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Staff blog

Could gentle density mitigate climate breakdown?


As part of our special blog series, Queen's Voices on COP26, Dr Agustina Martire, Senior Lecturer in Architecture in the School of Natural and Built Environment, explains why we need to reimagine our built environment to create a more sustainable and inclusive future for our cities.


Most of the world is now aware of the socially and ecologically disastrous consequences of our way of life. Excessive consumerism, fossil fuels/car dependency and excessive waste, have consistently damaged the environment we live in and destablised the climate. We know that there is very little time left to avoid a climate catastrophe. Yet, the efforts to limit global warming have fallen radically short.

Transport and construction are disproportionately responsible for this phenomenon. In the EU, private cars are responsible for over 60% of the carbon footprint of all transport, with transport taking 27% of the full share of carbon emissions in the EU. This means 16% of the European carbon footprint lies with private cars. Meanwhile 25% of greenhouse gases come from the construction industry alone, including demolition, construction and production of materials.

Belfast is one of the most car dependent cities in the UK, with the average person making over 80% of journeys by car.

While studies are being carried out at Queen’s to understand this phenomenon, enough is understood of the past planning of the city to assume that much of that car dependency is due to the way in which the city was planned and designed since the 1960s.

The ‘demagnetisation’ of Belfast since the Belfast Development Plan of 1969 (research by Sterrett, Gaffikin, Ellis and Murtagh explore this) produced a suburban landscape that became largely dependent on individual cars. This was a global phenomenon, but Belfast was particularly affected by the new layout of roads and housing. This was based on a road design that reduced the density of the population of Belfast City, particularly affecting working class communities, who lost connections with the city centre and are disproportionately affected by increased deaths from traffic and air pollution.

This process left a large amount of vacant land in the inner city area, and new planning policy is aiming to repopulate those areas, including the ambition of the Belfast Agenda to provide housing for 66,000 people. But all new proposals for housing in Belfast are still either high density and high rise or very low density sprawl. And most of these proposals tend to be devoid of social housing, therefore doing little to deliver for people’s rights to a home. Meanwhile, many of the new developments are exclusively housing, far from all other functions that make a city liveable.

High density and high rise may deal with new cars in the city, as people living near their work are more likely to walk or cycle, but the carbon footprint, energy consumption and maintenance of high rise buildings has been proven to be unsustainable. On the other hand, the low density of suburban sprawl requires the development of greenfield and brownfield sites and an increase of car dependency.

The relatively new idea of Gentle Density could deal with the impact of both transport and construction by providing a medium density built fabric, which encourages more sustainable modes of transport due to its proximity to places of work and public services such as medical facilities and recreation facilities.

Gentle density is about both the built fabric and the processes to achieve it. It fosters a medium density of about 4 stories, with green private and common spaces, while aiming to have minimum disruption on the existing fabric by proving infill buildings. Gentle Density also provides the ideal built environment for the 15-minute city, which has roots in ages long built fabric, but has been brought back into mainstream discussion more recently as an alternative to sprawl.

So far, in Belfast there are very few planning proposals that even consider this type and scale of new housing or built fabric. The Department for Communities, Department for Infrastructure and Belfast City Council are interested in new ideas for housing and urban development. Hopefully the relationship between Queen’s researchers and these organisations will continue growing so that conversations about these issues can be tackled at the government scale.

The status quo is not an option, and neither is ‘greening’ this status quo a viable option either. We need a paradigm shift in how we reimagine our built environment and how it can be sustainable, socially inclusive and promote health, economic vitality and wellbeing. Continuing to build a high-rise high-density city centre and low-rise low-density suburbs means ignoring the climate emergency. Alternatives exist; gentle density, mixed use, mixed tenure and public participation can foster a less damaging growth and a more inclusive future for our cities.


Photo: Dr Agustina Martire, Senior Lecturer
Dr Agustina Martire, Senior Lecturer
School of Natural and Built Environment
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