Knowing how to fix a cracked window can help prevent small damage from turning into an even bigger problem. Even minor cracks can spread quickly, leading to larger and more costly issues or safety concerns. While you can repair some cracks with a simple do-it-yourself (DIY) fix, the size, location, and cause of the damage will determine whether a repair is enough or if you need a full window replacement.
This step-by-step guide will show you how to fix a cracked window, what causes cracks, and when to repair or replace the glass.
Key Takeaways
- You can often repair small window cracks caused by minor impacts or temperature stress with a two-part epoxy, but this approach is best suited for single-pane windows and temporary fixes.
- Cracks are typically caused by age, impact, pressure changes, or temperature differences, and identifying the cause is key to determining whether a repair will hold.
- While the repair process involves cleaning the glass, applying epoxy, and allowing it to cure, larger or recurring cracks usually require replacing the glass or the entire window.
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Pros and Cons
What We Liked
- Features proprietary window frame material that is stronger and more durable than vinyl
- Includes a transferable 20-year warranty on glass and a 10-year warranty on non-glass materials
- Provides full-service window replacement services
Keep in Mind
- Doesn’t sell aluminum, fiberglass, or wood frame windows
- Provides fewer window styles than other brands
Window Styles Offered
Renewal by Andersen offers up to eight window styles, which you can customize to fit your home’s aesthetic. Here is the full list of window styles Renewal by Andersen offers:
- Specialty
- Awning
- Bay
- Bow
- Casement
- Double-hung
- Picture
- Sliding
How To Fix a Cracked Window
Glass repair requires a few simple tools you can find at most home improvement stores. This type of repair works best for small, non-structural cracks and is typically a temporary fix rather than a permanent solution.
According to This Old House Magazine, this approach is generally limited to single-pane windows. Most modern double- or triple-pane windows require replacing the insulated glass unit rather than patching the surface.
Here’s what you need:
- Acetone glass cleaner
- Liquid dishwashing soap
- Paper plates or a cardboard surface
- Putty knife
- Rags
- Razor blade or a similar blade
- Toothpicks
- Two-part epoxy mixture
Steps To Fix a Cracked Window
Before repairing the cracked window glass, analyze the severity of the damage and identify what caused it. Fixing the crack without addressing the underlying issue can lead to the same problem happening again.
General contractor Tom Silva told This Old House Magazine that small cracks can spread quickly if left untreated, making it important to stabilize the glass and address the cause before attempting a repair.
Also, examine the length and shape of the crack. It may be time to replace the window entirely if the crack is too severe or caused by old age. There may be a different type of glass better suited for your home. If that’s the case, contacting a professional window glass replacement company is the next best step to getting the right windows.
Here are the steps involved in fixing a cracked window.
- Clean the glass: Mix a drop or two of dish soap in a bowl of water. Dip a clean cotton rag into the soapy water and carefully clean the cracked part of the glass, removing any dirt and debris. Let the glass dry.
- Mix the two-part epoxy: Next, make your two-part epoxy mixture in a well-ventilated room on a piece of cardboard or a paper plate. These mixtures are often a 50/50 blend of resin and hardener, but you should follow the directions on your specific product. Use a toothpick to mix the epoxy for at least 20 seconds. The mixture thickens and hardens fast, so once it’s mixed, be ready to use it immediately. You should have five to 10 minutes of working time before the epoxy is too thick to seep into the break in the glass.
- Apply the mixture: Apply the mixture to the cracked piece of glass with a putty knife. Do this gently to prevent further damage. Leave it to dry for about five minutes.
- Remove excess epoxy: Scrape away excess epoxy with a razor blade or another sharp blade. Next, you can use a few drops of acetone glass cleaner and a clean rag to remove the epoxy raised above the crack. Let the now-repaired glass cure for around 24 hours.
- Clean the window: Finally, spray your window with glass cleaner and polish it with a clean rag. Your window should now be as good as new.
Why Do Windows Crack?
Windows can crack for a variety of reasons, from everyday wear to sudden impact. Understanding what caused the damage can help determine whether a repair will hold or if the window is likely to fail again.
Like any home component, windows have a limited lifespan. Most windows last between 15 and 30 years, with the glass itself typically lasting around 20 years. As windows age, they become more vulnerable to pressure changes, temperature fluctuations, and general wear that can lead to cracking.
Other common causes include hard impacts, which can create starburst patterns, pressure changes from weather shifts, and temperature stress from differences between indoor and outdoor conditions.
Hard impacts, such as a rock hitting the glass, can create visible damage like starburst cracks. These cracks often spread outward from the point of impact and may worsen over time.
Pressure cracks are less common and can appear suddenly due to shifts in weather-related pressure systems. Window placement is often a contributing factor. These cracks tend to curve and spread across the entire pane.
Extreme temperature fluctuations between the inside and outside of your home can cause stress cracks. These typically start at the edge of the glass and may be small at first, but they can spread if left untreated.
Our Conclusion
Small cracks caused by minor impacts or temperature stress can often be repaired with a simple DIY fix, especially on single pane windows. However, larger cracks, recurring damage, or issues related to pressure changes may indicate a bigger problem that a patch will not solve.
A windows expert can diagnose your problem quickly and provide access to some of the best window replacement brands if you require a complete replacement. Our tool below instantly connects you with window professionals who service your address.
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FAQs About Fixing Cracked Windows
How do you cover up a cracked window?
You can cover up a cracked window with masking tape or mesh with super glue, but these solutions are only temporary fixes that halt the spread of the crack. They do not fix the crack. To completely remedy the issue, follow the steps in this guide or call a window technician.
What is the easiest way to fix a broken window?
If your entire glass pane is broken, the easiest way to replace a broken window is to remove the glass using a putty knife, clean the window, and replace that specific section of glass.
How do I know if my windows are good quality?
The quality of windows depends on how well they’re constructed. Most modern vinyl and aluminum windows are fusion-welded together, while low-quality windows may have smaller welds with caulk added to mask the crease at the sill.
To share feedback or ask a question about this article, send a note to our team at reviews@thisoldhousereviews.com.
