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Thermal windows, also known as double-glazed windows, have become a popular choice for homeowners and commercial buildings alike. These windows provide excellent insulation, reducing heat transfer between the interior and exterior environments. However, over time, thermal windows may develop fog or condensation between the panes, impairing their functionality and aesthetics.

In this blog, we will delve into the working of thermal windows, explore the causes of fogginess, and provide practical solutions to address this common issue.

Thermal window

Understanding Thermal Windows:

Thermal windows are constructed using two panes of glass separated by a sealed air space or filled with an insulating gas, such as argon or krypton. The space between the glass panes acts as an additional barrier against heat loss or gain, improving energy efficiency and reducing utility costs. The air or gas-filled gap minimizes heat transfer through conduction, convection, and radiation.

Working Principle:

The effectiveness of thermal windows lies in their ability to create a thermal barrier between the indoors and outdoors. The process can be explained in three steps:

Heat Absorption:

When sunlight passes through the outer pane of glass, it heats the air or gas trapped in the gap. The heat is then absorbed by the inner pane, preventing it from entering the interior space.

Thermal Insulation:

The sealed air space or insulating gas acts as an effective insulator, reducing heat transfer through conduction. This insulation prevents warm air from escaping during cold seasons and blocks exterior heat from entering during hot seasons.

Condensation Prevention:

A desiccant material, usually placed within the window frame, absorbs any moisture present in the trapped air or gas. This prevents condensation from forming on the inner surface of the outer pane.

Causes of Fogginess

Despite the efficiency of thermal windows, fog or condensation can occasionally appear between the glass panes. Some common causes include:

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Seal Failure:

Over time, the seals that hold the two panes of glass together may deteriorate due to exposure to extreme temperatures, age, or improper installation. When the seal fails, moisture-laden air can enter the space between the panes, leading to condensation.

Moisture Infiltration:

If the window frame is not adequately protected against moisture intrusion, rainwater or excessive humidity can penetrate the gap between the glass panes. This moisture can result in fog or condensation.

Thermal Stress:

Rapid temperature fluctuations or extreme temperature differentials can cause stress on the glass and the seals, leading to seal failure and subsequent fogging issues.

Solutions for Fogginess

If you notice fog or condensation between your thermal window panes, don’t worry. There are several solutions available to address this problem:

Contact the Manufacturer:

If your windows are still under warranty, reach out to the manufacturer. They may offer repair or replacement options to rectify the fogging issue.

Professional Window Restoration:

Many companies specialize in restoring foggy thermal windows. They can remove and replace the affected glass panes, reseal the window, and restore its insulating properties.

Improved Ventilation:

Enhancing ventilation within your home or building can help reduce humidity levels and minimize the chances of moisture entering the window gaps. Proper airflow helps maintain a balanced indoor environment.

Moisture Absorption:

Placing moisture-absorbing materials, such as silica gel packets or desiccant pouches, near the affected windows can help absorb excess moisture and reduce condensation.

Consider Replacement:

If the fogging issue persists or your windows are beyond repair, it might be time to consider replacing them. Newer models with advanced sealing techniques and improved materials can provide a long-lasting fog-free experience.

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Thermal windows are a valuable investment, providing energy efficiency and comfort to any space. While fogginess between the panes can be frustrating, it’s a common issue that can be resolved through various solutions. By understanding the working of thermal windows and addressing the causes of fog or condensation, you can ensure your windows remain clear, functional, and aesthetically pleasing for years to come.

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