One of the impacts of intense urbanisation is the Urban Heat Island (UHI) effect and the decrease in the air quality of urban centres. Both impacts will most likely get worse as cities grow and climate continues to warm up. As a result people in cities experience overheating and poor air quality, in their work environment and in their home.
The presentations in this session all indicated this is a real and present problem, but a policy focus on saving energy during the winter period is creating a built environment that is vulnerable to overheating now and possibly even more in the future.
As presented by Prof Rajat Gupta (Oxford Brookes University), the physics are simple; the more we seal up our buildings for winter warmth the more we rely on natural or mechanical ventilation for cooling them during the summer. In cities the use of external air to ventilate interior spaces might not be an option due to high pollution levels, noise and security issues. UCL is undertaking major research on the unintended consequences of decarbonising the built environment, looking at the risks of trying to deal with one problem in isolation – in this case energy efficiency – while creating another – in this case overheating risk – which could potentially be more dangerous for human health and well-being in the future.
The session revealed a major campaign to address overheating risk at policy and community level. Juliette Daniels presented the Climate UK initiatives in raising awareness and gathering evidence to influence policy. Zero Carbon Hub’s Rob Pannell introduced the beginning of a major work to gather evidence with the view to support government departments in addressing the issue.
The technical solutions and expertise, and the design tools to create buildings that perform well for both summer and winter exist. What is missing is the incentive. A good start would be the admission by both industry and government that overheating is a real issue. A key step then would be to require its treatment through building regulations and other industry standards. Ultimately industry experts should work with decision-makers to help them focus on where they can take effective action, and with residents to help them understand how to best protect themselves against the risks of overheating and poor indoor air quality.