Part of Ward Property Services UK LtdCondensation
How To Stop Condensation In Your Home
Why condensation happens
Warm air holds more water vapour than cold air. When warm, humid indoor air touches a surface cooler than its dew point, it can no longer hold that vapour and water condenses out. Everyday living adds a great deal of vapour: showering, cooking, washing up, drying laundry and simply breathing can easily contribute more than ten litres of water a day in a family home.
Older houses lost that moisture through draughts, open chimneys and single-glazed windows. Modern draught-proofing removed those losses without necessarily replacing them with controlled ventilation, which is why condensation complaints have risen alongside energy efficiency improvements.
Free changes that make a measurable difference
Put lids on pans, close the kitchen door while cooking and keep the extract running for fifteen minutes afterwards. Dry laundry outdoors when you can; if you must dry indoors, use one room with the door closed and a window slightly open, or a condenser dryer vented properly.
Keep heating steady rather than in short bursts. A house held at a moderate temperature has warmer wall surfaces and therefore a lower condensation risk than one that swings from cold to hot twice a day. Leave a gap between furniture and external walls, and open trickle vents.
Ventilation upgrades that work
Most bathroom fans move far less air than their rating suggests, because of long flexible ducting, missing shutters and short run times. A continuous-run humidistat fan with rigid insulated ducting is a modest job with a large effect. Kitchens benefit from a properly ducted extract rather than a recirculating hood.
Where a whole property is affected, positive input ventilation is often the most cost-effective answer. A loft-mounted unit gently supplies filtered air, diluting humid internal air and displacing it through natural leakage paths. In new or heavily refurbished homes, mechanical ventilation with heat recovery achieves the same with less heat loss.
When to get a specialist involved
If mould keeps returning after cleaning, if windows stream every morning through the winter, or if you cannot tell whether the damp is condensation or something structural, monitoring is the answer. Data logging temperature and humidity over a week gives an objective picture that guesswork cannot.
We also look for the physical reasons surfaces are cold: uninsulated lintels and reveals, missing cavity insulation, cold bridging at floor junctions. Raising surface temperatures and lowering humidity together is what produces a permanent result.
Common questions about this topic
What humidity should my home be?
Between 40% and 60% relative humidity is the comfortable, low-risk range. Above about 70% at a wall surface, mould can grow.
Do dehumidifiers stop condensation?
They reduce it effectively and are a useful interim measure, but ventilation and heating address the underlying cause.
Need professional advice?
Book an independent damp survey and get a written diagnosis for your property.