How to Deal with Condensation on Windows

Are your windows fogging up when it gets cold outside? That might seem normal, but persistent condensation can lead to mold, water damage, and even higher energy bills.

In this guide, we’ll break down why condensation happens, how to prevent it, and why upgrading to energy-efficient windows could be your best long-term solution.

What Causes Condensation on Windows?

Condensation on windows occurs when warm, moist air comes into contact with a cooler surface, leading to the formation of water droplets on the glass.

There are different types of window condensation:

• Interior condensation: This is the most common and is caused by excess indoor humidity. It usually happens in winter when warm air inside meets cold window glass.
• Exterior condensation: Occurs when humid outdoor air contacts a cooler exterior window surface. This is usually harmless and means your windows are doing their job.
• Between-pane condensation: If you notice fog between double- or triple-glazed windows, it likely means the window’s seal has failed. This usually requires window replacement.

Factors Contributing to Window Condensation

This phenomenon is influenced by several factors:

• Indoor humidity levels: Everyday activities such as cooking, showering, and even breathing release moisture into the air. When indoor humidity is high, especially during colder months, excess moisture is more likely to condense on cooler surfaces like windows.
• Temperature differences: Condensation is more likely to occur when there is a significant temperature difference between the inside and outside of a home. Warm indoor air can hold more moisture, and when it comes into contact with cold window surfaces, the air cools rapidly, releasing moisture in the form of condensation.
• Window insulation and glazing: Windows with poor insulation or single-pane glazing are more prone to condensation. Modern double or triple-glazed windows provide better thermal performance, reducing the likelihood of condensation by keeping the interior glass surface warmer.
• Ventilation: Inadequate ventilation can trap moist air inside, increasing indoor humidity levels. Homes that are well-sealed for energy efficiency may inadvertently reduce natural airflow, leading to higher chances of condensation on windows.
• Seasonal changes: During winter, the combination of heated indoor air and cold external temperatures creates ideal conditions for condensation. Conversely, in warmer months, air conditioning can cool indoor air, potentially leading to condensation if indoor humidity is not managed.

How to Fix Existing Condensation Issues

If condensation is already forming on your windows, there are a few ways to address the problem before it leads to mold or water damage.

Reduce Indoor Humidity

• Use dehumidifiers: Deploy dehumidifiers in areas prone to high moisture, such as basements and bathrooms, to extract excess humidity from the air.
• Run exhaust fans: Ensure that kitchen and bathroom exhaust fans are used during activities that generate moisture, like cooking and showering, to expel humid air outside.
• Monitor humidity levels: Aim to maintain indoor humidity between 30-50%. Hygrometers can help monitor these levels, allowing for timely adjustments.

Enhance Ventilation

• Open windows periodically: Even during colder months, briefly opening windows can allow moist air to escape and fresh air to circulate, reducing indoor humidity.
• Utilize ceiling fans: Ceiling fans can help distribute air evenly, preventing pockets of moisture-laden air from settling on window surfaces.

Upgrade Window Insulation

If your windows are old or single-pane, upgrading to double or triple-glazed windows with low-emissivity (Low-E) coatings can significantly reduce condensation by enhancing thermal performance.

Regular Maintenance

• Seal leaks and gaps: Inspect windows for any gaps or deteriorated seals that may allow cold air infiltration, exacerbating condensation issues.
• Clean window surfaces: Regularly clean windows to prevent mold growth resulting from persistent condensation.

If your windows are outdated, poorly insulated, or constantly covered in condensation, upgrading to modern energy-efficient windows could be the best long-term solution.

How to Prevent Window Condensation

There are several ways to prevent window condensation before it becomes a bigger issue.

Control Indoor Humidity

The best way to stop condensation is to lower indoor humidity levels. Use a dehumidifier, run exhaust fans in the kitchen and bathroom, and open windows for fresh air circulation when possible.

Improve Air Circulation

Ceiling fans and HVAC systems help distribute air evenly, reducing moisture buildup in certain areas. Even something as simple as leaving doors between rooms open can help with airflow.

Maintain a Consistent Temperature

Frequent temperature fluctuations can lead to condensation. Keep your thermostat at a steady temperature to prevent window glass from getting too cold.

Adjust Window Treatments

Heavy curtains and blinds can trap moisture near windows. Keeping them slightly open allows air to circulate, reducing condensation buildup.

How Energy-Efficient Windows Can Reduce Condensation

If you’re considering a window replacement, choosing energy-efficient models can make a significant difference in preventing condensation.

Modern energy-efficient windows with double or triple glazing provide better insulation, reducing temperature differences between the indoor air and the glass surface. This helps minimize the conditions that cause condensation to form in the first place.

GEALAN offers advanced window systems designed to improve insulation and prevent condensation buildup. With innovative multi-chambered frames and precision-engineered seals, our windows help keep moisture out while enhancing energy efficiency.