Philip Box, Public Affairs and Policy Officer, UK Green Building Council.
The UK is already seeing more frequent and intense weather extremes due to climate change. Researchers have suggested that the likelihood of extreme rainfall in the UK has increased significantly. Likewise the heatwave of 2019, was reportedly made ten times more likely (PDF) – and 1.5°C to 3°C warmer – by climate change.
Our built environment is not prepared to cope with these conditions. Around 1.8 million people in the UK already live in areas of significant flood risk. If the frequent occurrence of major flooding events continues – which it has done in the UK nearly every year since 2007 – it is estimated that the number of homes at risk of flooding will rise by 40% to 2.6 million in as little as 20 years.
On overheating, the picture is similar. Roughly 20% of homes in England already experience overheating issues, even during cooler summers. Furthermore, the proportion of green space, which can provide a local cooling effect, has dropped from 63% to 55% between 2011 and 2016.
If global emissions continue at their current rate, extreme heat events like the summer of 2018 will become normal by 2050, occurring on average every other year. And by the 2070s, a hot day could be between 3.7 °C and 6.8 °C warmer than present.
So, what can be done? Well, any effective solutions will require coordinated action and a step-change in momentum, across all levels of government and from industry in demonstrating and developing the practical answers at scale.
As a first step, we must ensure we do not add to the scale of the problem we already have, and that means looking at new build standards and planning.
At a local level, as demonstrated in UKGBC’s New Homes Playbook, many local authorities have already begun to implement policies to address overheating in relation to planning. At a national level, the UK Government’s consultation on tackling overheating in building regulations is welcome, if long overdue.
Where there are still significant policy gaps, however, is on water. Policy Connect’s Bricks and Water series has made several excellent recommendations for national government in this area, for both water conservation and tackling flood risk. In terms of translating these into practice, both the Government’s planning reforms and interest in reforming Energy Performance Certificates (EPCs) would be possible avenues for this policy gap to be plugged.
However, it is important to note that issues with adaptation cannot be solved in terms of the technical specifications of a new property alone. Thinking about our neighbourhoods more broadly, studies have consistently shown the benefits of urban greening in addressing the urban heat island effect and sustainable urban drainage. As a result, many local authorities have been developing urban greening or green infrastructure strategies, aimed at not only considering ways to reverse biodiversity decline, but also how to harness the benefits of greenery in the face of extreme heat and flooding. Again, this is something the Planning reforms must encourage.
Moving beyond the policy levers to what can be done on the ground, approaches to nature-based solutions have been shown to deliver significant sustainable drainage and overheating mitigation benefits. A number of case studies of leading schemes help to demonstrate these benefits and approaches in action, across a range of different development types.
However, a focus on new buildings alone is not enough, with around 80% of homes likely to be standing in 2050 already built.
The need to retrofit our existing homes to reduce emissions also offers an opportunity to address overheating and resilience concerns. One option is to take a whole house approach, involving a retrofit coordinator who can produce a dedicated ‘whole house plan’. This enables a holistic approach to delivering improvements for the property, considering specific circumstances in detail and therefore preventing any unintended consequences from installing inappropriate measures. Local authorities can help to take this approach forward, which many are already doing so. UKGBC’s retrofit Playbook (PDF) provides more detailed information for local authorities on how this approach can be developed and examples of its success.
In the absence of central Government policy in this area, local authorities have led on the delivery of retrofit initiatives and programmes. You can see where these initiatives have been taking place on our interactive map, but there is still much more to do to ensure retrofit is tackled holistically, in a way that addresses adaptation as well as emissions reductions.
Adapting our built environment to cope with the impacts of climate change will require a fundamental shift in the way we approach development. The relevant considerations will have to be integrated comprehensively across associated government policy, both locally and nationally. For the industry, questions of how we build, and what materials to use, will become ever-more pertinent as the UK's climate changes the demands placed on our buildings.
With so many potential opportunities this year for these issues to start to be addressed, it is critical that we do not delay any further in preparing for the impacts of the climate crisis on the built environment.
This article is from our Local Path to Net Zero series.