A cleaning enthusiast on TikTok has demonstrated a hack that stops condensation from forming on windows without spending money on an expensive dehumidifier, using washing-up liquid that costs as little as 62p.
With winter yet to arrive, condensation on windows can already build up in the morning, especially when the heating comes on for the first time. While it might seem harmless, condensation signals excessive moisture in the home, which can promote the growth of mould, cause paint to peel, and create musty odours. Even minor amounts of trapped moisture can harm wooden frames and result in black mould forming around the edges of windows.
Why condensation forms on windows
Condensation occurs when warm, moist indoor air comes into contact with cold glass. The rapid temperature decrease causes the moisture in the air to hit its dew point, resulting in visible droplets forming on the glass.
This phenomenon is particularly evident in winter, when the difference between heated indoor spaces and cold outdoor air is most pronounced. Condensation typically appears first around the edges of the pane, as these areas are the least insulated parts of the glass.
While dehumidifiers can effectively help rid the air of moisture, they can be pricey purchases. For a cheaper alternative, @cleanwithlilyx has shared a household hack using washing-up liquid, which can be picked up from supermarkets for as little as 62p.
How to keep windows drier with washing-up liquid
Sharing a video on TikTok that has amassed 1.5 million views, Lily noted that one of the main things she does to keep condensation away is to use washing-up liquid on her windows.
The hack involves applying dish soap to a window with a cloth and buffing it onto the entire affected section. Washing-up liquid works because the surface-active agent it contains reduces the surface tension of water, preventing moisture from forming into droplets and creating fog or condensation on the glass. Instead, the moisture spreads into an invisible layer, keeping the windows clear.
The cleaner said, “Put some Fairy Liquid on a cloth and get it buffed into those windows. This will stop the condensation sticking to your windows.”
Lily used Fairy Liquid washing-up liquid, but any dish soap can be used. This household staple can be picked up for as little as 62p at Aldi and Tesco, or from M&S for 65p and Sainsbury’s for 70p. When using the dish soap hack, it's important not to use too much to prevent streaks or bubbles from appearing.
Lily shared a video of the following day showing the results of how well the soap worked. She only applied the dish soap to the bottom half, and the next day, there was no condensation there, but there was on the top half of the window.
Other ways to prevent window condensation
From the previous video, Lily pointed out that windows need to be opened daily. She said, “Open those windows every single morning, even when it rains.”
Airing lowers indoor moisture levels, leaving less water vapour to condense on the surface of windows. Try airing for five to 10 minutes, adjusting the time to the room and weather.
Lily also claimed that disposable dehumidifiers can help and recommended hanging them behind curtains or blinds. She noted that this product will “all the damp water” collecting in the room.
Disposable dehumidifiers are compact and do not require electricity. They typically feature a layer of hydrophilic crystals that draw in and absorb moisture from the air. As the moisture flows through, the crystals slowly degrade and turn into liquid, which collects in the compartment below until it reaches capacity and is ready for disposal.
