My last post, which was dedicated to densification in Lausanne, provoked a courteous and detailed response from the President of Lausanne's Socialist Party, Benoît Gaillard. His remarks raise interesting questions about densification and its local implementation. The following thoughts are based on the examples of Vaud and Lausanne, but they are applicable everywhere.

Firstly, it is necessary to agree on what we mean by the concept of urban densification. Essentially, it is a movement that appeared as a reaction to urban sprawl and the building of suburbs consuming large amounts of energy and surface area. It therefore argues that demographic growth should be concentrated in already-built areas through increasing the density of these spaces rather than opening new areas to construction.

Translated into figures, densification implies that the growth of cities, downtown areas, and regions already built upon should be greater, or at least as great, as that of urban fringes, outskirts, and regions without buildings. For the Canton of Vaud, the policy of densification ought to translate into greater portions of both housing construction and population in the city than elsewhere. It is by this standard alone that the success or failure of the policy of densification should be measured.

With this clarification, let us return to the numbers. As we know, for the past decade or so the country has been experiencing vigorous economic and demographic growth, especially in the Canton of Vaud. Between 2001 and 2012, Vaud gained 114,000 residents. The average household size in the canton being 2.2 people per household and assuming one household corresponds to one housing unit, this increase in population translates into about 52,000 new homes needed. Contrary to common belief, construction corresponded to growth rather well since 41,500 new homes were built in the canton during this period. It is insufficient, but rather high, meeting 80% of housing needs.

It is another story in Lausanne. In 2012, the city included 17.8% of Vaud's population. In order to respond to the objectives of densification, it would have been necessary to construct a similar proportion of homes as in the Canton, or about 8,300 homes. Taking into account that urban households are on average smaller than elsewhere (1.9 people per household in Lausanne, 2.2 in the Canton), this figure becomes 9,300. In reality, only 3,600 were built. That amounts to less than 40% of the demand, and this shortcoming represents more than half of the canton's deficit. Lausanne has expressed fear about doing too much, but in relation to the goals of densification the problem is not doing enough. Through fearing the rejection of densification, densification is simply not happening.

Consequence: some circles laud the "return to the city" and population statistics that show that the overall proportion of Lausanne's population in the entire canton continues to decline. In 1960, 30% of Vaud residents lived in Lausanne. This figure is now at its lowest in a century at 17.8% and continues to decline. Of the canton's 114,000 new residents since 2001, 100,000 settled outside of Lausanne. The numbers show that year after year, decentralization is occurring.

So, what must be done if we really hold to the objective of urban densification as advocated by those on the left for the past quarter century? We can start by clearly responding "yes" to the question of whether or not it is right to replace a building with 4 homes with one having twenty four, even if exceptions are clearly possible. Especially since it is not possible to do just anything: for forty years our cities have been protected from reckless development by restrictive rules designating surfaces for building, land use, and the number of lots on each parcel.

Our neighborhoods are sheltered from rapid densification. It's worth considering that in one part of Lausanne, at least 9 repossessed buildings were densified, the same number of rental buildings in the area. Looking at it closer, in a neighborhood I know well from living there for ten years, the plot in question is a borderline urban infill – the area's architectural unity calls for densification. Beyond arguing over numbers, the harsh reality is there: if we wanted to be consistent in terms of urban densification, the effort required on the part of cities would be excessive. In Lausanne it would be necessary to build two and a half times more than is currently being built. It is not worse because Lausanne has built in downtown areas. Benoît Gaillard is correct about one point: it is not guaranteed that the population would accept such a program.

The point I made in a previous post remains: when we are confronted with the calculated reality of what following a clear path of densification would mean, we realize that it may only be possible through extreme measures. It would include difficulties such as expelling people and razing buildings: we will not simply achieve it through "soft" densification on free lots without neighbors. So, considering this trade-off, the concept of densification itself should be the subject of debate. Maybe people will at last stop empty talk about the idea without applying it, even if it means to accept that maybe it will never happen.

But we can take comfort. We can live in a world without densification – after all, that is exactly the world we are already living in.

What is necessary to make urban densification successful and liveable for residents?

Original article, originally published in French, can be found here.

Credits: Images and data linked to sources.