Heatwaves and Housing : Planning for Climate Change

I am probably in the minority of people who did not enjoy the recent spell of extremely good weather*. Now the sunny snap appears to be over, however, it is a good time to think about how well equipped we are to deal with the increasingly hot summers that are likely to be heading our way.

As the Guardian article, below, makes clear, managing hot weather is a rather novel challenge in the UK. Historically, we have a temperate climate, and are more likely to face rain and the occasional cold snap than prolonged warm spells. Which may have given rise to that great British tradition of moaning about the weather. The general consensus amongst climate change scientists, however, is that heat waves are going to become more common both in the UK and across the globe.

This poses somewhat of a challenge to planners, who have historically focused on ensuring new homes are protected from flooding and well insulated against the cold. We now also need to take account of the need to design homes which are also capable of being kept cool, and are not at risk of overheating in hot weather.

The recently revised NPPF** does now contain a specific reference to the need to address the need to mitigate temperature rises and the risk of overheating in paragraph 149, which reads as follows: 

"Plans should take a proactive approach to mitigating and adapting to climate change, taking into account the long-term implications for flood risk, coastal change, water supply, biodiversity and landscapes, and the risk of overheating from rising temperatures. Policies should support appropriate measures to ensure the future resilience of communities and infrastructure to climate change impacts, such as providing space for physical protection measures, or making provision for the possible future relocation of vulnerable development and infrastructure. "

but the reference is not carried through into the decision-making parts of the same chapter, which talk about climate change in more general terms and tend to focus on the need to cut greenhouse emissions and plan for flood resilience.

There are more specific policies on the need for new housing developments to avoid overheating in the new draft London Plan (Policy D4 paragraphs E and F), but little guidance on how this is to be achieved. 

I do not know how many adopted local plans currently contain policies or guidance on designing dwellings appropriate for hot weather, but I am willing to bet that it is probably a fairly small percentage.

As such, more thought is likely to be needed about how best to design and plan for homes that can better deal with extremes in temperature - regardless of the time of year. Perhaps lessons can be learned from countries that already deal with more extreme heat and cold than is common for the UK...  if nothing else, it would be a really good excuse for a summer holiday!

* In my defence,  I am quite heavily pregnant  at the moment, so the regular 30 degree days were somewhat challenging.

** Yes,  I know I have been rather quiet on this front recently, but there will be more to follow - I promise.

Even if we avoid dangerous climate change by cutting greenhouse gas emissions, we face another three to four decades of heatwaves, increasing in frequency and intensity.

But overheating has largely been overlooked by developers and planning authorities. Our planning regulations are simply not fit for purpose: they do not provide enough guidance to developers about the threats currently posed by heat, let alone how these threats are likely to evolve over the lifetime of a building.”