![\"Members](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2026\/03\/london-assembly-planning-committee-2000px.jpg\")
London Assembly Planning and Regenration Committee. Image: GLA webcast.<\/p>\nLondon Assembly Planning and Regenration Committee. Image: GLA webcast.<\/p>\n
Londoners face a unique overheating risk in their own homes due to climate change impacting a densely built environment and an outdated planning and design system, the London Assembly has heard.<\/p>\n
Extreme heat is becoming an increasing issue in London, with more than a tenth of the 3,271 heat-related deaths in 2022 \u2014 which saw record temperatures across the UK \u2014 in the capital.<\/p>\n
This is due to the city\u2019s increasing density of buildings and roads leading to the urban heat island (UHI) effect, where residents experience temperatures up to 10 degrees higher than in the suburbs or countryside as heat is absorbed there.<\/p>\n
City Hall is currently drafting London\u2019s Heat Risk Delivery Plan<\/a> in a bid to cool down residents; this is despite summers already becoming hotter and drier every year. This could include \u201ccool spaces\u201d around the city, thousands of water refill points and plans to plant thousands more trees.<\/p>\n While this may go some way to protect Londoners making their way around the city, people are still at risk of overheating in their own homes.<\/p>\n Currently, the London Plan encourages new developments to adopt \u201cpassive\u201d cooling measures \u2014 such as trees, green roofs, and shading \u2014 rather than \u201cactive\u201d measures, such as air conditioning (AC).<\/p>\n The 2021 London Plan states that the spread of active measures such as AC systems is \u201cnot desirable as these have significant energy requirements and, under conventional operation, expel hot air, thereby adding to the urban heat island effect\u201d. Just five per cent of British households have AC units.<\/p>\n On Tuesday 10 March the London Assembly Planning and Regeneration Committee<\/a> was told that the \u201ccooling hierarchy\u201d present in the current London Plan \u2014 which means that active cooling is only implemented as a last resort \u2014 was \u201cunhelpful\u201d.<\/p>\n Ed Hezlet, head of energy at the Centre for British Progress, said: \u201cIt appears that the passive measures, particularly things like shading are very important. But fundamentally, the real health risks are the heatwave conditions and therefore, passive and active measures are doing slightly different jobs.<\/p>\n \u201cWe want passive measures to ensure that people aren\u2019t locked in to properties that force them to use air conditioning more than they otherwise might, that would cost them money.<\/p>\n \u201cBut I would say that the active measures are very important with dealing with tail risks of very, very high temperatures, and I think the way the hierarchy is framed puts these two technologies in opposition much more than working together with one another.\u201d<\/p>\n He said that as temperatures increase, a failure to encourage efficient active cooling systems means \u201cpeople will go out and buy lots of inefficient devices\u201d.<\/p>\n \u201cTherefore, it makes a lot more sense to think about how we incorporate active cooling efficiently in advance,\u201d Hezlet added.<\/p>\n Dr Anna Mavrogianni, professor of sustainable, healthy and equitable built environment at University College London, noted research showing that AC installation rose almost sevenfold between 2011 and 2022 showed it was a phenomenon that \u201cwe cannot ignore\u201d.<\/p>\n She supported Hezlet\u2019s point that active and passive cooling should work together, rather than in a hierarchy,<\/p>\n \u201cPassive cooling strategies could potentially empower residents so if there is a blackout there are solutions there that could maintain comfortable indoor temperatures for a longer time and also they could reduce overall cooling loads,\u201d she said. <\/p>\n Earlier in the session, Polly Turton from Shade the UK had warned against the \u201cgrowing demand for active cooling\u201d, which is \u201cputting additional strain on our efellownergy grid and causing a knock-on effect on infrastructure\u201d.<\/p>\n She said the primary issue with overheating was tackling the \u201chuge culture shift\u201d in the development and design sector to more effectively \u201cplan, design and manage our buildings in London\u201d to have better cooling adaptations.<\/p>\n Dr Joel Callow, founding director of Beyond Carbon, said current regulations had trapped designers \u201cin a system with contradictory aims\u201d.<\/p>\n He added: \u201cThe planning system pushes for daylight criteria, which means larger windows, which goes against cooling criteria. Shading is not a historic part of our architectural vernacular \u2014 it\u2019s very hard to convince planners to let us install shading, because it might not look like a British building.<\/p>\n \u201cThe principal challenge is that both planning and building regulations cannot both be met. A well-designed, modern apartment with all the windows closed should stay cooler than the outside temperature.\u201d<\/p>\n Mavrogianni noted: \u201cThere is a lot of emphasis on having large glazing areas with no provision for shading or solar control. Windows can be a significant source of solar heat gains \u2014 having an unopenable window can contribute to overheating.\u201d<\/p>\n London Assembly Planning and Regeneration Committee, Tuesday 10 March 2026. Agenda<\/a>. Webcast<\/a>.<\/p>\n![\"Ed](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2026\/03\/ed-hezlet-2000px.jpg\")
Ed Hezlet, head of energy at the Centre for British Progress. Image: GLA webcast.<\/p>\n![\"\"](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2026\/03\/dr-Mavrogianni-2000px.jpg\")
Dr Anna Mavrogianni, professor of sustainable, healthy and equitable built environment at University College London. Image: GLA webcast.<\/p>\n![\"Dr](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2026\/03\/khosravi-turton-2000px.jpg\")
Dr Mehri Khosravi, senior research fellow, University of East London; Polly Turton head of climate action and public health, Shade the UK. Image: GLA webcast.<\/p>\n