Why Window Seals Fail and How to Fix Them

Window seals are crucial for maintaining the efficiency of your home, and their failure is a common issue that homeowners face. Understanding why window seals fail and knowing how to fix them can prevent unnecessary window replacements and keep your home energy efficient.

The primary cause of window failure is seal failure. But what exactly leads to this, how can you prevent it, and how do you recognize the signs of seal failure in your home? These are essential questions for maintaining the integrity and efficiency of your windows.

A window installer applying window sealant

What Is Seal Failure?

Seal failure is when the caulking or weather stripping around the window frame begins to peel up, crack, or break off.

A window protects your home from outside elements like wind, rain, and solar heat. If the seal around the window fails, you risk damaging the interior of your home and its internal frame and decreasing your home’s energy efficiency.

When Does Seal Failure Occur?

Seal failure occurs when the caulk is not applied properly around the window or a cheap or wrong one is used.

If you notice a breeze coming through or that your windows are fogging up, chances are you need someone to come out and repair or completely replace your windows!

Check out this video on our Facebook page to see what a window sealant failure looks like.

Do Windows with Broken Seals Need to Be Replaced?

Whether windows with broken seals need to be replaced depends on the extent of the damage and your energy efficiency needs. A broken seal can lead to condensation forming between the panes of glass.

In some cases, if the window is still structurally sound and the visual impairment is minimal, you can leave it as is, especially in less critical areas of your home. However, for most homes, especially in climates with temperatures that fluctuate a lot, replacing the window might be necessary to maintain energy efficiency and comfort.

Rot on wood frame because of window sealant failure

Types Of Window Sealers

The types of window sealers available on the market vary greatly in terms of characteristics, cost and efficacy. From polyurethane foam to butyl rubber and silicone, there are a number of choices when it comes to sealing windows and doors.

Polyurethane Foam

Polyurethane foam is among the most popular types of window sealers because of its low cost and ability to expand and contract with changes in temperature, thereby providing a snug fit against weather elements.

Butyl Rubber

Butyl rubber is an effective sealant that is also resistant to prolonged heat and sunlight exposure, making it highly reliable for outdoor use.

Silicone-Based Sealants

Silicone-based sealants are best for indoor applications as they won’t corrode the window frame but won’t provide long-term insulation either.

How to Fix a Broken Window Seal

Repairing a broken window seal typically involves replacing the pane or the entire window, as resealing effectively is challenging. Evaluate the extent of condensation or fogging and consult a window repair specialist for the best approach. If the frame is intact, you might only need to replace the glass panes. 

However, for older windows or damaged frames, replacing the entire window might be more cost-effective. Consider upgrading to windows with advanced insulating technologies like double or triple-pane glass for improved energy efficiency.

Regular maintenance can help extend the life of new or repaired windows and enhance your home’s energy performance.

Best Window Sealer Brands

1. Sashco

Sascho has been making top-notch window sealers for over 100 years, ranging from caulks and sealants to weatherstrips and glazing compounds. Their products are designed to ensure long-lasting durability and optimum performance in all climates and weather conditions. The company’s signature product is the Big Stretch Caulk, which is an acrylic latex sealant designed to expand and contract with changes in temperature.

2. Loctite

Loctite makes a wide range of sealants for windows, including butyl rubber sealants, silicone-based caulks, and weatherstripping compounds. Their products are specifically designed to provide lasting protection against weathering elements and offer superior adhesion and flexibility.

3. DAP

DAP offers various window sealers, including acrylic latex caulk, silicone-based sealants, and weatherstripping compounds. Their products are designed to provide long-lasting protection against the elements while offering excellent adhesion and flexibility.

4. Red Devil

Red Devil makes a complete line of window sealers and caulks, ranging from latex acrylic to silicone-based compounds. Their products are designed to ensure long-lasting performance in various weather conditions while offering superior adhesion and flexibility.

5. Sika

Sika makes a wide range of window sealers, including butyl rubber sealants, silicone-based caulk, and weatherstripping compounds. Their products are designed to provide superior protection against weathering elements and offer excellent adhesion and flexibility.

Who Should Install Your New Windows

When it comes to installing windows, it is important to have a professional do the job.

A professional window installer has the knowledge, experience, and tools necessary to install windows properly and ensure they are sealed properly to protect against weather elements. Professional installers will also be able to identify any potential flaws or issues with your windows before they are installed and make the necessary repairs.

When choosing a window installer, it’s important to look for someone reliable and trustworthy. You should also ask for references from past customers or check out their reviews online before hiring them.

One great way to research contractors is to check the local Chamber Of Commerce in Gallatin, TN, or Gallatin’s BBB website.


Sealant failure compromises your home’s efficiency and comfort, so taking immediate action after you observe your windows are in a bad condition is crucial.

Leave them as is and you’ll see a rapid increase in your heating bills.

If you’re ready to work with a professional window installer that can guarantee your windows will be fully functional and efficient, give us a call at (615) 861-2315 or request your free quote now!