As temperatures soar, heating and cooling specialists BOXT are available to reveal the common mistakes that trap heat indoors — from opening windows at the wrong time and relying too heavily on fans, to overlooking hidden heat sources such as cooking, electronics and even phone charger.
The warning comes as demand for cooling solutions continues to surge, with BOXT reporting a 249% year-on-year increase in air conditioning sales across the UK during May and June. Growth has been seen in every region, with some hotspots recording increases of more than 1,700% compared to the same period last year.
Experts can explain why bedrooms are often the hottest rooms in the house, how homeowners can stop their property becoming a “greenhouse”, and why more households are beginning to view cooling as an essential part of modern home comfort rather than a luxury.
Stop turning your home into a greenhouse
“The biggest mistake people make during a heatwave is waiting until their home already feels unbearably hot before taking action.
By that point, walls, floors and furnishings have already absorbed heat throughout the day. A few simple steps early on, such as closing blinds and limiting direct sunlight, can help stop your home turning into a greenhouse.”
More open windows doesn’t always mean a cooler home
“People often assume more airflow automatically means a cooler house, but that’s not always the case.
If it’s hotter outside than it is indoors, opening windows can actually speed up the warming process. Timing is everything when it comes to ventilation wait until the air has cooled down in the evenings to open up your windows; this will let the warm air out of your house and let it cool down overnight”
Your bathroom fan could be helping more than you think
“Most people don’t associate extractor fans with staying cool, but they’re useful for removing warm, humid air that can make a home feel uncomfortable.
Every little bit helps during a heatwave, particularly in rooms where heat and moisture build up quickly.”
Hidden heat sources are everywhere
“When people think about staying cool, they focus on the weather outside. What they often forget is how much heat they’re generating inside.
Cooking, drying clothes, running electronics and even charging devices all contribute to rising indoor temperatures.”
Fans cool people, not rooms
“There’s a common misconception that fans reduce room temperature. In reality, they’re designed to make you feel cooler by moving air across your skin. The room itself remains largely unchanged, which is why fans work best alongside other cooling measures.”
Bedrooms are often the hottest room in the house
“Many people struggle to sleep during a heatwave because heat naturally rises and becomes trapped upstairs. People are shocked by how hot loft spaces get too. In really warm weather, lofts trap heat, and all that heat slowly filters down into bedrooms upstairs well into the evening. The upstairs of a home can quickly become 5–10°C hotter than downstairs, which is why loft conversions and top-floor bedrooms are often the hardest spaces to keep cool.”
Portable AC isn’t always the bargain it appears
“Portable air conditioning can seem like an easy solution, but it isn’t always the most effective one. Many units have to work much harder, and use more energy, to deliver the same results as a fixed system, particularly during prolonged periods of hot weather.”
Cooling is becoming part of modern home comfort
“Air conditioning is often viewed as something reserved for hotter climates, but attitudes are beginning to change. Modern systems are much more efficient than people think and, unlike fans, they actually cool the room instead of just moving warm air around. Many systems can also heat your home in winter too, making them useful all year round. BOXT offers finance options from around £29.90 per month alongside seasonal offers such as £250 off installations, helping make air conditioning feel far more accessible for UK homeowners. As summers become warmer and heatwaves last longer, more homeowners are looking at cooling in the same way they view heating — as an essential part of keeping a home comfortable year-round.”
