How to Stop Condensation on Windows: UK Homeowner Guide

Condensation on windows is a common issue, especially during the colder months. Those misty, water-streaked panes aren’t just annoying — they can lead to mould, damp, and even damage to window frames and walls if left untreated.

The good news? There are several ways to stop condensation — from quick daily habits to long-term home improvements.

What Causes Condensation?

Condensation happens when warm, moist air hits a cold surface, like your window glass. The moisture in the air turns into droplets when it can’t stay as vapour.

Everyday activities like cooking, showering, boiling the kettle, drying clothes indoors, and even breathing contribute to indoor humidity. Combine that with poor ventilation or single glazing, and your windows become a magnet for moisture.

Quick Fixes to Reduce Condensation

Start with small daily changes to reduce moisture in the air:

• Open windows for short bursts (10–15 minutes) every day to let moisture escape, especially after cooking or showering

• Use extractor fans in kitchens and bathrooms — and leave them running a bit after you’re done

• Keep internal doors closed when producing steam, to stop it spreading

• Wipe down windows and sills daily to prevent moisture build-up turning into mould

• Use a window vacuum or microfibre cloth to remove condensation quickly in the morning

These changes help manage condensation but won’t solve the root problem if your home is overly humid.

Longer-Term Solutions

1. Improve Ventilation

If your home doesn’t get enough airflow, condensation becomes harder to control. Consider fitting:

• Trickle vents on windows

• Air bricks or passive vents in older homes

• A Positive Input Ventilation (PIV) system for constant air circulation

Good airflow keeps moisture moving — and stops it collecting on your glass.

2. Use a Dehumidifier

A decent dehumidifier will pull moisture out of the air, lowering humidity and reducing condensation. These are especially useful in bedrooms, bathrooms, or rooms where you dry clothes indoors.

Even small plug-in units can make a noticeable difference — and many models let you set a target humidity (ideally 40–60%).

3. Upgrade Your Windows

If you’ve got single-glazed or older double-glazed units, you’re more likely to see condensation. Upgrading to modern A-rated double or triple glazing can dramatically reduce cold spots and condensation.

Also check for blown double glazing (fogging between the panes), which may need replacing.

4. Insulate Cold Surfaces

Cold walls and windows attract condensation. Adding insulation, whether through wall treatments or thick curtains and blinds, can help reduce temperature differences and minimise condensation risk.

Other Handy Tips

• Avoid drying clothes indoors, or do it in a well-ventilated room with a dehumidifier nearby

• Keep furniture slightly away from exterior walls to allow airflow

• Don’t overfill wardrobes or cupboards on outside walls — stagnant air encourages damp

Final Thought

Stopping condensation on windows is all about managing moisture and improving airflow. Start with simple habits like ventilating and wiping down windows, then look into dehumidifiers or ventilation systems for a longer-term fix. If you’re still struggling, upgrading your windows or improving insulation might be the key.