Why Does Mould Get Worse in Winter?
It’s a common pattern in Warrington homes: the minute the temperature drops, condensation builds up on windows, walls feel cold and damp, and within weeks — black mould appears.
But why does it happen every winter?
At Weather Wise, we’re seeing a surge in calls from worried homeowners around Warrington reporting musty smells, window condensation, and mould behind furniture. And it’s no coincidence — cold weather triggers it all.
The Science: Warm Air + Cold Surface = Condensation
Cold air holds less moisture than warm air. In winter, when warm air from heating meets a cold wall or window, the moisture it was holding is released as liquid — this is condensation.
This moisture accumulates fastest:
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On windows overnight (bedrooms)
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On bathroom walls and ceilings after a hot shower
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Behind wardrobes or sofas on external walls
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In corners and ceiling lines where airflow is weakest
Left untreated, these areas quickly become prime mould zones.
Why It’s Worse in Winter
✅ Lower outdoor temperatures = colder walls and windows
✅ Longer showers and more cooking = more moisture indoors
✅ Closed windows & trickle vents = less air exchange
✅ Heating only in the evening = temperature swings that increase risk
If you have double glazing or a well-insulated home, it can actually trap moisture unless ventilation is properly balanced.
What Warrington Homeowners Can Do
🟢 Ventilation
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Keep trickle vents open in all rooms
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Use extractor fans during and after showers (at least 20 minutes)
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Fit a DMEV unit (Decentralised Mechanical Extract Ventilation) in high-risk rooms
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For whole-house control, consider a PIV system
🟢 Heating
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Use low, steady heating throughout the day rather than high bursts
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Avoid switching off radiators completely in unused rooms
🟢 Airflow
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Leave a 5–10 cm gap behind furniture on external walls
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Don’t dry clothes on radiators — use a vented tumble dryer or open window
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Avoid blocking air bricks or vents with insulation or boxes
What We Offer in Warrington
At Weather Wise Solutions, we’re not just here to clean the mould — we’ll help you prevent it coming back.
✅ Free moisture and ventilation surveys
✅ Installation of DMEV or PIV systems
✅ Salt inhibitor plastering if damage is present
✅ Professional mould cleaning and treatment
✅ Clear advice from Level 3 qualified surveyors
We’re trusted members of the Damp Proofing Association and the Federation of Damp
Book Your Free Mould & Condensation Survey in Warrington
https://weatherwiseuk.co.uk/pages/contact
Quick FAQs
Can I stop condensation without ventilation?
Not really — moisture has to go somewhere. Without proper ventilation, it stays inside your home.
What’s the difference between DMEV and PIV?
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DMEV = localised extract in bathrooms/kitchens
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PIV = whole-home ventilation from a central unit (usually loft-mounted)
Is winter the best time to act?
Yes — because this is when the problems are visible. Our solutions are designed to work year-round but are tested and diagnosed best during colder months.