Rooms will keep cool without a fan with ‘green’ item on windowsill

With another sweltering hot day in store for the UK, many homeowners will be looking for smart ways to keep their homes cool without relying on electric fans. Experts, like those from the British Red Cross, are pointing out different methods to reduce indoor heat.

These methods include savvy shading, proper ventilation, and effective heat management. An often-overlooked strategy for temperature control is using houseplants.

Placing leafy green plants on windowsills that are exposed to direct sunlight can act as a natural filter. These plants help absorb a portion of the sun’s heat and, through a process similar to perspiration, release moisture into the air. This not only provides a visual shield but also helps keep the immediate area nearby slightly cooler, without the need for an electric fan.

Explaining the benefits of placing leafy green indoor plants by windows exposed to direct sunlight, the British Red Cross said: “Indoor plants can act as a natural filter for sunlight.” It added: “When placed near windows, they help absorb some of the sun’s heat and release moisture, which cools the air inside your home. Potted plants are semi-permanent solutions that are simple and non-invasive, making it a perfect option for anyone, including renters.”

On Gov.uk‘s ‘Beat the heat: keep cool at home checklist’, it also mentions the benefit of using plants. It says: “Growing plants outside can provide shade, which may be particularly helpful in front of south-facing windows, while plants inside may help cool the air.”

As per NASA’s Earth Science Study, plants play a role in cooling our planet. Their leaves provide ground-level shade, creating cooler areas. On a larger scale, their ability to photosynthesise contributes to precipitation, which helps lower the Earth’s temperature.

Even in hot, stuffy homes, when it gets too warm, plants release extra water through their leaves. This process, known as transpiration, not only cools the plants but also reduces the air temperature around them.

The Plants and Flowers Foundation has listed several of the ‘best’ house plants that help keep rooms cool. Just be sure to check that these are suitable if you have any animals or children at home. These include:

• Sansevieria (snake plant) – incredibly heat-resistant, tolerates bright window light
• Aloe Vera – best option for a sunny, warm windowsill
• Palm – thrives in bright, indirect light
• Ficus Benjamina (weeping fig) – but avoid hard, direct sunlight
• Ficus Elastica (rubber plant) – prefers bright, indirect light
• Aglaonema (Chinese evergreen) – prefers indirect, medium light

There are other ‘cooling’ tips the British Red Cross recommends, such as hanging thermally lined curtains on windows exposed to direct sunlight. It explains: “Thermally lined curtains have a special backing that not only blocks sunlight but also insulates against heat. This keeps your rooms cooler during the day by preventing heat from entering through the windows.”

Another option is to use blackout blinds or curtains, as it says: “Blackout blinds are made from thick fabric that blocks the majority of sunlight. Pu͵ing them up in the warmer months and taking them down when it’s cooler helps you manage the temperature inside your home more effectively. Try using a blanket as a low-cost option.”

It also recommends keeping warm air out during the day and ventilating at night. “Opening a window doesn’t always mean you’re cooling your home. In fact, if the air outside is warmer you could risk making it worse,” it said.

“During the hottest parts of the day, it’s best to close windows to keep the warmer air out. Check the forecast to gauge when temperatures are starting to rise. Wait until the cooler times of the day to open windows. When they are open, you can creating a breeze in your home by opening different windows to help air to circulate.”