Condensation on the roof window: Everything you need to know!

Waking up to droplets of water on your roof windows is a common sight, especially on cold winter mornings. This condensation, formed on the inside of roof windows, isn't just an aesthetic issue—it can lead to serious damage to your home. While condensation may also appear on the outside, much like rain, this article focuses on the internal condensation that can be problematic. Why does it occur inside your roof windows, and how can you prevent it? Our experts are here to help you keep condensation in check!

Condensation happens when warm, moist air meets a cold surface—in this case, your roof windows. Roof windows, especially older models, can act as cold bridges, where heat escapes from inside your home, causing temperature differences between the window pane and the indoor air. When warm air cools upon contact with the cold window pane, it releases moisture, forming water droplets. This is why condensation forms on the inside of your roof windows.

While occasional condensation is normal, regular or heavy condensation can be a sign of a deeper issue. Some common causes include:

• Poor insulation: Older roof windows often lack proper insulation, allowing significant temperature fluctuations between indoors and outdoors. In winter, this can lead to condensation buildup on the colder window surfaces.
• High indoor humidity: Daily activities like cooking, showering, and drying clothes release moisture into the air, increasing humidity levels. In a household of three, up to 10 liters of water can evaporate into the air within 24 hours.
• Inadequate ventilation: Without proper ventilation, humid air stays trapped inside your home, promoting condensation and even mold growth.

Condensation on your roof windows isn't just an annoyance—it can cause serious damage over time.

• Mold growth: Persistent moisture creates the perfect environment for mold to thrive, especially on window frames and seals. Over time, mold can spread to walls and other surfaces, compromising both your health and your home’s structure.
• Damage to window seals and frames: Prolonged exposure to moisture can weaken window seals, leading to leaks and further damage. Preventing condensation early can save you from costly repairs down the line.

Don’t worry—there are simple ways to prevent roof window condensation and improve your indoor climate:

1. Ventilate Regularly
   Proper ventilation is crucial. Aim to ventilate at least twice a day for 8 minutes, preferably in the morning and evening. If you notice condensation on your roof windows, increase the frequency and create a cross-breeze to quickly reduce moisture levels.

Tip: Learn more about how to ventilate properly with our guide on Ventilation Tips by Roto.

        2. Maintain an Even Room Temperature

Keeping your room temperature steady prevents cold spots that encourage condensation. Ensure the temperature stays above 21°C, and make sure that radiators or curtains aren't obstructing airflow.

       3. Minimize Moisture Sources

Use outdoor spaces like your garden or balcony to dry laundry. When cooking, use an extractor fan or simply open a window. After showering, make sure to ventilate thoroughly to lower humidity quickly.

      4. Choose the Right Houseplants
Plants like ivy or peace lilies can help absorb excess moisture, but be careful—potted plants can become a source of moisture if overwatered. Make sure to choose the right plants for your indoor environment.

      5. Install External Roller Shutters
Roller shutters can provide additional insulation, reducing condensation on your roof windows. They also offer protection from the elements, heat, and even potential break-ins.

Tip: Learn more about Roto external roller shutters and their benefits.

     6. Check Your Insulation
If you have older roof windows, upgrading to modern, energy-efficient models can drastically reduce condensation. Well-insulated windows prevent heat loss, keeping your indoor climate stable and moisture levels under control.

    7. Regular Window Maintenance
Proper roof window care is essential for preventing damage caused by condensation. Learn how to maintain your Roto roof windows with our comprehensive guide on roof window care and maintenance.

Roof window condensation is an issue that shouldn’t be ignored. However, with the right steps, you can eliminate condensation and enjoy a healthier indoor climate. Regular ventilation, managing humidity, and investing in insulation upgrades are key to keeping your home moisture-free. With these expert tips, you're well on your way to protecting your roof windows and ensuring a comfortable living environment.