How to Keep Your Home Cool During a Heatwave — Tips That Actually Work
British houses are built to retain heat, not release it. A spell of hot weather in May or June exposes this quickly, particularly in older properties with solid walls and small windows. If your home has turned into a radiator, here are the tips that actually make a difference, and the ones that are more myth than method.
Close the windows during the day
This is the one that catches people out most. The instinct when it is hot is to open everything and let the air in. But if the outside temperature is higher than inside your house, opening windows lets that hot air pour in and warms the rooms up faster. Keep windows closed and curtains or blinds drawn on the sunny side of the house during the hottest part of the day, roughly 10am to 5pm. You are trying to keep the heat out, not ventilate.
Open windows again in the evening once the outside temperature drops below your indoor temperature. If there is any breeze, open windows on opposite sides of the house to create a cross draught. A few hours of cooler night air will drop the indoor temperature considerably before you close up again in the morning.
Block the sun before it heats the glass
Glass is highly efficient at transmitting heat. A south or west-facing window in direct afternoon sun can raise a room's temperature significantly within an hour. External blinds or shutters are the most effective solution because they stop the sun's energy before it hits the glass. If you do not have these, thick curtains or blackout blinds on the inside are the next best option. Lighter blinds that let the light through while blocking some heat are better than nothing but significantly less effective than something that fully blocks the sun.
Reflective window film is an inexpensive solution that can be applied to existing glass and noticeably reduces solar heat gain, particularly on large windows. It is worth considering on rooms that get the worst of the afternoon sun.
Sleep lower down
Heat rises, which means the top floor of your home will always be warmer than the ground floor, sometimes by several degrees on a hot night. If you have a spare bedroom or sofa bed on the ground floor or lower level, using it during a prolonged heatwave is genuinely effective rather than just a dramatic gesture. The same applies to children: if their bedroom is in the loft or top floor, moving them to a cooler room for a few nights will make a real difference to their sleep quality.
For bedrooms you cannot move out of, cotton sheets and a single light layer are far better than anything synthetic. A frozen water bottle wrapped in a cloth at the foot of the bed, or a cool damp towel, can provide enough relief to get off to sleep.
Use fans strategically, not just hopefully
A fan does not cool the air. It moves it, and the cooling effect comes from evaporation off your skin. This means a fan pointed directly at you is considerably more effective than one pointed at the room in general. It also means fans work better in lower humidity, which is typically the case in the North West compared to the south.
The ice-in-front-of-the-fan trick does genuinely work on a small scale. A bowl of ice or a frozen water bottle placed in front of a desk fan will lower the air temperature in the immediate area by a few degrees for as long as the ice lasts. It will not cool a room, but it will cool the space around you.
At night, a fan positioned to draw air in through a window on the cooler, shadier side of the house and push it out on the warmer side creates a basic ventilation flow that can meaningfully lower the overnight temperature in a room.
Turn off the things that generate heat
Appliances generate more heat than most people realise. The oven is the obvious one: avoid using it during the hottest part of the day. A slow cooker uses significantly less energy and generates far less radiant heat than an oven, and works well for meals that do not need high heat. A microwave generates less heat than a conventional oven for the same cooking time. An air fryer is also a lower-heat alternative for smaller portions.
Lights, particularly older halogen or incandescent bulbs, generate noticeable heat when left on. If you have not already switched to LED throughout the house, a heatwave is a good reminder that LED bulbs generate a fraction of the heat of older types. Computers, TVs, and gaming consoles also generate meaningful heat in the rooms they are used in. Unplugging them at the wall when not in use removes a small but real heat source.
Cool yourself, not the room
Cooling the room costs money and takes time. Cooling yourself is immediate and free. A cool shower in the evening before bed lowers your core body temperature and makes sleep significantly easier. Wrists and ankles are areas where blood vessels run close to the surface, so running cold water over them or applying a cold damp cloth is disproportionately effective relative to how it sounds.
Staying hydrated is obvious advice that most adults do not actually follow properly during hot weather. Room temperature water is absorbed faster than very cold water, which is counterintuitive but true. The goal is to drink consistently throughout the day rather than in large amounts when you are already feeling the effects.
Check on neighbours, particularly older ones
Heatwaves are a genuine health risk for older people and those with certain medical conditions, a quick knock on the door or a phone call during a prolonged hot spell costs nothing and could matter considerably. It is the kind of thing that makes a community feel like a community.
