The 'Wet Sheet Trick' Grandparents Used Before AC Is Going Viral — And It Actually Works
People are ditching their fans for a 100-year-old cooling hack, and sleep experts say there's real science behind it.
Before air conditioning existed, families survived brutal summers with one strange bedtime ritual: hanging a damp sheet in front of an open window. Now the trick is exploding online, with thousands swearing it cooled their bedrooms by several degrees overnight.
The science is surprisingly solid. As air passes through the damp fabric, evaporation pulls heat out of it — the same principle behind sweating. It's essentially a homemade swamp cooler that costs nothing but a little water.
There's a catch, though. The trick works best in dry climates. In humid states, the air is already saturated, so evaporation slows to a crawl and you mostly end up with a soggy curtain.
Still, fans of the hack say pairing it with a box fan makes even sticky nights bearable. One commenter put it best: 'My electric bill went down and my grandma is somewhere feeling extremely vindicated.'
