Find, free, clean and correctly position your window trickle vents to cut everyday condensation and mould risk.
TV-01Find every trickle vent in the propertyLook along the top of each window frame, inside and out, for a narrow slotted vent above the glass. Not every window has one, but check kitchens, bathrooms and bedrooms first, as these produce the most moisture. Make a quick list of which rooms have vents and which don't.
TV-02Test the opening mechanism on each ventSlide or flip the small lever or slider on each vent to see if it moves the full distance from closed to open. Many vents seize up from years of paint, dust or damp and can feel stiff at first. Don't force a jammed lever, as cheap plastic mechanisms snap easily.
TV-03Free a stuck or painted-over ventRun a flathead scraper gently along the hinge line to score through old paint sealing the lever shut. A drop of light lubricating oil on the pivot helps if it's still stiff after that. Wipe away any excess oil or paint flakes, then test the lever again until it moves smoothly.
TV-04Clean the vent slots and filterBrush dust, cobwebs and dead insects out of the slots with a soft brush, then wipe over with a cloth and a little mild detergent in water. Some vents have a removable insect mesh or acoustic pad inside — slide this out, rinse it separately, and let it dry fully before refitting.
TV-05Set kitchen and bathroom vents to stay openLeave trickle vents open all the time in kitchens and bathrooms, even in winter, since these rooms make the most steam and moisture. Only close a vent briefly during a hard storm or extreme cold spell, then open it again once conditions ease.
TV-06Set vents in bedrooms and living roomsLeave these vents on their lowest open setting rather than fully shut. A small steady trickle of fresh air stops moisture building up overnight, which is when condensation forms on cold glass and frames.
TV-07Check results over the following weekLook at each window first thing every morning for a week and note whether condensation on the glass has reduced. If damp patches or mould keep coming back despite open vents, the room may need extra help — an extractor fan, a dehumidifier, or a bigger vent — rather than the vent alone solving it.
TV-08Tidy upWipe down windowsills and frames to remove any paint flakes or dust from cleaning. Put the scraper and oil away safely, and bin any old filter pads you replaced.
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