The 5 Best Caulk for Sealing Window Glass in 2023: Become an Expert Window Caulking Pro

Last Updated on October 2, 2023

Shield your windows from the elements and combat annoyances like pests and water damage with a solution you can count on. Professional weatherproofing starts with quality caulking to ensure long-term protection against pest damage, draftiness, and water intrusion.

For a perfectly sealed window resistant to wear and tear, we have researched the best caulks for sealing window glass from a selection of trusted brands. Seek out the best caulk for sealing window glass that will provide extreme durability, weather resistance, and unmatched protection for your windows.

Let’s pick the best window glass sealant for your project and see how it seals glass from water damage.

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The 5 Best Caulks for Sealing Window Glass: Our Top Picks to Keep Your Home Protected

When sealing your window glass, you have many options and choices. Each type of caulking material has different benefits based on the job that needs to be done.

The following are our top 5 recommendations for window glass sealing caulk in 2023 for you to consider when shopping around: Let’s take a look at the advantages each of these caulks offers and understand why they are our top picks.

1. Gorilla Waterproof Caulk & Seal 100% Silicone Sealant: The Best Weatherproofing Caulk for a Tight Seal

Are you looking to invest in a top-notch, long-term weatherproofing solution for your windows and doors? Gorilla 100 Percent Silicone Sealant Caulk offers supreme protection against water, air, and moisture. 

This sealant won’t crack or shrink over time, and you’ll enjoy superior UV resistance and a waterproof seal that will hold up against extreme weather.

Let’s see what makes this one of our top picks.

An Impenetrable Waterproof Barrier

Gorilla 100 percent silicone sealant caulk is the gold standard in waterproofing protection. It provides an impenetrable barrier against water, air, and moisture.

The caulk meets ASTM C-920 specifications for class 50 using G,A for the elasticity and adhesion of sealants. It is made with a low VOC content which means it can be used in most areas without worry.

Flexible Weatherproofing

This high-performance silicone sealant is perfect for indoor and outdoor use because it is all-weatherproof. It is designed to stay permanently flexible, expanding and contracting with weather temperature fluctuations to fill gaps around windows without cracking or shrinking over time.

UV Resistant

This sealant offers excellent UV resistance so that it won’t fade or discolor after prolonged exposure to sunlight. 

Quick Drying Time

The fast-drying formula dries in as little as 30 minutes so that you can move on to the next project quickly. This formula is also paintable, so you can customize it to match the color of your window frames or sills.

Easy Application

Easy to Apply and Clean Using the Gorilla Waterproof Silicone Sealant is easy, and finger tooling works well. The tip can be unscrewed and cleaned for storage, and a plastic sheet can be used to cover the opening. While it requires a day to cure, it provides a highly waterproof seal that lasts for years.

Mold & Mildew Resistance

All Gorilla Waterproof Caulk & Seal products come with built-in mold and mildew resistance, so you don’t have to worry about harmful growth in your home. This is especially helpful if you live in a wet or humid climate where mold spores are prone to forming quickly. 

The sealant provides an extra layer of protection against these dangerous pollutants that could cause damage to the structure of your home over time.

Versatile Uses

It can be used on various surfaces, from glass to concrete to drywall, making it an excellent choice for a range of projects around the home. Whether you need to fill gaps in walls or create an airtight seal on windows and doors, you can count on this waterproof sealant.

Long Lasting Protection

With its unique formula designed for long-lasting protection, it will remain flexible and won’t degrade over time due to UV exposure or extreme weather conditions. This means that once you apply it onto a surface, you don’t have to worry about reapplying it anytime soon.

Negative Reviews are Due to User Errors

Negative reviews regarding the difficulty of use are typically due to not removing the foil from the tube or not using a caulk gun. Following the instructions and using a caulk gun make the product easy to use.

2. Red Devil Lifetime Ultra 230 Acrylic Latex Window Sealant: Create an Impenetrable Barrier Against The Elements

Red Devil’s Lifetime Ultra 230 Acrylic Latex Window Sealant is a product steeped in history and crafted with quality, dependability, and innovation in mind. For over 150 years, this sealant has been the choice of professional contractors and do-it-yourselfers for its superior performance and unparalleled durability.

Tough & Weatherproof

This premium latex-based window sealant is designed to stand the test of time and provide lasting protection against water infiltration and air leakage. Formulated with advanced acrylic components, it creates an impenetrable layer that defends against dust, wind, pollutants, and extreme temperatures.

A High Level of Adhesion

The high-tack formula offers superior adhesion to virtually any surface, including wood, metal, brick, concrete, and other masonry materials. The sealant’s special adhesion properties help ensure your project will withstand the elements without shrinking or cracking over time.

And with its lifetime durability is no exception, boasting superior strength for any job you throw at it.

Quality

Red Devil is renowned for their commitment to quality, dependability, and innovation in the professional contractor and do-it-yourselfer markets, providing the latest easy-to-use tools that guarantee superior results every time.

Paintability

If you want to add some extra style to your project after applying Red Devil Sealant, there’s no need to worry. This product boasts excellent paintability allowing you to spruce up walls, furniture, door moldings, cabinets, sinks, tubs, window frames, and much more with ease.

Easy Application

Red Devil Sealant is easy to use, requiring just a few simple steps. Simply apply the sealant with a caulking gun and smooth it out with a damp cloth or paper towel if needed.

Versatility

This versatile sealant is perfect for interior and exterior jobs, making it an essential tool in any do-it-yourselfer’s arsenal. Whether you’re looking to weatherproof windows and doors or seal off cracks and gaps around your home, Red Devil Sealant has covered you.

3. GE Window & Door All Purpose Clear Sealant: Guard, Shield, and Seal Your Window Glass at the Most Affordable Price

GE All Purpose Window and Door Silicone Sealant is the perfect choice for unbeatable protection against the harshest outdoor conditions.

With its advanced 100% silicone formula and highly durable blend of materials, this reliable shield guarantees long-term defense against nature’s most damaging elements to safeguard your investments with confidence.

Meets ASTM C-920 Class 25 Requirements

ASTM C-920 Class 25 rated, this product ensures a perfect seal against moisture and air infiltration in residential and commercial applications. It is designed to remain flexible in temperatures up to -40°F making it ideal for cold climates.

100% Waterproof & Versatile

This 100% silicone sealant is 100% waterproof and weatherproof, an ideal solution for projects that need to stand up to harsh weather conditions and won’t shrink, crack, freeze, or be affected by sunlight. 

It’s great for interior and exterior applications like windows, doors, siding, trim, molding, baseboards, and vents. You can even use it to seal wires and pipes.

Same-Day Rain-Ready Formula and Fast-Curing Time

This fast-curing sealant is perfect for ensuring your windows and doors are watertight. It won’t yellow or crack over time and will be rain-ready in as little as 12 hours after application. 

Flexible & Strong Adhesion

GE All Purpose Window and Door Silicone offers superior flexibility while remaining strong when fully cured. This means that no matter what kind of job you have, big or small, this sealant will hold up its end of the bargain without fail.

Easy To Use & Clean Up

Working with GE All Purpose Window and Door Silicone is easy, simply apply it using a caulking gun and smooth out any excess with a damp cloth or paper towel if needed. When you’re done with your project, cleanup is just as simple; remove any remaining sealant residue with soap and water before it hardens completely.

Safety

While safety should always be a top priority on any DIY project, there’s no need to worry about using this silicone sealant. It is certified non-toxic, so you don’t have to worry about nasty fumes or unpleasant odors that other adhesives might have.

4. Frost King Indoor & Outdoor B2 Mortite Caulking Cord and Weatherstrip: A Pro-seal and Best DIY Choice

The Mortite Caulking Cord has been the go-to product for decades and is still famous for its quality and versatility. It is designed to seal cracks around windows, doors, and other frames indoors and outdoors.

The cord is made from a blend of cotton, rubber, and asphalt, creating a superior seal that won’t crack or tear over time. The ease of use and its versatile applications make this an ideal choice if you’re looking to save money by tackling window weatherization yourself. 

Superior Adhesion

This unique product is made from a strong and durable blend of cotton, rubber, and asphalt. This blend makes the cord highly flexible, making it easier to work with in tight spaces and providing a superior seal that won’t crack or tear over time.

Best DIY Choice

As mentioned before, this product is perfect for DIYers looking to save money. An affordable option compared to other products, this cord is easy to install and can be used on both indoor and outdoor frames.

Also, to buy it in bulk for even more savings, you’ll be pleased with how effectively this product works, giving you great value for money spent.

Versatility

It will seal windows and be used as gasketing material, sound deadener, insect barrier, crack filler, and all-around plugger-upper. It is easy to adjust and remove if necessary and provides a strong seal that won’t crack or tear over time.

Long-Term Adhesion 

The caulking cord offers superior adhesion, so you don’t need frequent reapplication or leaks.

Insulation Benefits 

Keep air drafts out of your home, thus insulating your windows against outside temperatures. This means you can save energy costs in the long run.

Fills Cracks and Stops Drafts 

It fills any gaps effectively so that you won’t have to worry about cold air or bugs coming through any cracks when using. You can keep your home warm in the winter months without having to turn up the heat too much or pay extra money on heating bills.

5. Dap Alex Plus Acrylic Latex Caulk Plus Silicone for Window Weatherization: Seal With Superior Strength and Flexibility

A brilliant solution for window weatherization and sealing with superior strength and flexibility. This top-of-the-line premium caulk features a 35-year durability guarantee and exceeds ASTM Specification C 834.

Perfect for indoor and outdoor usage, it offers superior adhesion, enhanced flexibility, and long-lasting protection against water penetration. Whether you’re looking to fix gaps in your siding, around windows and doors, or in any other area requiring a tight seal and extra protection from the elements, Dap 18128 Alex Plus makes a perfect choice.

Long-lasting Waterproof Seal

With an impenetrable layer that defends against dust, wind, pollutants, and extreme temperatures, this outstanding sealant is ready to tackle any weatherproofing job. Its superior adhesion allows it to form a long-lasting waterproof seal that will keep out moisture and drafts.

Flexibility & Durability

Enjoy superior flexibility and durability when using Alex Plus Acrylic Latex Caulk Plus Silicone. This outstanding caulk offers an impressive range of motion which allows it to move with temperature changes to form a tight, long-lasting seal. Its high-strength formulation ensures a reliable bond between surfaces, even in extreme conditions. 

Adhesion & Paintability

Alex Plus Acrylic Latex Caulk Plus Silicone has a strong multi-surface adhesion that won’t be easily broken down by moisture or other environmental factors that could cause common caulking products to fail. It can also be painted over after just 30 minutes of drying, allowing you to match your project perfectly with any color you desire.

Mold & Mildew Resistant

It also protects against mold and mildew growth to help protect your home from potential health risks associated with these dangerous fungi without requiring additional products or treatments. The advanced formula provides added protection against humidity so that you can rest assured that your project remains safe and sound.

ASTM Specification Compliance

All of the ingredients used in Alex Plus have been tested and certified by ASTM International as meeting their stringent standards for safety, quality, performance, and compliance with relevant regulations across all industries they cover, giving you confidence in the product’s reliability from start to finish.

What to Look for When Choosing the Right Caulk for Sealing Window Glass?

When selecting window glass sealants, there are many factors to consider. Each type of caulk has different advantages and disadvantages depending on what kind of application it is being used for.

Here’s a quick guide to help you understand exactly what to look for and how to choose the right product to protect your windows from weather, pests, and more.

Material of the Caulk

This is probably the most important factor to consider when choosing a caulk for window glass. You need to choose one compatible with the materials it will be used on.

For example, brick and masonry need a caulk that has a strong adhesive bond and is designed for exterior use. Wood must have a paintable caulk that won’t crack or peel when exposed to moisture; aluminum or vinyl window frames will need a high-grade silicone caulk that can handle extreme temperatures and UV rays.

It’s also important to note that some materials, such as glass, may require specialty caulks with extra adhesion qualities to get a strong bond. If you have windows made from vinyl, aluminum, or any other metal alloy, you should look for a water-based acrylic caulk specifically designed for these materials.

Silicone-based caulks are often recommended for wood frame windows since they provide superior adhesion and are more resistant to cracking and shrinking. 

Consider Exterior Conditions

Caulk used on windows should be able to stand up against moisture and sunlight without cracking or fading over time. Suppose you live in an area with drastic temperature changes throughout the year. In that case, it’s important to pick out a caulk that can flex without cracking or breaking down under pressure from expanding and shrinking due to extreme temperatures.

A high-grade silicone caulk is your best bet here; it was specifically designed for exteriors and can withstand even the most extreme temperature fluctuations without deteriorating over time. The best type of caulk for this purpose is an exterior-grade silicone caulk with mildew-inhibiting ingredients or ultraviolet protection additives that prevent damage caused by ultraviolet rays from the sun.

Choose a waterproof sealant that won’t crack over time due to extreme temperature swings or water damage. Silicone-based caulks and polyurethane caulks are often preferred because they offer greater flexibility and last longer than other types of caulk. 

Window Pane Type

Different types of glass require different types of caulks. Tempered glass, for instance, should be sealed with a silicone caulk designed to withstand extreme temperatures and UV rays.

Laminated safety glass requires a unique adhesive or sealant specifically made for this type of window pane to ensure a secure bond without compromising its strength or integrity.

Finally, insulated dual-paned windows require a special high-grade sealant to ensure a secure seal between the two panes of glass. This type of caulk should be able to withstand extreme temperatures without cracking or deteriorating over time. 

Understanding Crack Size

The size of the space you need to fill also determines what kind of caulk you should use for your windows. If you’re dealing with very small cracks and gaps, then a standard latex caulk should suffice.

But, if you’re dealing with larger gaps (such as those found around window frames), it’s best to use something like an exterior-grade silicone caulk. Which has more flexibility than other caulks and provides better adhesion when filling large voids between materials.

You might also need to purchase additional supplies, such as plastic corner guards or backer rods, to help create an even shape before applying the caulk itself if the gap is particularly large. 

Paintability

For aesthetic purposes, many prefer painting over their caulking job to match their window frame color. This is especially common when working on old wooden windows where wearing paint jobs is commonplace. 

In this case, it’s important to choose a latex-based caulk that allows for easy painting over with water-based paints after curing. Latex-based caulks also tend to contract less than others when drying, making them less prone to cracking from drastic temperature changes.

Curing Time

You should also consider the curing time of your caulk before deciding which one to use. Latex and acrylic caulk generally require 24 hours to cure before painting or exposing them to water. However, silicone-based caulks can sometimes take up to 72 hours before they are fully cured.

Some types of silicone-based caulk may also take longer and may even require up to a week before they are completely set. Make sure you check the caulk’s label for curing times before application.

Ease of Use

It is important to consider how easy it is to use when selecting a window sealant for your home renovation project. Some products come pre-mixed in cartridges, while others are sold in tubs that require some mixing before use.

Look for products that are easy to apply, with a uniform consistency and smooth finish, for the best results.

Look for low-odor and low VOCs

VOCs refer to volatile organic compounds that have the potential to cause harmful health effects when inhaled or absorbed through skin contact. Low-odor caulks should have little to no smell when applied and can make working around them much more comfortable.

Similarly, low VOCs reduce the risk of breathing in toxins from the caulk itself. 

Read Reviews

Reading customer reviews can help you get an idea of how well different products perform in real-life scenarios, especially regarding durability, application comfortability, and overall satisfaction with their purchase experience the product.

Then you can learn what caulk works best for your specific needs and expectations based on quality assurance and cost efficiency before you make your own decision.

These are some of the most important factors you should consider when selecting a window sealant for your home renovation project. The right caulk can make a huge difference in protecting your windows from water damage and temperature changes while also providing an aesthetic appeal.

Researching the various caulks and reading reviews can help you make a well-informed purchase decision and ensure that your windows are properly sealed for years to come.

How Do You Properly Caulk a Window?

Caulking a window is an essential step in creating a tight, air-proof seal. To do it properly, you’ll need first to ensure that the area around the frames of your windows is clean and free from any dust, dirt, or grease.

After this is done, you can begin to apply the caulk. Start by selecting a quality caulk for your specific needs and read the instructions and warnings on the packaging carefully.

Once you have chosen a product, cut the tip of the tube to create an opening that is slightly larger than the width of the gap or crack. Then, using either a caulking gun or a putty knife, apply the caulk in a continuous bead to the area that you are sealing.

Finally, smooth out the caulk with your finger or a damp sponge and allow it to set before painting over it if necessary.

After finishing caulking your windows, you can use painter’s tape to cover up any excess caulk before painting over it with paint that matches your windows’ frame color. With these steps followed correctly, you should be able to achieve perfectly sealed windows and protect them against drafts or moisture.

Caulking Your Windows: Common Mistakes to Avoid

To ensure a quality seal, it’s important to avoid some of the most common mistakes people make when caulking around windows:

Not Preparing the Surface Adequately

Before you apply any caulk or sealant, it’s critical that you prepare the area around your windows. This includes removing any old sealant or putty, as well as cleaning away dirt and debris. If not done correctly, this can prevent the new sealant from adhering properly, leaving gaps where air could infiltrate. 

Making the Wrong Choice of Sealant

Choosing a suitable sealant around your windows is essential for achieving a quality result. A high-grade silicon-based sealant is often best for these applications due to its flexibility and ability to stretch with any movement of the window frame over time. 

Incorrect Caulking Gun Use

You must use an appropriate caulking gun to apply sealants or caulk around your windows; otherwise, you may not get a proper bead or “line” of caulk along your window frames. Caulk guns are designed with different nozzle sizes that dispense different amounts of the product depending on what material you’re working with; be sure to choose one that fits your needs! 

Over- or Under-application of Sealants

Applying too little caulk won’t provide enough coverage and may lead to air leakage. At the same time, over-applying can create an unattractive mess and cause difficulty when trying to smooth out the material afterward. 

When doing caulking work around windows, try using just enough material until you have a consistent line along each edge of the frame without overfilling it with excess product.

Leaving the Sealant Unshaped after Application

After applying caulk or a sealant around your window frames, it’s important that you use a wet finger or tool (such as a plastic spatula) to shape and smooth out the material into a continuous line before allowing it time to dry completely. Otherwise, you may not achieve proper adhesion between surfaces or create unsightly ridges along edges where air may leak through.

For best results, always try shaping/smoothing out newly applied materials immediately after application so that everything looks neat and tidy once dried up. 

Maintenance is Key

Once you have selected the appropriate caulk and applied it properly, don’t forget that regular maintenance is key to keeping your windows sealed and in good condition.

Once your window glass sealant has been applied, it’s important to check it regularly throughout the year for any signs of wear and tear or cracking caused by weather conditions or age.

Make sure to clean off any mildew or dirt buildup with a damp cloth before reapplying more caulking if necessary, this will keep your windows looking great and protect them from further damage down the road.

Is Silicone Caulk Compatible with Glass?

Silicone caulk can stick to glass. Silicone caulk is a sealant designed to bond with many different materials, including glass.

It creates a strong, water-resistant bond between the two surfaces, making it ideal for sealing cracks and gaps in glass windows or doors. To ensure the best results, it’s important to clean the glass surface thoroughly before applying the silicone caulk.

If there is any dirt or dust present on the surface of the glass, it can prevent the caulk from adhering properly and create weak spots in your seal. And be sure to choose a silicone caulk designed for the type of glass you seal.

Some types of silicone caulk may not adhere well to certain types of glass, so always check the label before use.

Upgrade Your Windows and Protect Your Home with the Best Window Sealants on the Market

Sealing windows with caulk is essential in keeping your home energy efficient and protecting against costly damage. It’s important to research the different types of caulks available on the market before purchasing since each one offers its own advantages and drawbacks.

The Gorilla brand window sealant provides an excellent combination of quality and affordability, while the Red Devil brand is a more premium option for those seeking a higher-end product. Both are durable and easy to apply, ensuring the long-term use of your windows with minimal effort.

With the right caulk, you can give your windows a powerful seal that lasts for years. Armed with proper care and maintenance, you’ll enjoy long-term protection from drafts, pests, or leaky windows.