How to Stop Condensation on Windows

October 29th, 2025

Few things are as disheartening as waking up to windows streaming with water. It’s a familiar winter sight in British homes — droplets running down the glass, pooling on the sill, and sometimes even feeding black mould around the frame. Condensation may look harmless, but over time it can damage paintwork, cause wood to rot, and contribute to poor air quality.

Fortunately, condensation is one of those home issues that can be both understood and controlled. By making a few small changes to how you heat, ventilate and insulate your home, you can enjoy crystal-clear windows all year round.

Why Condensation Happens

Condensation occurs when warm, moist air meets a cold surface — and windows are the perfect example. Everyday living adds surprising amounts of moisture to indoor air: boiling a kettle, taking a shower, drying laundry, even just breathing. When this moisture-laden air cools at the windowpane, it releases water droplets onto the glass.

The problem becomes worse in colder months, when our homes are sealed up tight and windows are much colder than the air inside. Older properties, single glazing, and poor insulation make the issue more visible — but even modern, well-sealed homes can experience condensation if ventilation is lacking.

Ventilation: Your First Line of Defence

Good airflow is crucial. Without it, moisture becomes trapped, clinging to the nearest cold surface. Start by identifying where the problem is worst — bathrooms, kitchens, and bedrooms are the usual suspects.

  • Open windows briefly each day. Just 10 minutes of fresh air exchange helps balance humidity.
  • Use extractor fans effectively. Leave them running for a few minutes after cooking or showering.
  • Avoid blocking air bricks or vents. They might seem draughty, but they play a vital role in ventilation.

If condensation appears mainly at night, especially in bedrooms, slightly opening a window or trickle vent can help. For homes that feel especially damp, a dehumidifier can be a powerful ally, drawing excess moisture from the air and helping prevent the morning “soaking window” effect.

Balancing Warmth and Airflow

It’s tempting to simply turn the heating up, but warmth alone isn’t the full answer — it’s about balance. When indoor temperatures fluctuate dramatically, condensation tends to worsen.

Try to maintain a steady, gentle warmth throughout your home rather than intense bursts of heat. Cold corners and under-heated rooms act like magnets for moisture.

This is also where window coverings can quietly make a big difference. Duette® blinds, for instance, feature a unique honeycomb design that traps air within each cell, creating an insulating barrier between the room and the windowpane. This helps keep the inner surface of the glass slightly warmer, reducing the likelihood of condensation forming, while also improving overall energy efficiency.

The blinds can be adjusted to allow subtle airflow while still providing privacy and insulation.

Reduce Moisture at Its Source

Even with good airflow, you’ll want to limit the amount of moisture created in the first place. Some small adjustments can make a big difference:

  • Use lids when cooking and run the extractor fan.
  • Dry clothes outdoors when possible, or in a well-ventilated room.
  • Close bathroom doors during showers to contain steam.
  • Wipe windows and sills daily if you notice condensation as this helps prevent mould spores from developing.

You might see DIY suggestions online like leaving bowls of salt on windowsills or coating glass with washing up liquid, but these are, at best, temporary fixes. Salt can absorb some moisture, but only in very small amounts. Washing-up liquid might reduce fogging for a day or two, but it leaves streaks and doesn’t tackle the cause. The only lasting solutions are ventilation, insulation, and consistent warmth.

When Morning Windows Are Soaked

If your windows are dripping wet each morning, it’s a clear sign of trapped overnight humidity. Bedrooms are particularly prone to this, as we release moisture simply by breathing.
To help:

  • Keep bedroom doors ajar overnight.
  • Use a small dehumidifier if the air feels damp.
  • Avoid pushing furniture tight against exterior walls, as this limits air movement.
  • Consider adding insulating blinds like Duette® blinds to help stabilise window temperature.

Understanding What Condensation Tells You

Condensation isn’t necessarily a sign that your home is “too cold,” but it does mean that the air and surface temperatures are out of sync. Too much moisture, too little airflow, or uneven heating all contribute to the problem.

By tackling those three factors together, you’ll notice windows stay clearer for longer — and the entire home will feel fresher and healthier as a result.

A Drier, More Comfortable Home

Condensation is one of those subtle problems that tells a bigger story about how we live in our homes. It’s not just about dry glass — it’s about comfort, air quality, and even energy efficiency.

Through better ventilation, consistent heating, and clever insulation at the window, you can dramatically reduce condensation and the issues that come with it.

And when it comes to keeping that perfect balance of warmth and comfort, Duette® blinds offer a stylish, practical solution, helping to create a home that feels cosy in winter, cool in summer, and beautifully clear all year round.

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