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Condensation or dark spots of mildew around PVC windows are signs of damp. To prevent any further damage to the seal or walls it’s best if you fix the problem with the help of this simple guide.
Level of difficulty
Level 1: Beginner
Things you’ll need
The steps to follow
- With lighted incense, inspect the surround of the window frame. The incense smoke will detect a draught by blowing towards it. If there’s a slight draught, you should try to seal the edges of the window frame with a caulking gun and mastic
- Ventilate the room: leave the window open for about 5 hours during the day. Remember, however, to shut and lock your windows if you leave the house
- If the damp is more severe, install a dehumidifier in the room: turn the dehumidifier on and leave it for a day to suck the moisture out of the air
- If there is still a problem, inspect the area around the groove on your window sill. Unblock the groove on the window sill by cleaning the debris out with a vacuum or a brush. Reapply mastic sealant to the window sill. If the window sill is old, you might want to replace it
Don’t want to DIY? Get recommended window specialists for your home improvement job.
Please note that all our DIY guides and ‘Expert answers’ advice have been written strictly for reference only. Rated People do not accept any liability for any damage caused to an individual, property or anything else as a result of following our DIY guides and using our ‘Expert answers’ advice.