It comes as city dwellers are struggling to live in poorly designed modern tower blocks during the current heatwave, with temperatures soaring to 36C this week.
Many new-build blocks of flats feature apartments with large windows only on one side – blocking natural ventilation – and lacking external shading.
The problem is particularly acute in London, where box-shaped flats rapidly multiplied across the capital during Boris Johnson’s mayoralty. These buildings are so closely associated with the city that the architectural style has been dubbed New London Vernacular.
Residents of such tower blocks told Bloomberg on Wednesday that the heat was “unbearable” and “life-threatening”. One tower block dweller said their family’s triple-glazed windows were shattering in the heat.
Create Streets said that planning rules had created these problems.
Recent rules for windows, introduced in 2022 by Michael Gove, the then-housing secretary, have effectively made it impossible for builders to include sash windows in new builds. These windows allow air to circulate in ways other windows can’t, because of their top and bottom openings.
The think tank said ministers should also redraft rules to support the use of external shutters, which are commonplace across southern Europe and are effective at blocking heat from the sun.
They were once commonly used across Britain, but current rules take no account of manual shutters, providing little incentive for builders or homeowners to install them.
Create Streets also urged ministers to relax planning rules so that homeowners can fit external shutters and retractable awnings without needing to seek planning permission.
It also called for more tree planting by councils. Researchers have estimated that streets with trees can be five to 15 degrees cooler than those without.
