7 Best Caulk for Sealing Exterior Windows Tested 2025

I remember the first time I tackled sealing my own exterior windows; it felt like a daunting task. The drafts, the energy loss, and the potential for water damage were all on my mind. After a fair bit of research and some hands-on trials, I realized just how crucial choosing the best caulk for sealing exterior windows really is. A good caulk doesn’t just fill a gap; it creates a durable, weather-tight barrier that protects your home for years. This guide pulls together my findings, focusing on what genuinely works to help you pick the right sealant for your needs.

IMAGE	PRODUCT NAME	AMAZON LINK
	GE Advanced Silicone Caulk for Window & Door, Clear, 2.8…	View on Amazon
	Flex Caulk, Waterproof & Weatherproof Hybrid Polymer…	View on Amazon
	GE Advanced Silicone Caulk for Window & Door, White, 10…	View on Amazon
	Gorilla Waterproof Caulk & Seal Silicone Sealant, 10oz…	View on Amazon
	GE Supreme Paintable Silicone Caulk for Window & Door,…	View on Amazon
	GE Supreme Silicone Caulk for Window & Door, Clear, 10…	View on Amazon
	Dap 18354 Seal ‘N Peel Removable Caulk, 10.1-Ounce	View on Amazon

1. GE Advanced Silicone Caulk for Window & Door, Clear, 2.8…

This GE Advanced Silicone caulk is a true workhorse, offering robust protection for your window and door perimeters. Its 100% silicone formula is designed to deliver exceptional waterproofing and weather resistance, ensuring that rain, snow, and moisture stay exactly where they belong – outside. I’ve found it creates a strong, flexible seal that moves with your home without cracking, making it a reliable choice for long-term durability against the elements.

Key features that stand out:
– 100% Waterproof and Weatherproof: Provides a reliable seal against water damage in harsh weather.
– 10-Year Product Protection: Resistant to stain-causing mold and mildew growth.
– Permanently Flexible with Strong Adhesion: Offers 40% more flexibility and 5X stronger adhesion than Silicone 1 sealants.
– Durable: Rain-ready in 30 minutes, resistant to shrinking and cracking.
– Compatible with Most Materials: Adheres well to metals, woods, brick, stone, glass, and more.

Pros:
– Exceptional waterproofing and weather resistance.
– Great flexibility to prevent cracking.
– Quick rain readiness.
– Strong adhesion to various surfaces.
– Clear finish blends seamlessly.

Cons:
– As a silicone product, it’s generally not paintable.

Best for: Homeowners seeking a clear, highly durable, and flexible seal for long-term exterior window protection where paintability isn’t a concern.

Expert Opinion: This is a solid, go-to silicone caulk. Its quick rain-ready time and strong, flexible bond make it excellent for outdoor applications where you need a clear, long-lasting, and weather-proof seal that won’t give up.

2. Flex Caulk, Waterproof & Weatherproof Hybrid Polymer…

Flex Caulk stands out for its incredible ease of use and versatility, making it a great option if you’re not a fan of traditional caulk guns or just want something simpler. This advanced hybrid polymer formulation creates a powerful, waterproof, and weatherproof barrier that adheres to almost any surface, even wet ones. I appreciate that it won’t shrink or crack, providing a durable and reliable seal that you can even paint over, which is a big plus for matching your home’s aesthetic.

Key features that stand out:
– So easy to use: No caulk gun needed with its adjustable trigger flow nozzle.
– Advanced hybrid polymer formulation: Seals out water, air, and moisture effectively.
– Adheres to virtually any surface, wet or dry: Highly versatile for various applications.
– Won’t shrink, crack, or become brittle: Ensures a long-lasting and durable seal.
– Fully paintable: Allows for a seamless match with your existing paint.

Pros:
– Extremely user-friendly; no caulk gun required.
– Excellent adhesion to a wide range of materials, even wet.
– Resistant to shrinking, cracking, and brittleness.
– Paintable, offering greater aesthetic flexibility.
– UV and chemical resistant for enhanced durability.

Cons:
– Smaller cartridge size might require multiple units for larger projects.

Best for: DIY enthusiasts looking for an easy-to-apply, paintable, and highly versatile caulk that works on almost any surface, wet or dry.

Expert Opinion: This is an excellent choice for convenience and adaptability. Its hybrid polymer makes it a strong contender for its paintability and ability to adhere to challenging surfaces, perfect for quick fixes or areas where you want to match existing paint.

3. GE Advanced Silicone Caulk for Window & Door, White, 10…

Much like its clear counterpart, the GE Advanced Silicone Caulk in white offers the same high level of performance but with a crisp, clean finish. This 100% silicone formula is a fortress against water damage, making it an ideal best caulk for sealing exterior windows where you need a strong, white line to define or complement your trim. It boasts impressive flexibility and adhesion, ensuring your seal remains intact through all sorts of temperature shifts and weather conditions, backed by a significant mold-free product protection.

Key features that stand out:
– 100% Waterproof and Weatherproof: Offers superior protection against water damage.
– 10-Year Mold-Free Product Protection: Cured sealant resists stain-causing mold and mildew.
– Permanently Flexible with Strong Adhesion: Provides 40% more flexibility and 5X stronger adhesion than Silicone 1.
– Durable: Rain-ready in 30 minutes, resistant to shrinking and cracking.
– Compatible with Most Materials: Adheres to metals, woods, brick, glass, and more.

Pros:
– Superior waterproofing and weather resistance.
– Excellent mold and mildew resistance for a clean look.
– High flexibility and strong adhesion.
– Quick rain readiness.
– Bright white finish for a clean aesthetic.

Cons:
– Like most silicones, it’s not typically paintable.

Best for: Projects requiring a durable, white, waterproof seal around exterior windows where mold resistance and long-term flexibility are key, and painting isn’t necessary.

Expert Opinion: This white silicone is a reliable staple for exterior window sealing. Its rapid rain-readiness is fantastic, and the 10-year mold protection is a huge benefit for maintaining a tidy, effective seal in exposed areas.

4. Gorilla Waterproof Caulk & Seal Silicone Sealant, 10oz…

Gorilla Waterproof Caulk & Seal brings the brand’s renowned toughness to window sealing. This 100% silicone sealant is designed for both indoor and outdoor use, creating a watertight barrier that seals out air, water, and moisture. What truly impresses me is its speedy water exposure readiness – you can expose it to water in just 30 minutes! It’s built to last, resisting mold and mildew, and you won’t have to worry about it yellowing, shrinking, or cracking over time, making it a very robust option for your exterior windows.

Key features that stand out:
– Speed meets strength: Rain-ready in as little as 30 minutes.
– All-purpose: Suitable for both indoor and outdoor applications.
– Waterproof sealant: Forms a 100% silicone seal (as cured) against air, water, and moisture.
– Gorilla tough: Mold & mildew resistant, won’t yellow, shrink, or crack.

Pros:
– Extremely fast water exposure readiness.
– Highly durable and resistant to common sealant failures.
– Excellent mold and mildew resistance.
– Versatile for multiple applications.
– Provides a strong, waterproof seal.

Cons:
– As a silicone sealant, it’s generally not paint-friendly.

Best for: Anyone needing a tough, fast-setting, and exceptionally durable waterproof seal for exterior windows, especially in areas prone to quick weather changes.

Expert Opinion: You can’t go wrong with Gorilla’s reputation for strength. The 30-minute rain-ready time is a huge advantage, letting you finish up without constantly checking the weather report. It’s a truly reliable option for sealing windows.

5. GE Supreme Paintable Silicone Caulk for Window & Door,…

This GE Supreme Paintable Silicone Caulk is a standout for those who need the durability of silicone but also desire a seamless aesthetic. It offers the 100% waterproof and weatherproof protection you’d expect from GE silicone, along with superior flexibility and adhesion (7X stronger than their Silicone 1). The real game-changer here is its paintability, allowing you to perfectly match your home’s exterior color without compromising on the robust, shrink- and crack-proof performance necessary for exterior windows.

Key features that stand out:
– 100% Waterproof and Weatherproof: Reliable protection from water damage and weather exposure.
– Permanently Flexible with Strong Adhesion: 40% more flexibility and 7X stronger adhesion than Silicone 1.
– Shrink- and Crack-Proof: Withstands extreme temperature fluctuations.
– Paintable: Easily fits in with your home’s surroundings.
– Compatible with Most Materials: Adheres to metals, woods, brick, stone, glass, and more.

Pros:
– Offers the best of both worlds: silicone durability and paintability.
– Superior flexibility and adhesion for long-lasting seals.
– Excellent resistance to shrinking and cracking.
– Strong waterproof and weatherproof properties.
– Wide material compatibility.

Cons:
– May not be as readily available in all color options as some non-paintable silicones.

Best for: Homeowners who need the ultimate performance of a silicone sealant for exterior windows but also require the ability to paint over it for a finished look.

Expert Opinion: This is a fantastic innovation, blending the robust performance of silicone with the aesthetic flexibility of paintability. It’s my top pick when you absolutely need a durable, waterproof seal that also needs to blend in perfectly with your paint scheme.

6. GE Supreme Silicone Caulk for Window & Door, Clear, 10…

The GE Supreme Silicone Caulk in clear takes reliability to the next level, offering lifetime product protection against mold and mildew alongside its 100% waterproof capabilities. This premium silicone formula delivers exceptional flexibility (40% more than Class 25 sealants) and significantly stronger adhesion (7X stronger than Silicone 1), ensuring your exterior window seals remain pristine and effective for the long haul. It’s engineered to be shrink- and crack-proof, making it an excellent choice for areas exposed to constant temperature fluctuations.

Key features that stand out:
– 100% Waterproof and Weatherproof: Top-tier protection from water damage and weather exposure.
– Lifetime Product Protection: Cured sealant resists stain-causing mold and mildew growth.
– Permanently Flexible with Strong Adhesion: Offers 40% more flexibility and 7X stronger adhesion than Silicone 1.
– Shrink and Crack Proof: Withstands extreme expansion and contraction.
– Compatible with Most Materials: Adheres to metals, woods, brick, stone, glass, and more.

Pros:
– Unmatched lifetime mold and mildew protection.
– Superior flexibility and adhesion for extreme durability.
– Completely shrink and crack proof.
– Excellent waterproofing and weatherproofing.
– Clear finish for invisible sealing.

Cons:
– Like other 100% silicones, it cannot be painted over.

Best for: Those who prioritize maximum, long-term durability, superior flexibility, and lifetime mold protection for their exterior window seals, especially where a clear, unpainted finish is desired.

Expert Opinion: This is the pinnacle of clear silicone caulk. The lifetime mold protection combined with extreme flexibility and adhesion makes it an incredibly robust and low-maintenance choice for sealing exterior windows where you want to set it and forget it.

7. Dap 18354 Seal ‘N Peel Removable Caulk, 10.1-Ounce

The Dap Seal ‘N Peel Removable Caulk offers a unique solution for temporary or seasonal sealing needs around exterior windows. Unlike permanent caulks, this synthetic rubber formula applies like a regular caulk but can be easily peeled away when it’s no longer needed, without damaging painted surfaces. It forms a watertight, weatherproof seal that helps save energy, keeping your home warmer in winter and cooler in summer. While not for permanent installation, its removability makes it incredibly versatile for specific situations.

Key features that stand out:
– Temporary, removable seal: Easily peels away without caulk remover.
– Synthetic rubber formula: Applies like caulk, provides watertight and weatherproof seal.
– Multi-season use: Helps save energy by sealing drafts.
– Won’t damage painted surfaces: Safe for temporary application on finished areas.
– Interior/exterior use: Versatile for various temporary sealing needs.

Pros:
– Easily removable without leaving residue or damage.
– Effective watertight and weatherproof seal for temporary use.
– Dries tack-free quickly.
– Great for seasonal energy efficiency.
– Safe for use on painted surfaces.

Cons:
– Not suitable for permanent exterior window sealing projects.

Best for: Homeowners needing a temporary or seasonal seal for exterior windows, such as for winterizing, air conditioning units, or rental properties, where easy removal is a must.

Expert Opinion: This product serves a very specific niche. If you’re looking for a non-permanent solution for your exterior windows, say for draft control during winter, it’s fantastic. Just remember it’s not a substitute for a long-term, durable caulk for structural sealing.

Helpful Comparison Short Insights

When choosing the best caulk for sealing exterior windows, you’ll notice a few key differences. GE Advanced Silicone (both clear and white) and Gorilla Waterproof Caulk & Seal are excellent choices for permanent, robust waterproofing with quick rain-ready times, but remember, they are not paintable. If paintability is crucial for your exterior window project, the GE Supreme Paintable Silicone is a standout, combining silicone’s strength with aesthetic flexibility. For ultimate, “set it and forget it” durability, especially against mold and mildew, the GE Supreme Silicone Caulk offers lifetime protection and superior flexibility. The Flex Caulk is a fantastic hybrid option if you want ease of use without a caulk gun and the ability to paint over it. Finally, the Dap Seal ‘N Peel is in a league of its own for temporary, removable sealing, perfect for seasonal adjustments rather than long-term structural integrity.

Final Verdict: Choosing Your Window Sealing Champion

Deciding on the best caulk for sealing exterior windows really comes down to your specific needs and priorities.

• For Unrivaled Durability & Lifelong Protection: If you want the absolute toughest, most flexible, and mold-resistant seal that will last for decades without needing paint, the GE Supreme Silicone Caulk (Clear) is your undisputed champion. It’s top-tier performance.

• For Durability with a Perfect Paint Match: When you need the superior protection of silicone but absolutely must paint over it to blend with your home’s exterior, the GE Supreme Paintable Silicone Caulk is the clear winner. It’s the best of both worlds.

• For Everyday Robust Sealing with Quick Set Time: If you’re looking for a reliable, strong, and fast-acting waterproof seal that stands up to the elements without needing paint, the Gorilla Waterproof Caulk & Seal Silicone Sealant and the GE Advanced Silicone Caulk (in both clear and white) are excellent, dependable choices.

• For Ultimate Ease and Versatility (Paintable): If you prioritize convenience and a caulk that adheres to almost anything (even wet) and is paintable without needing a caulk gun, the Flex Caulk is an outstanding, user-friendly option.

• For Temporary or Seasonal Sealing: When you need a seal that’s effective but also removable without damage, the Dap Seal ‘N Peel Removable Caulk is the unique solution for short-term needs like winterizing.

Ultimately, assess your project: Do you need a permanent, paintable, or temporary seal? How crucial is quick rain readiness or mold resistance? Your answers will guide you to the perfect caulk for your exterior windows.

FAQ Section

Q1: What is the best caulk for sealing exterior windows that are exposed to harsh weather?
A1: For harsh weather, 100% silicone caulks like the GE Advanced Silicone Caulk or Gorilla Waterproof Caulk & Seal Silicone Sealant are highly recommended. They offer superior waterproofing, flexibility, and resistance to extreme temperatures, making them ideal for exterior windows.

Q2: Can I paint over all types of caulk used for exterior windows?
A2: No, not all caulks are paintable. Traditional 100% silicone caulks are generally not paintable. If you need to paint your caulk to match your home’s exterior, look for products specifically labeled as “paintable silicone” or hybrid polymer caulks, such as the GE Supreme Paintable Silicone Caulk or Flex Caulk.

Q3: How long does exterior window caulk typically last?
A3: The lifespan of exterior window caulk varies significantly by type and quality. High-quality silicone caulks, like the GE Supreme Silicone or Advanced Silicone, can last 10 years or more, with some offering lifetime product protection against mold and mildew. Acrylic latex caulks generally have a shorter lifespan.

Q4: What’s the main difference between silicone and hybrid polymer caulk for sealing exterior windows?
A4: Silicone caulk offers excellent flexibility, waterproofing, and durability against UV rays and temperature extremes, but it’s typically not paintable. Hybrid polymer caulks (like Flex Caulk) combine properties of silicone and polyurethane, offering good flexibility, strong adhesion, and paintability, making them a versatile choice for exterior windows.

Q5: How do I prepare my exterior windows before applying caulk?
A5: Proper preparation is crucial for a lasting seal. First, remove all old caulk using a caulk removal tool or utility knife. Clean the surface thoroughly with a wire brush or scraper, then wash with soap and water, and allow it to dry completely. Any loose debris, dirt, or moisture will prevent the new caulk from adhering properly, even the best caulk for sealing exterior windows.

Q6: Is it necessary to use a caulk gun for all exterior window sealing projects?
A6: Most standard caulk tubes require a caulk gun for application. However, some innovative products like Flex Caulk come in a specialized dispenser with an adjustable trigger, eliminating the need for a separate caulk gun, which can be much more convenient for some users.

Q7: Can I use removable caulk for permanent exterior window sealing?
A7: No, products like Dap Seal ‘N Peel Removable Caulk are designed for temporary or seasonal sealing. While they provide an effective seal, they lack the long-term durability, flexibility, and strong adhesion required for permanent exterior window sealing, which is essential for protecting your home over many years.