You don't always need to invest in a pricey aircon unit or fan in order to stay cool at home, according to experts.11:30, 11 Jul 2026We're in the midst of yet another heatwave here in the UK, and while this one isn't quite as intense as the last, it's still stifling. With 'above average' temperatures on the way for August too, according to the Met Office, many Brits will be wondering the best way to keep their homes cool.‌We are constantly being told not to open windows and doors during the day, and to keep curtains and blinds shut when the sun is at its peak. A fan or an aircon unit seems like the obvious choice, but according to experts, there's actually a simple curtain trick that can work very well at cooling down the rooms in your home that need it most.‌Kate O’Brien, Style Consultant at Swift Direct Blinds, has recommended 'window stacking' as the perfect way to protect your home from heat this summer. It uses the layering of window treatments, such as curtains and blinds to help keep your home cooler, taking fabrics and styles into consideration.‌What is window stacking?Window stacking involves using two or three different coverings to give you more control over the temperature of your home during a heatwave - and it doesn't have to cost an arm and a leg.Thermal and blackout curtains are the heaviest, and typically the outer layer, in a window stack.‌Kate said: "We often associate ‘thermal’ with retaining the heat, but the barrier that they create also blocks heat and sunlight in the warmer months – as well as stopping already cool air from escaping the home."When choosing a thermal blind, it’s important to choose a light-coloured fabric as they tend to absorb less sunlight than a dark-coloured blind.Shutters or blinds are a great daytime layer for controlling the direction of sunlight. You can tilt the slats up or down to redirect the light around the room, and prevent glare from the sun, or close them completely to create a light layer that prevents cool air from escaping and hot air from entering the home.‌Kate says these are the best choice for households that want greater control over how much light or heat there is.And finally, sheer curtains can be a stylish and useful addition to a window stack. They work similarly to shutters, reducing sunlight without darkening the room.Article continues belowIf you still want to feel a breeze, these are perfect, as they keep the room light and airy at the same time.Alternatively, double roller blinds blackout the room at night and let light seep through during the day. They have two layers of fabric on a single bracket, which allows you to switch between a sheer privacy layer and a blackout layer.Double roller blinds also have the added benefit of greater insulation, with the double layer keeping rooms cooler in summer and warmer in winter.