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Dense environments have always carried dual connotations – on one side they are considered positive due to the sustainable use of resources and the intense social links they generate, but on the other side they are recognized to generate negative effects on humans, such as stress. Starting with the industrial revolution, a strong debate arose regarding the benefits and downsides of density, especially regarding the relation between existing crowded urban environments and the programmatic development of new healthy environments. The debate remained unsolved for a long time, until recent studies have determined an important element that actually shifts the balance between good or bad density, namely the quality of an environment.

I’m currently reading cities full of space, qualities of density by Rudy Uytenhaak. He argues that the built density is the source of a loss of (natural) quality, and the role of urban and architectural design is that of neutralizing this effect by eliminating oppressive spatial configurations and by generating diversity through the design of “intelligent puzzles”.

rudy uytehhaak-desaturatedRudy Uytenhaak Architectenbureau

The quality of density is the most significant feature of the urban built context, and as Uytehnhaak R. points out, “without sufficient quality, density does not work – it even becomes dangerous”. This idea balances the previous interdisciplinary discussions about the justifications underlying positive or negative high-density architecture models of the architectural culture, determining the defining criterion for models with a correct functioning. Spatial quality, as he states, should be sought for in the architectural design of new buildings as a way of compensating for density and its potential negative effects.

Dietmar Eberle (Baumschlager Eberle), in a lecture held at TU Graz on Density, talks about density as determining the urban atmosphere, and that this atmosphere is mostly dependent on the character of the empty public space. The empty open space is what makes us relate to a place. After studying 4 different cities and 40 different locations within those cities, he concludes that the quality of density isn’t good or bad, but it simply has automatic fixed determinations upon quality, atmosphere, people  fluctuation etc. Also, the categories of density represent the current values of time and society. Currently, the quality of a neighborhood is proportionally related to the quantity of public owned open space – 30%…40% for qualitative neighborhoods. So, open space must be increased in order to obtain quality in dense environments. Buildings and open space remain un-ordered in built densities under 1,5, meaning that the position of buildings remains insignificant to other buildings and their organization is based on other characteristics of the interstitial spaces. With densities higher than 1,5, the open space and buildings start to become ordered in relation to the other buildings. higher density attracts also an increase in visual richness (important in relation to quality),in the careful care of public space, the walk-ability and the mixed-use quality of a neighborhood.

In relation to dense residential environments, I am also interested in the study of collective housing typologies.

Collective or mass housing is defined primarily by quantity and it acquires its spatial quality through grouping. This type of dwelling houses large numbers of people with varying degrees of housing quality. Within it the housing units are closely grouped, according to rules of horizontal or vertical assemblage, generating spaces with public, semi-public or private character in which certain social practices of housing unfold. Collective housing draws its name origin from the way in which the building is accessed, namely by a common path serving all the units [1].
In an attempted typological classification of contemporary collective housing models of high-density, I turned towards a non-exhaustive generic formal classification, based on the studies of Mozas J and Per AF from the “Density Series” books [2]. Each of the typologies uses as starting point the individual housing unit, the apartment, which is consequently multiplied in an identical or variable pattern of configuration. The typological categories vary according to composition principles based on the housing unit, on size and by the way in which the building relates to the urban tissue.

Houses

Starting from the singular and abstract typological unit represented by the individual house, the first category is driven by multiplying, joining or overlapping multiple units. The configurations generated by those operations are either classical attached or row houses, either contemporary types of folded row or stacked houses.
The individual unit is usually related to the terrain, benefiting of a court or a terrace and of direct individual or paired access from the ground level. This category makes the transition from individual housing to collective housing of a higher degree of density.

1 HOUSES

Blocks

The second typology represents a quantitative increase in size, in number of individual units and scale compared to the “house” typology. The block height is moderate, usually ranging between 3 and 5 levels; this height is traditionally justified by the number of levels convenient for walking. Its relative low configuration, its flexible footprint on the ground and its scale allow the object to enroll organically within the context.
The block can be freestanding on the plot, it can have free sides or it can continue an existing building by cleaving onto a party wall.

2 BLOCKS

City Blocks

The city block  is an urban building flanked on all sides by streets in relation to the urban fabric. Its scale is directly related to the scale of the city. The city block generally involves a large spatial diversity and a relatively high privacy degree. It can have the same height as the block typology or higher, depending on the context. Buildings ranging between 4 to 7 levels are ideal in terms of energy footprint, which is lower than that of taller buildings.

3 CITY BLOCKS

High-Rise Buildings

The high-rise type, also known as tower block, is represented by tall buildings with multiple levels. There is no universal definition for the number of levels that determines a building to gain this status; this height is variable according to different geographic areas.
This typology is justified by economic considerations, not only in relation to construction costs, but also in relation to urban infrastructure and land resources. Their impact on the neighboring urban tissue is high and the main disadvantages are excessive shading and energy consumption.
The stacked units block is the most interesting type from my point of view, being able to generate spatial quality and diversity. It derives from additive processes of small scale units or overlapped uneven floors.

4_2 HIGH RISE

Mixed Solutions

The mixed solution typology involves combinations of the above, justified by context and project brief. There are no precise formal categories for this typology.

References:

[1]   Zahariade AM. Arhitectură Locuire Oraș, ALO 2009-10. Second year’s course, second semester. Department of Hystory & Theory of Architecture, Faculty of Architecture, UAUIM, Bucharest.

[2]   Mozas J, Per AF. Density: New Collective Housing. A+t ediciones, Vitoria-Gasteiz; pp. 14-17, 2004.

Population density is a phenomenon related to the way in which the population is distributed on the land surface. The population is unevenly distributed across the land, reaching high concentrations in large urban areas while large areas of land remain uninhabited, because people naturally tend to concentrate in areas with desirable conditions, like those of urban areas. The differences in population distribution are high both across countries and between regions of the same country [1], and thus the concept of density of the built environment has relative connotations when trying to compare indices of different areas.

Starting from this fact, it becomes clear that the exact definition of the term high-density architecture can be difficult. The term “density” is itself a complex concept, involving some diversity in terms, and defining it is important before beginning a discussion on density in relation to architecture.

The Definition of Density

High density refers either to physical density, namely the density of a large number of people or the built density related to the land surface, either to subjectively perceived density in relation to the environment and to other participants into a certain space. Physical density is a numeric measure of the concentration of individuals or of physical structures in a certain geographic unit, being a spatial objective indicator, quantitative and neutral. In practice, it only makes sense when linked with a specific reference scale. On the other hand, perceived density represents the individual perception of an estimated number of people present in a given area, of the vacant space and its organization. The character of space itself is important for the perception of density, but the interaction between individuals and environment as a whole is more important. Also the individual cognitive attributes and socio-cultural norms are factors that contribute to this interaction. Perceived density doesn’t only refer to the relative relations between individual and space, but also to the relations between individuals located in the same space.

The definition of density in relation to built environment can have different meanings or different quantification according to the method of analysis and spatial indices taken into account. There is no universal standard formula, only some of the formulas are being used more as opposed to others. Usually, in architecture and town planning, two categories of measurement are used for physical density: population density (Fig. 1) and building density (Fig. 2). Population density is defined as the number of individuals or households per given area, and the building density is defined as the ratio of building structures related to plot surface. All those measures are used in urban planning policies.

population density
Figure 1. Population density

built density
Figure 2. Building density

Building density has a complex relation to urban morphology, playing an important role in determining the urban form. Different combinations between the plot ratio and site coverage will manifest into a variety of different built forms, and urban development of the same density can take very different urban forms [2].

The differences between the surface distribution of population density and that of building density are visible when comparing data of almost every urban tissue. The following example illustrates the difference between the two densities in the case of Timișoara, by graphically expressing the data for the year 2011.

Z:1_PROIECTE63_pug4_work1_urbanism1_ETAPA ANALIZA2_PRED

Figure 3. The difference between the distribution of densities of people and buildings in Timișoara.

Source: illustration from the board Development Analysis I 13_Densities, General Urban Plan (PUG) of Timișoara, drawn by Vitamin Architects based on data provided by the City Hall of Timișoara and used with the consent of Vitamin Architects [3].

In reality, especially when the geographic reference unit is one at large scale, the distribution pattern of people or buildings can vary significantly. To solve the spatial variation of density, different measures have been introduced, such as density gradient or density profile. The density gradient is a composite measure of density and is defined as the rate in which density decreases in relation to the distance towards a reference location, usually calculated according to concentric circles (Fig. 4). By comparing the patterns of density over a period of time, the process of spatial evolution of the city can be depicted, showing either decentralization with a drop of population density in the center and increased density towards the outskirts, either centralization with a growth in population density in both center and outskirts, and the expansion of the borders (Fig. 5) [2].

gradient densitate ENG

Figure 4. Population density gradient for an abstract case.
Figure 5. Density gradients over time: (a) progressive decentralization; (b) centralization.
Source: Illustrations adapted and redrawn after Vicky Cheng (2009, p. 8).

From the perspective of rapid urbanization, the relationship between urban density and built form has always been an important focus of research, determining massive mathematical and geometrical investigation upon the spatial benefits of buildings with multiple levels. The presented definitions and measurements of density are the most relevant ones in relation with the subject of density from an architectural point of view, but they are not the only ones.

References:

[1]   Freedman, JL. Crowding and Behavior. San Francisco: W. H. Freeman and Company, 1975.

[2]   Cheng V. Understanding Density and High Density. In: Ng, Edward (Ed.). Designing High-Density Cities For Social & Environmental Sustainability. London: Routledge; pp. 3-17, 2009.

[3]   Public document downloaded from the City Hall of Timisoara web-site: http://www.primariatm.ro/uploads/files/PUG/URBANISM/parte%20desenata/03_ANALIZA%20DEZVOLTARE/13_ad_DENSITATI.pdf.

I started this blog quite abruptly, and missed out on a proper introduction, but not unintentionally. I  focused more on the concept of density and its meaning, and I’m still pondering things. So, this would be a kind of delayed introduction…

what about density 2

The continuous growth of population in relation to a constant earth surface and to the limited or hardly renewable resources is one of the global concerns. The year 2006 represented a key moment in the evolution of the phenomenon, because from this point on the inhabitants of the cities exceeded half of the world’s global population. It is estimated that in the near future the population, and particularly urban population, will continue to grow, at such a rate that two out of three people born in the following thirty years will live in cities [1]. The population growth requires a physical and spatial support and directly attracts the demand for housing. In this context high-density architectural forms and dense urban environments represent the most viable models for the future in general and for housing in particular.

The implications of high-density architectural models in the current moment overpass the realm of the architectural object and acquire social, ecological and urban meanings. The connotations of contemporary density and the relations they have with the city are important for understanding the way in which high-density architectural forms return to the international culture after a period in which they have been perceived and discussed as a negative phenomenon [2].

The forms of dense architecture have dual connotations, both positive and negative, and the balance between the two is a fine one, based in part on scientific evidence and partly on subjective perceptions. On the one hand, design that uses principles of high-density is more compact and manages to conserve important land resources, reduces required distances for transportation and therefore the energy use, and represents a more economically efficient model. There is also the assumption that areas containing high numbers of people are themselves sources of variation, of intensity and diversity, and that densely populated areas provide a communication experience with multiple possibilities and therefore a very rich exchange of ideas [3]. On the other hand there are potential negative implications directly linked to increased noise or lack of intimacy, or more subtle implications, supported by a number of sociological and behavioral studies that identify crowding as a source of stress and as a factor that can cause behavioral changes in people, in conjunction with the architectural environment [4]. Recent researches in neuroscience come to support sociological speculations about the implications of crowding on stress, recently discovering that people born in large cities and involved in a larger social network have an increased amygdala compared to other people (amygdala being a region of the brain associated with memory and emotional intelligence) [5].

what about density 1

I will try to focus my future study on dense architectural forms in relation to housing, because housing is one of the most inciting themes of architecture, by its universal character and its relation to one of the most basic human needs, that of dwelling. Additionally, the forms of housing are the result of multiple overlapping contexts, namely political, social, cultural, geographical and beyond. High-density collective housing is being reconsidered as a viable design solution in the current context, but although life planning, social rituals and economic conditions are constantly changing the architectural support remains yet stable. Currently, collective housing is an architecture program in which innovation is not actually perceived, compared to the museum program for example, and the principles of spatial and planimetric configuration remain the traditional ones. The rooms and the functional relations between them remain those intended for a traditional family in relation to a society in which the classical family tends to disappear, being replaced by other dynamic social structures defined by complex relationships [6]. The justification of that is partly linked to the commercial interests of the construction industry seeking maximal results with minimal risks and investment, and partly to the conservative mentality of the population in relation to housing.

Taking into consideration the implications of the recent economic crisis, most of the major current crisis are based on real estate crisis. A large number of families have recently lost their homes which they bought by credits that they couldn’t really afford, aiming for an ideal home and ignoring their real possibilities of purchase. The number of those that can afford an individual home on a plot with a garden is continually decreasing, and the environmental implications of individual houses are negative, respectively a high consumption of energy for transportation, an increase in the number of private cars and pollution generated by burning fossil fuels. However, this dream seems to have been the only available alternative until now for a family in relation to the available housing typologies [7].

It is obvious that traditional design methods are no longer viable under current conditions, and finding new ways to design high-density built environments is a necessity. These new concepts should achieve a balance between the dream of a rural house and the reality and necessity of living in dense urban areas, combined with the real economic possibilities.

what about density 3

References

[1]   By the Editors. Street-Savvy: Meeting the biggest challenges starts with the city. Scientific American, Volume 305; pp. 38-41, 2011.

[2]   Clemente MC. High-Density Collective Housing and Urban Space. In: Segatini MA. Contemporary Housing. Milano, Skira editore, pp. 17-23, 2008.

[3]   Schumacher P. My kind of town, http://www.architecturetoday.co.uk/?p=22997. Accessed in 21.05.2012.

[4]   Baum A, Vallins S. Architecture and Social Behavior: Psychological studies of social density. New York: John Wiley & Sons Inc, 1978.

[5]   Katsnelson A. The Stress of Crowds. Scientifica American, Volume 305; pp. 38-41, 2011.

[6]   Schittich C. The Challenge of High-Density Housing. In: Schittich, Christian (Ed). High-Density Housing: Concepts Planning Construction, In Detail. Műnchen, Birkhäuser Architecture, pp. 8-11, 2000.

[7]   Maak N. Japanische Architektur als Vorbild Der Fluch des Eigenheims. Frankfurter Allgemeine, Feuilleton, 04.01.2012.