Understanding the Underlying Causes of Window Seal Failures

Windows provide more than just a view; they’re a crucial barrier against external elements. Window seals ensure energy efficiency and prevent moisture intrusion, and their failure can lead to increased humidity and other consequences. Here, we examine what window seals are, why they’re important to the window’s integrity, and why it’s important to consider them during a claims assessment.

Many variables should be considered when assessing a compromised window seal, which may lead to fogging or other condensation between panes.

What Are Window Seals?

Window seals are present in modern double- and triple-pane windows. They aren’t to be confused with sealant, which is a material applied around the window frame, exterior, and sill to seal these exterior claddings and help prevent leaks. On the other hand, seals are material applied between panes of glass to keep the gas, like argon, that separates them from escaping and outside elements like moisture from penetrating.

Why Window Seals Fail

Windows seals may fail for a few reasons, including:

• Age-related or accelerated deterioration
• Manufacturing defects
• Shipping damage
• Improper installation
• Extreme weather, such as wind

Age-related deterioration is the most common cause of loss determined during window damage inspections. Even well-maintained windows age, and that process may be accelerated by any of the factors listed above. Several factors, including quality, impact the life expectancy of windows; however, seal failures may still occur sooner. In rare cases when conditions allow, a strong enough wind may displace the window unit elements, which can detach the seal. 

An expert indicates a displaced seal, which signifies that the space between the windowpanes is vulnerable to moisture infiltration.

Common Results of Seal Failure

As a window ages, its seal becomes less effective at keeping out external elements like dirt and moisture. In some cases, a window with a failed seal may look dirty despite having been cleaned because the particles have gotten between the panes.

The overwhelmingly common result of seal failure is fogging, a condition in which moisture in the surrounding air infiltrates between the panes. Trapped air then undergoes cyclic thermal expansion and contraction, meaning it’s heated by sunlight and cooled by things like rain or sundown. The unsealed window draws humid air in, fogging the glass. Unchecked, this may lead to water damage, mold growth, and staining.

Investigating Failed Window Seals

A claim that involves fogging or other potential seal-related damages should be assessed by an expert familiar with windows and their failure modes. There may be associated losses to the structural window elements and surrounding structure depending on the reason for the seal failure. Because age-related deterioration is a common cause of loss, a settlement decision should factor in the window’s age and manufacturer, historical weather data and surrounding collateral indicators, and other on-site evidence.

Donan’s forensic engineers deliver practical insights by thoroughly analyzing window units and their associated damages or failures. Submit an assignment to feel confident in your window claims resolutions.

Alpine Intel’s content is meant to inform and educate readers using general terms and descriptions. They do not replace expert evaluations that determine facts and details related to each unique claim.