💧 Water & Weather
How to Keep Your Home Cool in a Heatwave
Block the sun, time your ventilation, and reduce heat you make indoors. Cheap steps beat a portable air conditioner more often than you might think.
Marcus Ibe · Sep 28, 2026 · 6 min read · 4 steps
Homes built for cold climates can trap heat badly during hot spells, particularly top-floor flats and rooms with large south- or west-facing windows.
The goal is to stop heat getting in during the day and flush it out at night.
Block the sun before it enters
External shading — awnings, shutters, or even a sheet hung outside a window — is far more effective than internal blinds, because it stops the heat before it reaches the glass. Inside, light-coloured blinds or curtains with a reflective lining help; keep them closed on sunny sides during the day.
Ventilate at the right time
Keep windows closed when it is hotter outside than inside. Open them in the evening and overnight when the air cools, ideally on opposite sides of the home to create a cross-breeze. Close them again in the morning to trap the cool air.
Reduce heat you create
- Switch off unused appliances and chargers
- Cook early, use the microwave, or eat cold meals
- Run the dishwasher and washing machine at night
- Swap old bulbs for LEDs, which produce little heat
Longer-term fixes
Loft insulation helps in summer as well as winter by slowing heat coming through the roof. Reflective window film, external shutters, and trees or climbing plants on sunny walls all reduce heat gain. Check on older neighbours and anyone vulnerable during extreme heat, and follow local health advice.
This is general home-maintenance information, not professional advice. Building codes, permits, and safe practices vary by location — consult a licensed contractor, electrician, or plumber for work beyond your experience.