exodus from the most remote mountain territories (in the eastern part of the country, in the Alpine belt or in the Apennine belt of Le Marche and Abruzzo). The peculiarity is in this case in the relationship between diffusion and concentration: often, populations have abandoned isolated hill or mountain villages and 'gone down to the valley' who gave shape to linear urbanizations. Congestion and/or underutilization of some sections of the networks, the difficulty of maintaining infrastructure, fragmentation of the rural landscape, and ecological damages are among the phenomena emerging today (Fuà and Zacchia 1983;Pavia 2000;Merlini 2009).
The third type of territory contains extensive urbanizations that originate mainly due to phenomena of residential and productive decentralization from the main cities (in particular in the north-west, around Milan and in some cities of Padania, around Rome and Campania). The search for housing options other than the congested and more expensive ones offered by the big city has prompted in this case a myriad of real estate transactions-including the private construction of the family home-that gives shape over time to dense and articulated conurbations, which establish increasingly complex relationships of autonomy and dependence in the metropolitan areas to which they gravitate (Boeri et al. 1993;Turri 2000;Balducci et al. 2017).
The final type of territory involves the development of extensive and heterogeneous coastal urbanizations (on the Tyrrhenian and Adriatic sides and on the major islands), which result from a variety of dynamics: extensions of already established tourist centres; unitary property transactions that colonize stretches of the coast; densification around certain infrastructure nodes; and the formation of large expanses of second homes. Especially in the South, landscapes of houses characterized by seasonal forms of use and economies have developed in this way. Here, the family house, often built illegally and linked to the remittances of Italian emigrants, is part of an urbanization essentially devoid of networks and public services (Bellicini 1990;Nocifora 1994;Zanfi 2013).
Today, these four main territorial situations can be combined with as many different evolutionary trajectories, related to the redefinition of district economies, to the new territorial hierarchies around the main cities, or to changes in tourism. The growing polarizations of the real estate market reflect these specificities: on the one hand, areas of the country where new, more attractive and dynamic centralities are outlined, and on the other, areas that lose value and become increasingly marginal (Camagni et al. 2002;Bertuglia et al. 2003;Calafati 2014).

Signs of a crisis? Changing trajectories in four territorial situations
In the light such processes, it may be useful to closely re-observe the family house stock. The present analysis focuses on four sample territories-Lombardy, Veneto, Le Marche, and Puglia-which offer representative samples of the variety described above. 4

Northern Brianza, Lombardy
The first sample focuses on the northern sector of the Milanese region and spans the provinces of Como and Monza-Brianza. Since the early twentieth century, the area has had a strong manufacturing sector, mostly based on furniture production. Beginning in the 1960s, the small historic centres experienced widespread growth, with some merging. This gave birth to a heterogeneous and extensive conurbation that incorporates historical centres, low-density residential neighbourhoods, productive settlements, shopping and service clusters, residual unbuilt spaces, wasteland, and infrastructure. Family houses constituted the primary response to the endogenous demand for new dwellings. The typical spatial pattern features low-density fabrics of family houses surrounding historical centres, frequently embracing compact, productive plants or community properties such as schools, sports facilities, churches (Fig. 5a).
The most common family house type in the area is the villetta. This is a building up to 200 m 2 on two floors, standing on a property of up to 400 m 2 , with a private garden and sometimes a workspace or other small accessory buildings (Fig. 5b). Less common but also popular is the villa. This is a house larger than 250 m 2 , with a garden up to 5000-7000 m 2 , a large underground floor, and possibly a swimming pool.
In 2011, the share of family houses within the sample area (Fig. 6a) constituted 50.6% of residential buildings, and were maintained in a very good (46%) or good (43%) state, with only a minor share in a mediocre (10%) and bad (1%) condition (Istat 2011). In the census blocks where the share of family houses was above the 50% of the housing stock, the resident population in 2011 consisted of 102,000 people (71.3% of the sample population), with a slow growth trend in the 1991-2011 period (Istat 2011). At the same time, the census blocks showed a more evident ageing trend when compared to the provincial averages for the sample location, and a more limited pattern related to a higher percentage of foreign origin residents (Fig. 6b).
If we consider the local real estate market, family houses make up 10% of the houses sold in the area. The demography is marked by an ageing population, and a shift in the housing preferences on the part of younger generations, who prefer smaller single floor apartments with no garden located in more central and betterequipped environments (this trend increasingly affects elderly empty-nest owners too). The villetta and the villa have different features in this framework.
The villetta still seems to fulfil a demand deriving from young middle-class families. On average, these are two-income families with young children. Such families look for detached houses with a garden and buy oldbuild family houses, as they cannot afford to buy new homes. The family houses do not exceed 1200-1300 €/ m 2 and can be renovated with an additional expenditure of € 30,000-50,000, up to a total investment of up to € 300,000. There is still a market for these buildings, but they do not have high values within the local real estate context (OMI 2019; Immobiliare 2019).
The situation is different for villas, particularly since 2008, as the market has radically changed: 'Nobody here wants to manage villas with extensive gardens anymore because they are too expensive; moreover, elderly people are afraid to live in houses where they are isolated. It is not just a question of price: it is just a type that no longer meets demand. 5 For this second type, it is plausible to foresee a severe devaluation.

Central Veneto
The second sample focuses on the central part of the Veneto region within the Provinces of Padua and Venice. This is an area which has experienced robust economic growth since the 1970s, linked with the development of small and medium-sized dynamic enterprises organised on a district basis, mostly in the manufacturing and textile/clothing sector. A territorial structure dating back to the Roman aggeratio, and the rural roads and canals inherited from the twentieth-century land reclamations created the premises for a twofold urbanisation process. On the one hand, this consolidated the small historical centres through new additions and allotments. On the other, it created linear settlements along with the road network, in which small-size agricultural farms and rural houses alternate with industrial sheds, warehouses and commercial buildings, collective services, and family houses (Fig. 7a).
Family houses in this area have a practical and straightforward design, without architectural refinements. Their typology is typical of the 1970s and 1980s, with double rooms and two bathrooms, on average 200 m 2 . They extend along the ground and first floors, with a multipurpose basement (the taverna or cellar). On the ground floor, they often incorporate warehouses, shops, or spaces for craft activities which are linked to the family business. Plots are on average, 400-500 m 2 . and include an outdoor recreational space, parking space, and a vegetable garden (Fig. 7b).
Within the sample under analysis (Fig. 8a), in 2011, family houses constituted 66.5% of the residential buildings, and were mostly maintained in a very good (44%) or good (44%) state, with only a minor share in mediocre (11%) or bad (1%) condition (Istat 2011). In the census blocks where the share of family houses was above the 50% of the housing stock, the resident population in 2011 consisted of 32,700 people (83.6% of the sample population), with a stable growth trend in the 1991-2011 period (Istat 2011). At the same time, these census blocks showed an aging trend which is slower than the provincial averages, while a stronger trend related to the presence of resident population with a foreign nationality (Fig. 8b). If we consider the local real estate market, family houses make up a significant share (40-45%) of the houses sold, a percentage that has remained stable in recent years.
These houses, in this rural but at the same time industrialised territory, still seem to meet demand. Young people express a desire for an individual house to establish a family, and the affection for this type of building is still active even among the elderly. 'It is quite a wealthy population, with a stable demography. There are jobs in the area, and there is this idea of keeping home and work close one to each other, so there is no reason to move 6 (such a dynamic economy may explain the high share of immigrants who are more likely to inhabit the less expensive segment of the residential stock).
This attitude feeds a market of old family houses-new buildings are rare-with values between 1100 and 1500 €/m 2 (OMI 2019; Immobiliare 2019). It also supports a widespread building maintenance industry, whose operations range from the usual care of façades, fences, and gardens, to the rebuilding of roofs with the installation of photovoltaic systems or adjustments/extensions to make the house meet new family needs. 'It is a local population which is closely tied to the home; there is interest in maintaining the family capital and managing it well. 7

Valley of the river Chienti, Le Marche
The third sample is in the Marche region and lies along the valley of the river Chienti, which runs inland across Macerata Province. The area offers a typical example of the 'peripheral growth' that affected central and northeastern sectors of the country starting the 1970s, following a development model based on the industrial district. The territorial outcomes of this endogenous and locallyrooted development model included the rise of light industry scattered over the territory, with a marked presence of small family-based enterprises, and growing specialisation in textiles, footwear, and light manufacturing. In this framework, family houses have scattered throughout the network of pre-existing rural roads, sometimes in continuity with old farmhouses, and featured unusual solutions for integrating living and working spaces.
Houses are frequently directly adjacent to Provincial or Municipal roads: when they're adjacent to pre-existing inhabited centres, they are grouped in linear and continuous settlements; when they're outside built-up areas, they remain more scattered and isolated (Fig. 9a). Buildings are mostly two-storey, about 200-300 square metres, with plots ranging from 500 to 1000 m 2 . These houses often feature a workspace on the ground floor (an additional space with a surface area ranging from 100 to 400 m 2 .) originally conceived to host crafts connected with the family business (Fig. 9b).
Within the sample under analysis (Fig. 10a), in 2011, family houses constituted 75.1% of the residential buildings, and were mostly maintained in a good (49%) or very Fig. 6 a Lombardy, Northern Brianza, 10 × 10 km sample. Percentage of one-and two-interior buildings built in the period 1961-1991 out of the total residential stock at 2011 (authors' calculations on data from Istat census). b Lombardy, Northern Brianza: trends in the elderly and foreign resident population within the census blocks where family houses constitute more than 50% of the total housing (authors' calculations on data from Istat census) good (38%) state, with only a minor share in mediocre (12%) or bad (1%) condition (Istat 2011). In the census blocks where the share of family houses was above the 50% of the housing stock, the resident population in 2011 consisted of 19,500 people (73.7% of the sample population), with a faint growth trend in the 1991-2011 period (Istat 2011). At the same time, the census blocks showed a slightly stronger ageing trend when compared to the Macerata Province averages and a much stronger trend related to the presence of resident population with foreign nationality (Fig. 10b).
If we consider the local real estate market, family houses make up a relatively low share of the sold stock (80% of the market is made up of apartments), and they find it increasingly challenging to meet demand. The ground floor workspaces have often lost their original use, since the most craft activities have moved to more accessible and equipped industrial areas, and only sometimes, depending on their location and size, has it been possible to convert them for commercial or residential functions. Housing demand has then changed. Dynamic coastal settlements, which offer a more urban environment and more compact residential solutions, contrast with smaller inland centres, characterised by weak markets and further penalised by the earthquakes that hit them between 2016 and 2017. Family houses manage to meet demand only if located in close proximity to centres, or in quality landscapes that allow for tourist and recreational exploitation: 'No one wants to stay in the country anymore, with the gravel road to get home, without a drinking water and gas network. 8 A change in preferences that is reflected, on the owners' side, by frequent situations of retired empty-nesters, who have to face high management costs for large houses and gardens, and who frequently try to sell their family properties to move into apartments of 70-80 m 2 in urban centres. This mismatch between supply and demand translates into a relatively limited value of family houses-especially if we compare them with other more compact types of dwelling-hardly exceeding € 200,000 for 200-250 m 2 houses (OMI 2019; Immobiliare 2019).

Salento, Puglia
The fourth sample is located in the Puglia region and focuses on a coastal portion of the Salento peninsula, in the Province of Lecce. It includes a sequence of coastal settlements-the Marine-that developed beginning in the 1960s to 1980s as second-homes linked to the urban centres a few kilometres inland. They mostly derive from unauthorised building processes, which took advantage of previous rural roads and parcelling schemes inherited from the 20th-century land reclamation and Agrarian Reform, and generated dense, disordered and poorly serviced clusters of seasonal houses. Here family houses played several roles. They are proof of individual status (the 'dream' of a house by the sea attracted the remittances of Apulian migrants from abroad). They served as secondary residence in which a part of the extended family could spend the hot summer months. It was a space that could be rented during the tourist season, providing a supplementary income for the informal family economy.
Houses are organised in dense allotments along narrow and unpaved roads, which extend from the provincial coastal road to the shoreline (Fig. 11a). Buildings extend on one or two floors, with an average surface of 150-200 m 2 , single parcels range from 300 to 400 m 2 , they're often fenced by tall stone or cement walls. These are simple buildings, frequently self-built with cheap materials and without following any architectural plan, and they are devoid of any public network, except electricity. Public space is rare, and the overall urban quality of the settlements is very low (Fig. 11b).
Within the sample under scrutiny (Fig. 12a), in 2011, family houses constituted 81% of the residential buildings, and were maintained in a good (54%) very good (2%) state, with a significant share in mediocre (43%) or bad (1%) condition (Istat 2011). In the census blocks where the share of family houses was above 50% of the housing stock, the resident population in 2011 consisted of just 1162 people, (98.3% of the sample population), confirming the enduring seasonal character of the settlements. In the 1991-2011 period, these census blocks showed a declining ageing trend if compared to the average values for the Province of Lecce, and a much stronger trend related to the presence of resident population with foreign nationality (Fig. 12b).
If we consider the local real estate market, coastal family houses embody a residual share of bought and sold stock. Today, in Salento, the demand expressed by quality tourism and the related private investments are directed towards other types of settlements, such as historic villages in the hinterland or coastal centres that can offer services and cultural attractions. The settlements in question fail to meet such demand, basically because 'the houses are ugly, and the landscape is disfigured. 9 The quality of construction is poor, the buildings are deteriorating, there is enduring uncertainty over the compliance measures of unauthorised structures, but above all the environment is of low quality, lacking public space, services, and infrastructure. The commercial value of family houses is difficult to estimate, but certainly low, between 500 and 700 €/m 2 average (OMI 2019; Immobiliare 2019).
Within this general downward trend, family houses at Marine seem to encounter two forms of residual demand. On the one hand demand comes from middleclass families with children, residing in the neighbouring municipalities of the hinterland, who can 'spend little and achieve the dream of having a house by the sea' . On the other, the market confirms a growing phenomenon of stable residency, which concerns the elderly, foreigners, and in general low-income families: 'in Lecce houses Fig. 8 a Central Veneto, 10 × 10 km sample. Percentage of one-and two-interior buildings built in the period 1961-1991 out of the total residential stock at 2011 (authors' calculations on data from Istat census). b Central Veneto: trends in the elderly and foreign population within the census blocks where family houses constitute more than 50% of the housing stock (authors' calculations on data from Istat census) are too expensive, but here they are cheap, so I can settle down in a summerhouse and commute to the city in a few minutes. 10

Discussion and conclusions
What provisional considerations can be made on the basis of the general framework and the four outlined portraits? How can these representations contribute to a reflection on public policies, and in particular to urban planning and the management of built environment? Which transformation scenarios emerge in the analysed territories?
The history of diffuse urbanisation in Italy must be considered along with the recent evolution of the family house. It is part of a transformation process that involves large parts of the territory and European society. The overall model of living is changing, albeit with unique features and evolutionary trajectories in each of the various European countries. The aging of the population and changes to the family structure, redefinition of labour and professional markets and their effects in terms of mobility, weakening of the cultural and social ties that have traditionally linked families and places, and the emergence of new generational ideas are a natural phenomenon that affects the fragility of the family house in different European regions (Berndgen-Kaiser et al. 2014;Bervoets and Van de Weider 2015;Gentili and Hoekstra 2019).
Against this background, the investigations allow us to highlight two different conditions.
In Lombardy and Veneto, the economic value of the housing stock has dropped, but it still maintains a significant place in the real estate market. This includes in part older houses that are poorly equipped, sometimes in slightly marginal locations, but in sufficiently dynamic territorial settings. This 'soft' downgrading seems meet the demand that is still present. Such houses are less expensive than other newer and better-performing ones and are an accessible solution for an average family to raise their children or stay close to their elderly parents.
In Le Marche and Puglia, where there is more marked impoverishment, the situation is more critical. Where the family house has been used for production or uses in sectors which are declining, such as tourism and recreation, its fate is less certain. The disappearance of production activities traditionally carried out in a workshop or the move to specialised and better located buildings or areas, as well as the disruptive effects on the landscape wrought by uncontrolled coastal development profoundly affect the residual value of buildings often constructed with modest investments. Dragged into this vicious circle where building quality and environmental conditions mutually influence each other, the family house could lead to more widespread deterioration and become a problematic asset, due to the fact that significant portions of the middle-class have invested their savings in a housing stock which is now becoming economically fragile.
This aspect of the recent history of our country is little represented. The focus of public policies on other territories, firstly on the more dynamic cities and metropolitan areas, and secondly on peripheral areas with critical shrinkage dynamics and fragility, has left a considerable part of the 'intermediate' Italy in the shadows. This part is subject to growing social unease, as regards life projects and expectations that gradually fade from one generation to the next, but also investments and family assets that devaluate, and may bring out behaviours of social and political claim (Lanzani and Zanfi 2018;Ardeni 2020;Mariotti and Di Matteo 2020). Knowing that it will be hard to direct their development, adequate representation of these parts of the country becomes essential.
Within this perspective, recognising the points of resilience and fragility in this housing heritage can be useful for more conscious planning and public action strategies (Secchi 2010).
Where the family house is in sufficiently dynamic location, and where its real estate value has not disappeared, there are various prospects for enhancement, adaptation, and reuse that would allow for continued use. Tax incentives, procedural simplifications, reduction of some municipal taxes, and moderate volumetric premiums could be among the tools to be put in place. This could lead to reliance on the traditional flexibility of the individual house to allow its redevelopment, or imagining shared infrastructural and energy infrastructure to consolidate aggregations that still have a certain sense of identity, or strengthening and densification of settlements using volumetric transfers, including the transferring of poorly placed houses in an advanced state decline (cases which we began to explore in Merlini and Zanfi, 2014).
Scenarios where value is about to drop substantially or is irremediably diminished is different, especially in relation to real estate market trends. Policies based on tax incentives (for housing renovation and energetic performance improvement) of the last 20 years are destined to remain ineffective, as in many cases there is no longer a real estate market capable of remunerating the investments. Two conditions may then arise. On the one hand, impoverished family houses that retain a specific usage value could continue to meet needs that arise in the generational shift or, possibly, in the low-cost housing market. Some policies already act in this way, and show how it is possible to connect the owners of low-value houses with potential low-income renters, at the same time guaranteeing a safe rent regime and a minimum level of spatial quality, while favouring the activation of selfrecovery practices for assets that are convenient for both parties (Lanzani and Zanfi 2017;Laino and Zanfi 2017).
On the other hand, more extreme cases may emerge. Maintenance costs of technological networks and services for public administrations that are in a budget crisis are added to the irreversible loss of value of assets. The most problematic coastal family houses, those in conditions of hydrogeological risk or which are incongruously part of otherwise valuable landscapes, or simply Fig. 10 a Marche, valley of the river Chienti, 10 × 10 km sample. Percentage of one-and two-interior buildings built in the period 1961-1991 out of the total residential stock at 2011 (authors' calculations on data from Istat census). b Marche, valley of river Chienti: trends in the elderly and foreign population within the census blocks where family houses constitute more than 50% of the housing stock (authors' calculations on data from Istat census) abandoned because they have lost too much value, may need to be earmarked for demolition. Widespread demolition will have to be part of urban planning and territorial policies in the near future (Merlini 2019). In our view, in some cases, the family house will be part of it.

Methods
Research presented in paragraph 3 was conducted from January to July 2019, based on the most recent census data and real-estate information available (Istat 2011;OMI, 2019;Immobiliare 2019). Since no specific data are available on the characteristics of the population residing in 'family homes' , data relating to some sociodemographic variables were extracted and analysed for the census blocks in which the concentration of family houses was greater than or equal to 50% of the housing stock. The trajectories of change of the population residing in this type of housing were then reconstructed and mapped. As regards time series analyses, the 1991 and 2001 census values were attributed to the geometry of the 2011 census blocks, using a method based on the centroid position of the 1991 and 2001 census sections, compared to those of 2011. Moreover, for the real estate market analysis, the databases accessed contained the minimum and maximum real estate values for sale and rental, according to the type and state of conservation of the building (in our case, the ville e villini-villas and cottages-type was selected).
Finally, between June and July 2019, we conducted four in-depth semi-structured interviews with real estate brokers who were regional experts. Interviews revolved around four main topics: the share of sold properties that were family houses; the characteristics and locations of the buildings; the profiles of those who buy and sell; and the prospects of the real estate market related to family house type. on urban and social transformations through data analysis and mapping.
Fabio Manfredini holds a Master of Science in Environmental Sciences. He is responsible for the Mapping and Urban Data Lab at the Department of Architecture and Urban Studies, Politecnico di Milano. His main areas of expertise are methods of territorial and environmental analysis, statistical and spatial analysis, mapping and data visualization. Fig. 12 a Municipality of Lecce, 10 × 10 km sample. Percentage of one-and two-interior buildings built in the period 1961-1991 out of the total residential stock at 2011 (authors' calculations on data from Istat census). b Municipality of Lecce: trends in the elderly and foreign population within the census blocks where family houses constitute more than 50% of the housing stock (authors' calculations on data from Istat census)