To build or not to build, that is the question!

The planning of a city involves the structuring of development models that meet its growth needs in the most sustainable way possible, that is, in an economically, socially and environmentally balanced way.

The basic premise for planning the development and operation of a city is to know, with reasonable precision, if it should grow and by how much. Urban growth forecasting models are tasked with capturing intrinsic and complex relationships in space and time.

Spatial complexity reflects the impact of numerous biophysical and socioeconomic factors. As a result, heterogeneous patterns appear at all locations and scales, making urban development a dynamic and non-linear process, which introduces high levels of hermeticism in temporal assessment. In addition, the process of urban growth is associated with decision-making.

The decisions of urban planners and policymakers are difficult to predict, especially over long periods, as they depend not only on technical demands and solutions, but also on social and institutional pressures from different actors with the most varied types of interests.

However, considering all the difficulties and uncertainties present in the different forecast models, once the most appropriate one for the moment and for the specific city is chosen, with the levels of precision considered acceptable, the results will surely lead to the answer of the need or not to build , especially from a housing point of view. However, if the answer is positive, the next question refers to the place (where) and the way (how to do it).

Obviously, interventions in the city and the way they are carried out can have important side effects. However, in this process, it is also essential to know the effects of non-intervention or wrong intervention.

Bringing this problem to the city of São Paulo, the housing deficit shows us the effects of the lack of construction. However, it is possible to see, daily, the perverse implications of the construction, even if insufficient, in the wrong places.

According to a study by the economic consultancy Econnit, the housing needs of the city of São Paulo until 2030 are divided into two main groups: existing housing deficit and future demand.

The study points out that the restricted housing deficit in the city of São Paulo (2019), which excludes units with excessive rent burden, is 322,660 units. Adding this number to the demand for housing, estimated at 462,681 units, we will need, by 2030, 785,341 housing units.

Consequently, the question that follows is: where will we build these units, and how will this be done?

Where to build means defining the region of the city in which this will be carried out. This implies determining what type of infrastructure and quality of life will be offered to the people who will inhabit these houses. How to do this requires the definition of the way to make technically and economically viable, in the chosen region, the implantation of these dwellings.

The regions of the city with the best infrastructure already know where they are. Economic viability depends primarily on production costs and financing models. The cost of production fundamentally depends on the cost of land, which fluctuates, among other parameters, with the relationship between supply and demand in the market.

We are on the verge of reviewing the Master Plan, so it is time to think about how city planning can help resolve these issues.