The quality of life a city affords its residents is generally determined by the relationship between density and amenity. Urban density refers to the number of people inhabiting an urbanised area and is therefore based on housing. Although there are significant variations in this ratio across cultures, density is generally used as a determining factor in assessing urban living conditions and planning the future growth of cities.

While denser, more compact cities align with the imperative to create more sustainable urban environments, where demand on limited natural resources is reduced, the qualitative implications of urban density must also be considered.

The following is a series of not necessarily related thoughts on the management of urban density:

1. The character and quality of the European city is the result of a myriad actions by many over many centuries. The foundations of a city stem from a favourable geographical situation, but the numerous ways in which growth occurs are the result of a complex set of circumstances that may become more difficult to decipher over time.

24.01.2019, London, UK

26.01.2019, Zurich, CH

1. Cities should be considered part of our heritage, a form of cultural inheritance that includes both tangible and intangible elements: places, customs and beliefs that are significant for the articulation of space and the built environment, and affect the lives of residents. The views of inhabitants about the need to preserve buildings that are deemed of cultural value tend to change over time. Conservation is a contemporary phenomenon legally based in planning regulations, but this does not adequately explain why large parts of many cities have survived over centuries. Buildings whose retention may hinder the need for densification or development are always vulnerable to demolition.

31.01.2019, Hong Kong, HK

02.02.2019, Zurich, CH

1. More buildings have been completed in the last 50 years than in the whole of the preceding history of architecture. Much of this has taken place in developing nations, and an unprecedented transformation has occurred in many European cities. While their core urban structure tends to resist change, their character and identity has been impacted by the pressure to grow.

17.02.2019, Zurich, CH

27.02.2019, Zurich, CH

1. Normative building programmes are the biggest component of any city, and housing accounts for the most significant proportion. Typically, 70 percent of a city consists of residential buildings with their own morphological and typological characteristics.

10.03.2019, Lugano, CH

27.03.2019, Zurich, CH

1. European cities with a strong industrial and manufacturing past which is now in decline have the potential for large-scale transformation. Former industrial buildings are sometimes converted to serve residential or ‘white-collar’ work uses. In some instances, this transformation is preceded by the colonisation of former industrial buildings by creative communities, although this is often shortlived. Once such communities become established they tend to be displaced by the increase in property values their presence drives. In other situations, substantial former industrial areas have been cleared and after an expensive decontamination process, whole new neighbourhoods are developed to considerably higher levels of density than existed before.

22.04.2019, Basel, CH

23.04.2019, Zurich, CH

1. Density can be measured and quantified. The way it is measured differs from one country to another, and affects the way cities are built. For example, in the UK density is referred to in terms of habitable rooms per hectare, whereas in continental Europe it is measured more precisely in terms of useable building area. This difference in approach partly explains the British tendency to build to a lower level of density – at least until recent times.

13.05.2019, Zurich, CH

17.05.2019, Lugano, CH

1. Measuring density does not account for the character of a city and the myriad atmospheres it contains. As visitors, we are acutely aware of the density of different city neighbourhoods, but it is the character and quality of buildings that create a lasting impression.

18.05.2019, Canton Uri, CH

23.05.2019, Zurich, CH

1. The largest proportion of a city is formed by what we refer to as suburbia. While this is generally perceived in somewhat negative terms, the area it covers and the population it houses is considerably greater than the city centre. The peripheries of cities are generally built to a lower level of density and have the greatest capacity for densification because they tend not to include protected, culturally significant buildings.

06.06.2019, Zurich, CH

09.06.2019, Zurich, CH

1. In expanding European cities there is generally a discrepancy between supply and demand. Cities are rarely capable of responding quicky to the need to provide large numbers of additional homes when the population increases rapidly. While in the long term a balance may be achieved, any shortfall allows speculative house builders and developers to profit. In London, this discrepancy has led to an increase in property values that is globally regarded as one of the best forms of short-term financial investment. Whole areas of Central London have been bought by foreign investors who have no interest in occupying homes, other than enjoying the increased value they will command in future. This has created a dysfunctional city where key workers cannot afford to live and need to travel ever greater distances to find affordable accommodation, while the centre lies empty.

12.06.2019, Canton Ticino, CH

21.06.2019, Geneva, CH

1. We tend to think that a city’s urban fabric needs to become denser. This is not universally applicable. There are numerous European cities, often those formally associated with industrial production or with the movement of goods, which are economically stagnant or in decline. The experience of visiting formerly densely populated neighbourhoods where depopulation has occurred is a depressing and unsettling spectacle, but it is interesting to witness how quickly nature contributes to the decay of unmaintained buildings. If managed carefully, depopulation and reduced density could be an opportunity for a city. The difficulty is that cities do not generally have the financial means to profit from such opportunities.

24.06.2019, Meyrin, CH

29.06.2019, Brussells, BE

1. As contributors to the reshaping of the European city we acknowledge the great responsibility the task demands. We feel that ensuring the future life of cities requires a process of densification to absorb demographic growth and accommodate changing urban living patterns.

30.07.2019, Stockholm, SE

30.08.2019, Mendrisio, CH

1. Before the end of the nineteenth century, densification was achieved by building in an ever more compact manner. The distance between buildings was reduced, but the height of residential buildings never exceeded what was deemed a reasonable height to be climbed up a staircase. The lift or elevator changed this simple state of affairs. Today, the ‘reasonable’ distance between one block and another results in fragmentation and distancing, rather than fostering neighbourliness. The lift allows buildings to reach ever higher above the street, which distances residents from the life of the city. Paradoxically, the time spent in a lift offers a rare moment of encounter with other residents of a building. Generally, the older, historical parts of European cities have a much more pleasant atmosphere and social life because of their dense, low-rise urban fabric.

05.10.2019, Mendrisio, CH

31.10.2019, Lugano, CH

1. Today, for the first time in history, the number of urban dwellers is greater than that of people living in rural areas across the globe. This turning point was reached at the start of the twenty-first century, and everything points towards the trend continuing. In Europe the balance between town to country dwelling has seen the dominance of the former since the moment industrial production overtook agricultural work. Considerably more land is still devoted to agricultural production, forestry or nature conservation, as is evident on flights across Europe. While we may question the efficiency of localised agricultural production systems, the structure farming brings to the land and open landscapes is regarded by many as a form of national heritage to be treated with respect and pride. Others feel more ambivalent.

05.11.2019, Zurich, CH

09.11.2019, Rome, IT

1. It is widely recognised that it is better to consolidate existing cities and limit their outward expansion rather than allow ever greater greenfield areas of land to be consumed by building. Planning agencies in many European cities enact this as planning policy and limit development through statute, building law and well-defined political processes. This inevitably leads to a process of densification and the creation of more compact urban forms.

27.11.2019, Helsinki, FI

01.12.2019, Zurich, CH