Home Repairs: What Are The Best Caulk For Windows?


This article promises to give a detailed review of the best caulk for windows. But before that, let’s get some basic understanding of what caulking is.

Image by DIY Network

Many people may not be familiar with the term ‘caulking.’ To put it simply, it is a waterproof sealant. You may have seen many people using this substance in building work and repairs, especially for cracks on window surfaces.

Because there are many types of caulk with different purposes, choosing the suitable caulk for your window is certainly not an easy task. And you’ll find essential information about all of those matters in this article.

Without further ado, let’s begin.

Best Caulk For Windows Per Category

#1 Flex Shot B00HNDHEKG Thick Rubber Adhesive Sealant Caulk – Best Overall

The first product on our top list is the Flex Shot B00HNDHEKG Thick Rubber Adhesive Sealant Caulk. It has a lot of distinctive features, which makes it the best overall caulk.

With this splendid caulk, you can perform a perfect bead with undeniable ease. There will be virtually no running, no dripping, no mess at all. Even if you are a novice at caulking, it won’t be a problem with this product.

And you know what – the design makes the process of caulking hassle-free. A bulky caulking gun is unnecessary for this product. All you need to do is to push the trigger nozzle on the top of the caulk.

The caulk comes in four different colors, namely almond, black, clear, and white. These colors are very eye-pleasing, promising to make your windows look fantastic.

Because this product is the best overall, we have nothing to complain about. You can rest assured about the quality of this caulk.


  • Offering a perfect bead
  • Easy to use
  • Many color options


  • None

#2 GE Sealants & Adhesives B000M2UPAG Advanced Silicone Caulk – Best Efficiency

If you are looking for a caulk with excellent performance, this product is the perfect choice. The GE Sealants & Adhesives B000M2UPAG Advanced Silicone Caulk prides itself on its optimum efficiency.

The magic lies in this product’s 30-minute rain-ready formula. Specifically, the sealant it produces is 40% more flexible than the Class 25 counterpart. Also, its adhesion is five times stronger compared to that of the Silicone 1 sealant.

Another worth-mentioning feature is that the sealant won’t blemish your metal objects. Be it high-quality metal finishes like chrome, bronze, or nickel, they won’t get discolored whatsoever with this outstanding caulk.

We have extra good news for those on a tight budget. The price is affordable, so you can purchase the product without breaking the bank.

We do give this caulk a minus point, however. The tube doesn’t seem to be very well designed as some people find it quite challenging to get the sealant inside. You may need to squeeze the tube a bit harder in this case.


  • Highly effective
  • Discoloration-free
  • Budget-friendly


  • A little challenging to use

#3 GE Sealants & Adhesives B000BQSXSE Paintable Silicone Caulk – Best Versatility

The next candidate on our recommended list is the GE Sealants & Adhesives B000BQSXSE Paintable Silicone Caulk. What is unique about this product is its versatility.

Specifically, the caulk can work well virtually on any materials. These include metals, aluminum, brick, stucco, masonry, fiberglass, to name but a few. Even if it is a painted surface, it’ll be no problem.

Not only that, what we love about this caulk is its insignificant odor. Thanks to the neutral-cure formula, there won’t be any unpleasant smell when caulking.

This product is very easy on the wallet, too. You can purchase this high-quality caulk at an affordable price.

However, there is one thing you need to be aware of. If you accidentally got some of the sealant on your skin while caulking, it would be tough to get off. You can efficiently avoid this from happening with protective gloves and old trousers and long-sleeve tops.


  • Versatility
  • Unnoticeable odor
  • Affordable price


#4 Max Shield B07WFX445J All Weather Caulk – Best Flexibility

For those seeking a caulk with supreme flexibility, try Max Shield B07WFX445J All Weather Caulk. As written above, this caulk’s sealant is much more flexible compared to other competitors.

Judging by the ASTM C-920 standard specifications, the sealant this caulk produces can outclass its counterparts with over 800% stretch and 35% joint movement. Noticeably, the caulk can also seal up to three-inch gaps, adding to its flexibility.

This product is highly paint-ready, too. It only takes 45 minutes for the sealant to be ready for painting. This aspect is precisely what most painters desire.

Read more: How Long Does Caulk Take to Dry?

There are nine beautiful colors available for this caulk. Feel free to pick your favorite!

A friendly reminder is that the product’s sealant is not very weatherproof, regardless of its name. If it gets exposed to heavy rain in less than 24 hours since applied, it might melt and leave unwanted residue. 

Please pay extra attention to this and plan your repair according to the weather forecast.


  • Flexibility
  • Paint-ready in 45 minutes
  • Many colors available


  • Not very weatherproof

#5 Gorilla B01MQW8AEM 100% Silicone Clear Sealant Caulk – Best Utility

Are you planning to buy a caulk not just for windows but for other furniture as well? If so, take a look at the Gorilla B01MQW8AEM 100% Clear Sealant Caulk.

With 100% silicone, the product does an excellent job in sealing either gaps or cracks. Thus, it can work very well not just on windows but also on doors, kitchens, baths, gutters, autos, and marine plumbing. It is virtually applicable to both interiors and exteriors.

Also, the caulk can produce a durable sealant that is very waterproof. That is to say; exposure to water is no problem with this product, provided that it has dried for half an hour beforehand.

With this great caulk, you won’t get to see a single yellow stain or crack on your windows. Nor will you spot any disgusting mold and mildew.

However, the high price of this product may be a bit off-putting. But for all its outstanding features, it is a worthwhile investment.


  • Applicable on many furniture
  • Waterproof
  • No mold, mildew, crack


  • A little costly

Buying Guide

It is not a good idea to open your wallet and spend money on a product you know nothing about. In that case, doing some good research beforehand would be a wise choice. With that in mind, we are going to provide you some useful guidelines:


First off, you need to identify what you are going to caulk.

  • Exterior windows: In this situation, the caulk must be highly durable and resistant to external factors. These include harsh ultraviolet rays, water exposure, and temperature changes.

We highly recommend the Gorilla B01MQW8AEM Caulk. Although as we reviewed above, you can use it for both interiors and exteriors. 

  • Interior windows: These objects require a caulk that is free of toxic fumes. Also, the caulk must be able to hold the paint well.

The GE Sealants & Adhesives B000BQSXSE Caulk is a perfect choice. It produces a very low odor, so it is advisable to use it on interior windows.

  • Humid rooms: The caulk for damp rooms like bathrooms has some special requirements. It must be waterproof and resistant to mold and mildew.
  • Masonry siding: In this situation, you should choose a suitable caulk to work well with the masonry surface. Otherwise, the process of caulking will be a whole disaster.


After you have already made up your mind about what you want to caulk, you should choose the right type of caulk for optimal results.

  • Latex Caulk: This type of caulk usually contains acrylic. Speaking of which, you might spot acrylic caulk, which bears some similarities with the latex counterpart in terms of function.

Specifically, latex caulk is water-based, meaning that it is free of volatile chemicals. Thus, this is the best caulk for windows interior. While some caulks are not paintable, you can paint as you wish with latex caulks. 

However, these caulks are not susceptible to high moisture and fluctuating temperatures. It is preferable to use latex caulk on interior windows rather than exterior counterparts.

  • Siliconized Latex Caulk: Caulks of this type do not differ much from the acrylic latex ones, except that they contain a variety of silicone called silane. Thanks to the added substance, siliconized latex caulk offers better adherence.

In general, these caulks have almost the same features as the acrylic latex one, except that it boasts more durability and resilience to elements. They are the best caulk for windows exterior.

  • Silicone caulks: These caulks are made of silicone elastomers, making them rubbery when curing. Silicone caulks can withstand temperature changes and water exposure. They are resistant to mildew as well.
  • Polyurethane: Caulks made of polyurethane can stick to many materials such as plastic and wood. They are very resistant and not prone to corrosion. But bear in mind that this caulk can not withstand sunlight.


Q1: Should You Caulk Inside Of Windows?

A: Yes. For optimal performance, we recommend caulking both the interior and exterior of the windows. By doing this, you can seal any air leaks.

Q2: Where Should You Not Caulk Around Windows?

A: People tend to think that the more they caulk, the better the result will turn out. However, there are some particular areas that you should not caulk under any circumstances: 

  • Weep hole: Vinyl windows usually have a tiny hole at the bottom, where moisture evaporates. If you accidentally caulk this area, the moisture will build up in your house. The ultimate result is mold and mildew.
  • Above the window frame: This area is the drip edge. Its primary function is to get rid of water from your windows and siding. Without it, the accumulated moisture will remain in your house.
  • The area where the window meets the siding: Only when there is a flush fit in this area should you apply the caulk. Otherwise, it would be counter-productive. 

The area needs a kind of caulking that can withstand the elements. The perfect choice in this situation is the weatherproof silicone caulk.

  • Moveable parts: Needless to say, you should not caulk these parts in any case. Please be extra careful when you caulk windows with movable parts.
  • The area where the window trim joins the siding: This area already has proper insulation, so there is no need for you to caulk. It would be harmful if you caulked this area as it will deliver even more moisture into your house.

Q3: When Should You Caulk Windows?

A: Timing is essential to get the best results. Specifically, 45°F temperature is the ideal time. If you don’t want cracks to swell from moisture, you should apply the caulk in dry weather and low humidity. 

Q4: Do I Have To Remove The Old Caulk Before Caulking?

A: No. It is possible to apply a new bead of caulk, as long as it is wide enough to cover the old caulk. Remember to use alcohol to clean the old bead’s surface before applying, though.

Image by Doityourself.com

However, applying a new caulk over an old one is not always fruitful. You should ensure that the new caulk sticks well on the old one. A caulking gun can be of great help for you. 

Read more: The Best Removable Caulk That Returns Your Walls To Its Pristine Look

Q5: Is Caulk The Same As Silicone?

A: No. They differ significantly in many terms.

Caulks’ primary function is to seal construction cracks. It can dry more quickly than silicone. Also, caulks are not only weatherproof but also paintable with acrylic paint. Usually, these products are the best ideal to seal cracks in walls and ceilings.

Meanwhile, it is advisable to bind metals, glass, and plastic together with silicone. Silicone is usable even if it is in a damp room. 

Unlike caulks, silicone can work well in areas that are prone to expansion and contraction. However, most silicone is not paintable. Generally, you can apply silicone to seal joints between tiles, bathroom fittings, and sinks.

Q6: What Happens If You Caulk Over The Old Caulk?

A: It depends on the condition of the existing caulk. It would be futile if the old caulk is hardening and prone to coming off. As the existing caulk continues to pull away, it will also take off the new caulk in the process. You’ll get to see a thick caulk line that ruins the beauty of your windows. 

Q7: Do You Caulk Windows Before Or After Painting?

A: It would be unfair to claim which method is better than the other, as both have some drawbacks.

Caulking windows before painting has some disadvantages. Because exterior windows get exposed to many external factors, they will quickly attract dirt. So if you do the painting after caulking the window, there will be unwanted specks of dirt on the surface.

Then you have to remove both the caulk and the paint to get rid of the dirt. The whole process suddenly becomes a hassle.

On the other hand, painting the windows in advance makes it easy to maintain the windows’ pristine condition. But this method will make your windows look untidy due to the residue on the surface.


So, what is on your mind now? We can confidently say that this article has provided you with sufficient information about the best caulk for windows.

If you are still wavering between options, you can go for our top pick – the Flex Shot B00HNDHEKG Thick Rubber Adhesive Sealant Caulk.

Finally, thank you for reading! We hope you will choose the right kind of caulk to improve your windows’ appearance!