IJPDS International Journal of Population Data Science

The London Borough of Islington has successfully developed indices of overcrowding, providing a more accurate picture of housing conditions in the area. This project, led by researchers from University College London and Islington Council, sought to address the limitations of national data and offer granular insights on residents’ housing conditions to inform local policy.

The study, conducted in Islington, merged data from various sources, including Energy Performance Certificates (EPCs), council tax bands, council housing databases, and several other data sources on people and property from the council, using the Unique Property Reference Number (UPRN). This comprehensive approach allowed the team to generate two indices of overcrowding for households with dependent children, based on the numbers of bedrooms and the amount of space in the home.

Despite encountering challenges such as missing data and ambiguous definitions of overcrowding, the researchers demonstrated the feasibility of creating useful overcrowding indices. They highlighted the need for clearer definitions of bedrooms and better access to national records to improve local estimates.

The findings reveal that locally-derived overcrowding prevalence was higher than national estimates, underscoring the importance of tailored local data in addressing housing issues. The project also emphasises the value of real-world data sources for local population research and policy development.

Funded by the National Institute for Health and Care Research (NIHR), the study, published in the International Journal of Population Data Science (IJPDS), provides valuable recommendations for other areas seeking to generate their own overcrowding indices. The researchers call for improved data sharing between housing providers and national agencies to support local councils in developing effective strategies to support resident wellbeing associated with housing conditions including household overcrowding.

Laura Scott, lead author and Principal Data Specialist from Islington Council said, "The results of this analysis will allow us to better target our resources at those who need them most, and a range of projects have already been implemented with the aim of helping our families struggling with the effects of overcrowding".

As the housing crisis continues to impact communities across the UK, this innovative approach offers a promising solution to better understand and address the challenges of overcrowding, ultimately improving the wellbeing of affected families.

 

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Laura Scott, Principal Data Specialist, London Borough of Islington, UK

Sheringham, J., Weigang, Y., Ucci, M. and Sheringham, J. (2025) “Data Note: Challenges when combining housing data from multiple sources to identify overcrowded households”, International Journal of Population Data Science, 8(5). doi: 10.23889/ijpds.v8i5.2927.