Flat Britain: The urban density gap and how to close it – Centre for Cities

Report on Urban Density and Sustainable Development in Great Britain

Executive Summary: Aligning Housing Policy with Sustainable Development Goals

This report assesses the critical need for increased residential density in Great Britain’s cities to address the national housing crisis, enhance economic prosperity, and meet key Sustainable Development Goals (SDGs). Higher-density urban development is identified as an essential strategy for achieving SDG 11 (Sustainable Cities and Communities) by providing adequate and affordable housing (Target 11.1) and fostering inclusive, resilient urban environments. Furthermore, it supports SDG 8 (Decent Work and Economic Growth) by improving the performance of major urban economies and SDG 13 (Climate Action) by enabling more efficient land use and transport systems. The analysis identifies where and how densification should occur to align national development with these global sustainability targets.

Analysis of the Urban Density Deficit

Comparative Findings and the SDG 11 Gap

A comparative analysis reveals a significant “density gap” between British cities and their international counterparts in France and Japan. This deficit represents a substantial challenge to fulfilling SDG 11. Key findings include:

• A Major Housing Shortfall: If British cities matched the density of their French or Japanese peers, their urban cores could accommodate at least 2.3 million additional homes, directly addressing the housing accessibility goals of SDG 11.1.
• Concentration in Major Cities: Over half of this total density gap is concentrated in Britain’s 12 largest cities outside of London, indicating a critical area for targeted intervention to create more sustainable urban centres.

The Widening Gap and Missing Housing Typologies

The analysis indicates that this urban density gap is widening, with slow construction over the last decade contributing significantly to the current shortfall. The primary cause is a lack of mid-rise (3-9 storey) apartment buildings. This “missing middle” housing is crucial for developing compact, energy-efficient cities that reduce urban sprawl and support sustainable transport infrastructure (SDG 11.2), thereby contributing to climate resilience (SDG 13).

Strategic Recommendations for Sustainable Urban Densification

To close the density gap and advance the Sustainable Development Goals, a series of coordinated actions are required.

1. Prioritise Densification in Key Economic Hubs

   Focus development efforts on Manchester, Birmingham, Leeds, and London. Transforming the urban cores of these major cities is fundamental to achieving national progress on SDG 11 (Sustainable Cities) and SDG 8 (Economic Growth).

2. Facilitate Mid-Rise Housing Development

   Policy must make it significantly easier to build mid-rise housing to create more inclusive and sustainable communities.

   • Enable large-scale construction of mid-rise flats across entire urban cores, not just city centres, to provide diverse and affordable housing options (SDG 11.1).
   • Support infill development and increase redevelopment rates in low-density areas to promote efficient land use and reduce pressure on greenfield sites.

3. Accelerate National Planning Reform for Sustainability

   Ambitious reform is needed to create a planning system that actively supports sustainable densification, in line with SDG 11.3 (inclusive and sustainable urbanisation planning).

   • Consider a flexible zoning system to shift the burden of proof towards supporting appropriate densification.
   • Implement bold, pro-density reforms for Brownfield Passports and planning committee rules.
   • Reverse or remove anti-supply measures that hinder the construction of necessary urban housing.

4. Adopt a Holistic Urban Core Strategy

   Mayors and local authorities must broaden their focus to encompass the entire urban core to achieve integrated sustainable development.

   • Move beyond a narrow focus on pre-allocated sites, which constrains organic densification.
   • Deploy existing tools such as Local and Mayoral Development Orders more effectively to streamline sustainable projects.

5. Expand Public-Sector Intervention to Unlock Land

   Active public-sector leadership is essential for overcoming barriers to redevelopment and ensuring land is used for sustainable community benefit.

   • Prioritise public land assembly, remediation, and coordination, particularly on larger brownfield sites.
   • Increase government funding for brownfield remediation and development to unlock land for housing and contribute to urban regeneration goals under SDG 11.

1. Which SDGs are addressed or connected to the issues highlighted in the article?

• SDG 11: Sustainable Cities and Communities

  This is the primary SDG addressed. The article’s entire focus is on urban development, specifically the housing crisis, urban density, and city planning in Britain. It directly discusses making cities more sustainable and resilient by addressing housing shortages and inefficient land use, which is the core mission of SDG 11.

• SDG 8: Decent Work and Economic Growth

  The article explicitly links urban development to economic performance. It states that “the underperformance of major urban economies” is a key issue and that “higher-density urban development is essential for national prosperity.” This connects the physical structure of cities to their economic productivity, a central theme of SDG 8.

• SDG 9: Industry, Innovation and Infrastructure

  The article mentions “inefficient urban transport” as a problem stemming from low-density urban sprawl. Promoting higher-density development is an implicit strategy to enable more sustainable and efficient infrastructure, such as public transport systems, which aligns with the goal of developing quality, reliable, and sustainable infrastructure.

2. What specific targets under those SDGs can be identified based on the article’s content?

1. Target 11.1: Ensure access for all to adequate, safe and affordable housing and basic services.

   The article directly addresses this target by highlighting Britain’s “housing crisis” and quantifying the need for more homes. It calculates that if British cities matched the density of their peers, they would contain “at least 2.3 million additional homes,” directly tackling the issue of housing adequacy and availability.

2. Target 11.3: Enhance inclusive and sustainable urbanization and capacity for participatory, integrated and sustainable human settlement planning and management.

   This target is central to the article’s recommendations. The call to “accelerate national planning reform,” consider a “flexible zoning system,” and for local authorities to “focus on the entire urban core” are all measures aimed at improving sustainable urban planning and management. The analysis of the “density gap” and the proposal to build more “mid-rise housing” are specific strategies for more sustainable urbanization.

3. Target 8.2: Achieve higher levels of economic productivity through diversification, technological upgrading and innovation.

   The article connects the physical layout of cities to their economic output. The argument that fixing the “underperformance of major urban economies” is a key driver for densification directly relates to achieving higher levels of economic productivity. The report posits that a more efficiently built urban environment will unlock the “economic potential of its big cities.”

4. Target 9.1: Develop quality, reliable, sustainable and resilient infrastructure.

   The mention of “inefficient urban transport” as a core problem points to this target. Higher-density urban development, as advocated in the article, is a prerequisite for developing more efficient and sustainable public transport infrastructure, reducing reliance on private vehicles and improving overall urban mobility.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

• Residential Density Levels

  The entire report is based on a new dataset comparing residential densities. This is a direct indicator used to measure the “density gap” between British cities and their international peers. Progress would be measured by an increase in residential density in target areas like Manchester, Birmingham, and Leeds.

• Number of New Homes Built

  The article quantifies the housing shortage in specific numbers, such as the “2.3 million additional homes” needed overall and “500,000 more homes” in London. The number of new housing units constructed, particularly within the urban cores, serves as a clear indicator of progress towards Target 11.1.

• Proportion of Mid-Rise Housing

  The article identifies the “missing housing typology” as “mid-rise (3 – 9 storey) apartment buildings.” An indicator to measure progress would be the percentage of new housing completions that fall within this mid-rise category, tracking the shift away from low-density development.

• Rate of Brownfield Redevelopment

  The recommendation to implement “Brownfield Passports” and provide “more funding for brownfield remediation and development” implies that the rate of development on previously used land is a key indicator. An increase in the number of homes built on brownfield sites would signify progress.

• Urban Economic Performance

  Although not quantified with a specific metric in the article, the “performance of major urban economies” is cited as a key justification for densification. Implied indicators would include GDP growth, productivity levels, and job creation within these major urban centers, which are expected to improve as a result of the proposed changes.

4. Create a table with three columns titled ‘SDGs, Targets and Indicators” to present the findings from analyzing the article.

Source: centreforcities.org