If you've been looking for ways to stay cool this summer, one answer could be right at your doorstep – or a few inches above that.
Sash windows, a common feature in many period homes, are designed to regulate temperature when it's hot, but according to industry experts, few know how to use them properly.
"The design of many Georgian and Victorian buildings incorporates natural cooling systems," says Nick Smith, owner and director of NJS Sash Windows. "Most homeowners have no idea these windows were designed to naturally cool a room."
Instead of simply flinging open one sash as wide as possible, both panels need to be moved strategically.
"By opening both the top and bottom sash, air circulates naturally, and warm air escaping through the top sash is replaced with cooler air drawn in through the bottom sash," explains Nick.
"This natural cooling airflow is done without the use of electricity."
Not entirely convinced? The University of Cambridge did research into the fluid mechanics of sash windows and found that they can, in fact, provide highly effective natural ventilation if opened correctly.
According to the findings, you'll achieve the best results when opening both panels by the same amount, creating what scientists call 'displacement ventilation': an effect where warm air naturally rises and exits through the top opening, while the cooler outside air is drawn in at the bottom.
Crucially, you don't even need to fling them wide open. NJS recommends opening the top and bottom sashes by just 10 to 15cm.
It should be noted that this works best in the early mornings and evenings, when the air outside is cooler than that indoors. During the day, it's generally recommended to keep windows and curtains shut to avoid heat building up in the first place (check out the caveman method if you haven't already).
So, instead of pointing your fan out of your window to flush the hot air out, simply utilise the forgotten ingenuity of sash windows and enjoy a cooler room in minutes.
More heatwave advice:
- How to stop a small home overheating this summer
- These 5 heatwave mistakes are making your home feel even hotter
Cooling summer essentials
Comfortably Cool 1 Tog Duvet
ChillPill 3-in-1 Fan, Mist & InstaChill System
DREO 7500 BTU Portable Air Conditioner
Emma Premium Pillow
Wanda Sachs is the Multiplatform Writer for Country Living and House Beautiful, exploring the latest in gardening, wildlife and sustainable living alongside interiors and property. She is particularly interested in human-interest stories, the intersection of design and pop culture, and the evolving relationship between urban and rural life. Previously, she served as Associate Editor at The Berliner in Berlin, where she reported on culture and fashion. Wanda studied English and German at the Goethe University Frankfurt and Exeter University.
