Windows are an essential part of a home’s comfort and energy efficiency. Over time, you might notice some windows start to look foggy, hazy, or even have condensation trapped between the panes. This common issue is often the result of a broken window seal — something homeowners should be aware of when maintaining or inspecting a property.
In this post, we’ll break down what a broken seal is, how it happens, and what you can do about it.
What is a Broken Seal on a Window?
Many modern windows, especially double-pane or triple-pane windows, are designed with insulating spaces between the panes. These spaces are filled with gas, like argon or krypton, to improve energy efficiency by reducing heat transfer. Around the perimeter of these panes is a sealed barrier that keeps the gas in and moisture out.
A broken seal means that the airtight barrier has failed. When that happens, moisture from outside air seeps into the space between the glass panes. This leads to fogging, condensation, or a hazy appearance inside the window — something you can’t wipe away from the inside or outside.
A broken seal compromises the window’s insulation performance, meaning higher energy bills and a less comfortable indoor environment.
How Do Window Seals Break?
Window seals can fail for several reasons, often developing slowly over time:
- Natural Aging: Like anything else in a home, window seals naturally deteriorate with age, especially after 10–20 years.
- Thermal Expansion and Contraction: Changes in temperature cause windows to expand and contract. Over time, this stress can weaken or crack the seal.
- Poor Installation: Improper installation of windows can put unnecessary stress on the seals, causing premature failure.
- Water Damage: If water consistently collects around a window frame due to poor drainage or flashing issues, it can wear down seals.
- UV Exposure: Sunlight can degrade the window materials and cause seals to dry out and crack.
Signs of a Broken Window Seal
If you’re wondering whether your window has a broken seal, here are the most common signs:
- Persistent fog or haze between the glass panes
- Condensation trapped inside the window, even in dry weather
- A distorted view through the window
- Noticeable drafts or a feeling of coldness around the window
- Higher energy bills despite no change in HVAC usage
- Glass panels appear warped or bulging
How Can You Fix a Broken Window Seal?
When a seal breaks, the fix isn’t as simple as wiping down the window. But you do have a few options depending on the severity and your budget:
1. Replace the Insulated Glass Unit (IGU)
- The most common and cost-effective solution is to replace just the insulated glass unit (the two panes and the spacer in between) without replacing the entire window frame.
- A professional glazier can remove the old IGU and install a new one, restoring the window’s appearance and insulating properties.
2. Full Window Replacement
- If the window is old, inefficient, or there are additional issues (like rotting frames), it may make more sense to replace the entire window.
- While more expensive, new windows offer better energy efficiency, modern designs, and often come with warranties.
3. Defogging Services (Temporary Fix)
- Some companies offer defogging by drilling tiny holes into the glass, removing moisture, and resealing the unit.
- While this can clear up the appearance, it doesn’t restore the insulating gas, so it’s often considered a temporary cosmetic fix rather than a permanent solution.
Should You Repair or Replace a Window with a Broken Seal
Whether you repair or replace depends on a few key factors:
- Age of the window: Newer windows are often worth repairing.
- Extent of the damage: If multiple seals are broken, full replacement may be more economical.
- Energy efficiency goals: Homeowners focused on energy savings often opt for window upgrades.
- Budget: Repairs can be significantly cheaper than full replacements but may not offer long-term efficiency gains.
If you’re preparing to buy or sell a home, a broken seal might also come up during a home inspection — and it’s important to address it. While a single broken seal is not usually a structural concern, it can affect appraisal value, energy ratings, and buyer perception.
Final Thoughts
A broken window seal is a common but manageable issue. Left untreated, it can lead to increased energy costs and a less comfortable home environment. Fortunately, solutions are available, from simple glass unit replacements to full window upgrades.
At Nordic Inspections, we take window condition seriously as part of every home inspection. If you’re concerned about window seals or overall window health in a property, we’re here to help you spot issues before they turn into bigger problems.
Questions about your home inspection or window issues? Contact us today!