As the UK prepares for its third heat wave of 2026, residents seek ways to stay cool indoors. Building rules introduced in 2022 require new homes to be evaluated for overheating risks at the design stage. High-risk designs must be altered by architects.
With government plans for 1.5 million new homes by 2029 and continued climate warming, limiting overheating remains vital. In 2018, surveys found 4.6 million bedrooms and 3.6 million living rooms in England had overheated.
Loughborough University researchers tested pairs of semi-detached houses fitted with different shading devices to measure reductions in overheating. More work is required to ensure homes handle future high temperatures.
External shading offers one of the best passive cooling options and costs little to add. Tests showed it can cut indoor temperatures by over 6°C, aiding health and comfort. Such shading suits most new homes, including high-rise flats, similar to examples in France and Italy.
Higher insulation levels do not increase overheating risk, research confirms. Efficiency upgrades keep rooms warmer without causing discomfort when ventilation is used. Loft insulation reduces heat from above, while airtight construction blocks hot outdoor air during heat waves.
Earlier rules targeted winter heating needs, since cold-related deaths greatly outnumbered heat-related ones. Paired with new overheating standards that limit solar gain through windows, insulation and airtightness benefit buildings throughout the year.
Tests with automated devices that open windows and shades revealed occupant behavior affects overheating levels. Low-cost internet-linked temperature sensors could guide window use for better cross or stack ventilation.
Security and noise issues often prevent nighttime window opening in busy areas. Secure ventilation methods are needed to allow safe air flow without these concerns.
Ceiling fans provide
