A broken window seal leads to foggy panes, drafts, and higher energy bills—but how do you know if yours has failed? The most common signs include condensation between panes, a spike in heating or cooling costs, and noticeable drafts around the window.
Repairing a failed seal costs around $35 for a DIY fix or $75–$250 for professional resealing, depending on window size. In some cases, replacing the glass unit or the entire window may be more cost-effective, especially for older windows.
In this guide, I’ll explain how to detect a broken window seal, what causes them to fail, and the best repair options — including when to DIY and when to call a pro. Plus, I’ll share maintenance tips to help prevent future seal failures and keep your home energy-efficient.
- Price Range: $1,200+
- Glass and Hardware Warranty: 10–20 years
- Labor Warranty: 2 years
- BBB Rating: A+
- State Availability: 47 states
- Installs its own patented Fibrex framing
- Includes a transferable 20-year warranty on glass and a 10-year warranty on nonglass materials
- Holds an A+ rating with the Better Business Bureau
- Doesn’t carry aluminum, fiberglass, or wood frames
- Can have long wait times between consultation and installation, according to customer reviews
You can purchase the following window styles from Renewal by Andersen:
- Awning
- Bay/bow
- Casement
- Double-hung
- Picture
- Sliding/gliding
- Specialty windows with geometric shapes
This site receives compensation from the companies featured in this listing, which may impact where and how products appear. This listing doesn’t feature all companies, products, or offers that may be available.
*Costs in this article sourced from contractor estimates used by Fixr and Angi.
What Are Window Seals?
Window seals are the thin barriers between the glass panes and the window frame. Their job is to keep out dust, moisture, and outside air while helping maintain a steady indoor temperature. Good seals also improve your home’s energy efficiency by keeping warm air inside during winter and blocking heat in the summer.
How To Tell If Your Double-Pane Window Seal Is Broken
Not sure if your window seal is shot? Here are the top signs to look for:
1. Fog or Condensation Between the Panes
If your window looks foggy and you can’t wipe the condensation away, the seal is likely broken. That cloudy look means the insulating gas (usually argon or krypton) has leaked out, and moisture is getting in between the glass panes.
If you have a double-pane window moisture problem, check out our double-pane window moisture removal guide.
2. Higher Energy Bills
A sudden spike in heating or cooling costs can mean your windows aren’t insulating like they should. A broken seal lets in outside air, forcing your HVAC system to work harder.
3. Drafts Around the Window
Feeling cold air sneaking in around the window in winter? That draft may be from a broken seal — though it could also come from frame damage or worn-out window parts. Combine this with other signs to be sure.
4. Window Frame Damage or Shifting
If your window frame or window sash is cracked, warped, or tough to open, it might have shifted — putting stress on the seal and causing it to fail. But frame issues alone don’t confirm a broken seal, so check for fog or drafts, too.
What Causes a Window Seal To Break?
Most window seals fail from normal wear and tear. As temperatures rise and fall, your window glass and frame expand and contract. Over time, this constant movement puts stress on the seal, and after years of exposure, it can crack or break.
House settling can also shift the window frame just enough to break the seal. Even minor warping or bowing can cause problems because the glass doesn’t flex like the frame does.
In more serious cases, foundation problems — like cracks or water damage — can shift the structure of your home and put extra strain on your windows. If you suspect foundation issues, call a professional right away. Left unchecked, these problems can damage more than just your windows.
Different Types of Window Seals
Window seals come in a few different materials, each with pros and cons depending on your budget and window type:
- Rubber: The most common option. Durable, weatherproof, and great at blocking air and moisture. Ideal for long-term performance.
- Vinyl: Available in rigid or flexible forms. Rigid vinyl is cheaper but doesn’t last as long. Flexible vinyl holds up better over time, especially in changing weather.
- Silicone: Highly flexible and great at sealing out moisture. A solid choice if your windows face harsh weather or heavy rain.
- Foam: Often used as tape or rods to fill small gaps. Good for quick fixes or extra insulation, but not as long-lasting.
- Fiberglass Reinforced: Fiberglass cords are sometimes added to vinyl or rubber seals for extra strength, especially in high-stress areas.
The Best Ways To Repair a Broken Window Seal
Once you’ve confirmed a broken seal, there are a few ways to fix it — depending on your window’s age, condition, and your comfort with DIY work.
1. Replace the Insulated Glass Unit (IGU)
If the rest of the window is in good shape, you can swap out just the glass portion — known as the IGU — instead of replacing the whole window. This is a manageable DIY project for experienced homeowners, but it involves carefully removing the old glass and sealing in the new one without damaging the frame.
Not confident with glass work? Hiring a pro to replace the IGU is still more affordable than a full window replacement.
Read also: Windows Insulation Guide
2. Full Window Replacement
If your window is old, drafty, or part of a bigger energy efficiency issue, it may be smarter to replace the whole thing. A pro will remove the old window, check for frame damage like mold or rot, and install a new window. This is the most expensive route but it’s worth it if you’re upgrading materials or if the window is beyond repair.
3. Make a Warranty Claim
If your window is still under warranty, the manufacturer or installer may cover the repair or replacement for free. Check your paperwork — most window warranties cover seal failure for 10–20 years on glass and materials. Labor may be covered for a shorter period.
4. Have It Resealed by a Pro
In some cases, a window repair company can defog and reseal the window. They’ll remove moisture between the panes, refill the gap with insulating gas (argon or krypton), and reseal it — often in under two hours. This isn’t a DIY job, since it requires specialized tools and sealing techniques to prevent the gas from escaping.
DIY Vs. Professional Window Seal Repair
The seal around your window panes is essential for keeping your home energy-efficient. If you’re handy with home repairs, you might think about fixing a broken window seal yourself — but in most cases, it’s better to leave it to the pros. Replacing a sealed glass unit or resealing the window requires precision and the right tools. If the job isn’t done right, you could end up with drafts, water leaks, and even mold or rot around the frame — all of which are more expensive to fix down the line.
A professional can also confirm that a broken seal is your real problem and check for other hidden issues, like frame damage or moisture intrusion. Unless you’re confident in your skills and have worked with window glass before, hiring a pro saves time, money, and headaches.
Cost of a Window Seal Repair
Here’s what you can expect to pay depending on how you handle the repair:
- DIY Repair: Around $35 for basic supplies like sealant or replacement parts. Larger windows will cost more, especially if you need to replace the glass unit.
- Professional Resealing: Between $75 and $250 per window, depending on size and window type. This includes defogging and resealing by a pro.
- Full Window Replacement: On average, about $800 per window. Costs can range from $150 to over $1,000, depending on window size, style, and materials. Replacing older or custom windows typically lands at the higher end.
How To Keep Your Window Seal From Breaking
You can’t stop normal wear and tear, but a few simple steps will help your window seals last longer:
- Invest in Quality Windows: Windows from brands like Andersen, Pella, or Marvin cost more upfront but hold up better over time. Cheap windows often mean cheap seals — and more repairs.
- Re-Caulk Annually: Once a year, re-caulk the outside edge where the glass meets the frame. This helps block out moisture and reduce stress on the seal from temperature swings.
- Inspect for Damage: Check your windows yearly for cracks, drafts, or if they’re hard to open. These are signs the frame might be shifting — which puts pressure on the seal. Catching issues early can save you from bigger repairs later.
Final Verdict: Is a Window Seal Repair Worth It?
Absolutely. A broken seal means higher energy bills, drafty rooms, and a higher risk of water damage. Fixing it — whether you DIY or hire a pro — helps keep your home comfortable, protects against costly repairs, and saves money in the long run.
Letting it slide only makes the problem worse, so it’s worth tackling as soon as you spot the signs.
Frequently Asked Questions
Yes, it’s a smart move to fix a broken window seal sooner rather than later. While your window won’t collapse, a failed seal lets outdoor air and moisture seep in, driving up your heating and cooling costs and making rooms drafty or humid. Over time, that extra moisture can cause condensation between the panes and even lead to mold or water damage around the frame. If you live in an area with hot summers or cold winters, ignoring the issue will hit your wallet hard on energy bills.
Fixing a broken seal helps restore your window’s insulation power, which means lower utility bills and a more comfortable home year-round. Your HVAC system won’t have to work as hard, potentially extending its lifespan. You’ll also eliminate drafts and get rid of that cloudy, fogged-up glass that ruins your view. Sealing things up also prevents moisture damage around the window frame — a problem that can spiral into costly repairs if left unchecked.
Bottom line: Sealing the leak saves money and preserves your home’s comfort.
It can be. A failed seal not only hurts your home’s energy efficiency but may signal bigger issues like shifting window frames or structural settling. That could mean your home is letting in water, leading to rot, mold, or even hidden structural problems. Even if it’s just the seal, the added energy costs and moisture buildup are reason enough to take action. Think of it as a small fix now versus a bigger, pricier problem later.
Usually not. Insurance companies typically see seal failure as a maintenance issue, not sudden damage. Unless the seal broke due to a covered event — like a storm or fallen tree — you’ll likely be on the hook for the repair. Even if coverage applies, filing a small claim might raise your premiums, so it’s often smarter to pay out of pocket for minor fixes like this.
Most window seals last 15 to 20 years, especially on quality windows from brands like Andersen or Pella. That said, seals can wear out faster if exposed to extreme temperature swings, poor installation, or if the window isn’t maintained. Annual inspections and re-caulking the exterior can help extend the life of your seals.
