The Bartlett School of Planning


Sonia Freire Trigo

Research subject

Primary supervisor: Dr. Claudio de Magalhães
Secondary supervisor: Dr. Ben Clifford
Thesis title: Vacant Urban Land: Production Process in an English Context.

Starting date: 27th September 2012

Projected completion date: December 2015

Regeneration of Vacant urban land in England.

Urban regeneration policies in England have been driven by a property-led approach for a long time. Accordingly, vacant urban land has been usually addressed from a neoclassic economics point of view. Therefore, most of the attention has been drawn to the development process of land and the barriers or constraints to bringing vacant land back to ‘beneficial use’. Despite the efforts, there are some ‘hopeless sites’ that seem to have fallen out completely of the re-development process. These long term vacant sites are doomed to remain vacant for even longer due to the current economic crisis, unless they are addressed from a different point of view. The present research will try to provide this new approach and poses the following questions:

1. What is the production process of vacant urban land?

2. How does this production process affect the re-use of that land?

Accordingly, the working hypotheses of the research are the following:

The production process of vacant urban land is a conceptual and physical process determined by the interactions between the different agents and institutions involved in it.

The extent to which these interactions narrow down or open up the possibilities for different perceptions of the (exchange/use) value of land to happen, determines the vacancy period of land.

In order to test these hypotheses, the research will use a case study approach. The selected cases – long term vacant sites in London – will be explored through documentary research and semi structured interviews.

Ultimately, the research will try to prove that the problem of vacant urban land though physical in its appearance has an intangible dimension to it, which has to do with the management of different perceptions of the value of land.


My career started as an urban planner after I got my BArch and MArch degrees at Coruña University (UDC - Spain). I worked five years for the private sector delivering a range of urban projects, from medium size master plans to street refurbishments, being involved in both their design and management processes.

Due to my previous experience, I became interested in the interactions between the urban and regional scales of planning and decided to take an MSc degree in Regional and Urban Planning at Madrid University (UPM - Spain). During that period, I took part in two research projects: the delivery of a best practice catalogue of urban agriculture experiences across Spain, for Vitoria’s city council; and the assessment of the sustainability of Madrid’s social housing existing stock, with Professor Luis Moya.

I joined the Bartlett School of Planning in 2012. Since then, I have been a Postgraduate Teacher Assistant for Professor Matthew Carmona’s MSc Urban Design: Place Making and for Dr. Jessica Ferm’s Urban Project Managementmodule. In  addition, I have recently finished a research project with Professor Mike Raco (UCL) and Dr. Emma Street (University of Reading) and will shortly begin another research project with Dr. Claudio de Magalhães (UCL), funded by RICS Research Trust

Finally, I have been recently appointed Treasurer of the RGS-IBG Planning and Environment Research Group (PERG)

Publications and other work

Publications and other work


November, 2012Understanding Madrid’s Peripheral Vacant Land. A means to a physical regeneration in EURAU12 Porto | Espaço Público e Cidade Contemporânea. ISBÑ 978-989-8527-01-1; Faculdade de Arquitectura da Universidade do Porto, FAUP. O Porto.

November, 2011Los vacíos urbanos. Causas de su existencia en el suelo urbano de la primera periferia de Madrid in Territorios en Formación, Nº1, Biblioteca Universitaria, UPM. ISSN-e: 2174-8659. 

July, 2011: Los vacíos urbanos. Factores endógenos implícitos en su existencia dentro del suelo urbano consolidado in DUOT (UPC). ISBN: 978-84-615-1968-2.

December, 2010Energy and equity. Reflections on an Ivan Illich’s text in Biblioteca CF+S, Nº 46, Instituto Juan de Herrera. ISSN: 1578-097X 

December, 2010Torre Negra’s Rural Park (Sant Cugat del Vallés). The unbearable heaviness of planning and its effects in CF+S Library (ISBN pending) 

December, 2010Sabadell’s Agricultural Park. Urban growth constraint by means of a public realm recovery for citizens in CF+S Library (ISBN pending)

Research Projects

2014: Data analysis and interviews for a research on The Private Management of the Urban Public Realm, funded by RICS Research Trust, with Dr. Claudio de Magalhães (UCL)

April 2013 / September 2013: Data analysis and interviews for a research project on the Transformation of Community Consultation in Local Development, with Professor Mike Raco, UCL and Dr. Emma Street, University of Reading.

2009/2010: Data analysis and publication of a 2 online papers about Peri-urban agriculture in Sant Cugat del Vallés and Sabadell, with Initiative for a more Sustainable Architecture and Planning Research Group (GIAUS).

2009/2010: Analysis of social housing sustainable features on the outer neighbourhoods of Madrid, with Social Housing, Basic Habitability and Urban Heritage Research Group. UPM.