Flex Shot vs. Silicone Caulk – (Which Is Better)

Silicone caulk is a convenient product used to fill in gaps in windows, doors, bathrooms, kitchens, and even concrete. With new products like Flex Shot on the market, how do you know which is better?

Flex Shot vs. Silicone Caulk

Silicone caulk is a waterproof, weather-resistant material used to seal wood, plastic, metal, granite, and more. Silicone caulk often requires the use of a caulking gun. Flex shot is made from liquid rubber and works on the same surfaces as silicone caulk but does not require a caulking gun.

Before starting your next project, you may need to decide whether Flex Shot or silicone caulk is suitable for your needs. This article will give you the pros and cons of both so you can consider your needs and make the best decision. Let’s get to it! 

Flex Shot

Flex Shot was created by the brand Flex Seal. It comes in a spray can and can be used in many ways: weatherizing a boat, sealing the base of your toilet, and more. With a higher price point than traditional silicone caulk, the pros and cons listed below will help you decide if the price tag is worth it:

Pros of Flex Shot

  • There is no need for a caulking gun, so it may be easier for those with less experience.
  • Flex shot is waterproof and weatherproof. 
  • It works on almost any surface that is free from oil or grease.

Cons of Flex Shot

  • Flex shot is more expensive than silicone caulk.
  • It only comes in four colors: white, clear, almond, and black.
  • It doesn’t have many differences when compared to regular caulk.

Silicone Caulk

You can use silicone caulk to fill in and seal gaps. One popular use for silicone caulk is in the bathroom. If your toilet rocks when you sit on it, check out my article to learn how to use caulk to fix it. 

Pros of Silicone Caulk

  • Silicone caulk is affordable and available for even cheaper per unit if you buy it in bulk.
  • You can use it on multiple surfaces, including metal, plastic, and wood.
  • Heat, cold, and water will not break the seal or cause melting, cracking, or other defects. 

Cons of Silicone Caulk

  • Silicone caulk typically requires the use of a caulking gun.

If you’re not particularly fussed about using a caulking gun, this won’t be a big problem for you. Traditional caulk is relatively simple to use and is typically more popular than other products.

Is Flex Shot Better Than Silicone Caulk?

sealing finished ceramic tiles

Regardless of your skill level, silicone caulk is undoubtedly the more affordable option of the two.

The most significant difference between caulk and Flex Shot is the need for a caulking gun. However, if you opt for traditional silicone caulk, options are available that don’t require a caulking gun, like the DAP Kwik Seal Adhesive Caulk from Amazon.com. This product doesn’t require a caulking gun, uses waterproof materials, and is suitable for multiple surfaces.

If you’ve opted for traditional silicone caulk that requires a gun, this Bates Choice Caulking Gun from Amazon.com is an affordable option. You’ll only need to buy the caulking gun once, as you can use it countless times. Additionally, it includes a seal puncture needle as well as a convenient hole in the handle that can cut the tip off of your new tube of silicone caulk.

Caulk vs. Flex Seal

Flex seal is not always a good substitute for silicone caulk, but you can use it on many of the same surfaces as silicone caulk. While Flex Seal seems easier to use because you don’t need a caulking gun, its aerosol can makes the application less controlled.

The following section will detail the pros and cons of flex seal so that you can compare it to silicone caulk and decide if it is suitable for your next project.

Flex Seal

You may know about Flex Seal because of the entertaining commercials featuring the company’s iconic spokesperson Phil Swift. He can often be found paddling out to the middle of a lake and sealing the leaks in his boat with Flex Seal and Flex Seal Patches. So is Flex Seal worth the hype?

Pros of Flex Seal

  • Flex Seal works on multiple surfaces.
  • It is weatherproof and waterproof.
  • It comes in many colors, from clear to black and even orange.

Cons of Flex Seal

  • Flex seal comes in an aerosol can, so control over where the product is applied may be limited.
  • Flex Seal may be better suited for larger areas like boats rather than small, concentrated projects like sealing the base of a toilet. 

Is Flex Seal Better Than Silicone Caulk?

Ultimately, it would be beneficial to keep both on hand because they have different uses. Silicone caulk may be a better choice if you’re looking to:

  • Seal a wobbly toilet.
  • Waterproof the seams of a shower.
  • Seal windows or a drafty door.

Smaller projects typically call for silicone caulk.

That said, Flex Seal is great for larger projects, such as: 

  • Winterizing your RV. 
  • Waterproofing a leaky boat. 
  • Protecting large areas from leaks or moisture buildup.

The spraying application allows you to cover a larger surface area in less time than with traditional caulk.

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Can You Use Peel-and-Stick Caulk Instead of Silicone Caulk?

Aside from Flex Shot, Flex Seal, and silicone caulk, there is a lesser-known option called peel-and-stick caulk, also known as caulk tape. It comes in a roll or a pack by the yard and is typically used for simple repairs in your bathroom, kitchen, windows, or doors. 

caulk tape

This Solikdm Bath and Kitchen Caulk Tape from Amazon.com comes in a 3.2-meter (10.49 ft) roll and can be applied in only a few minutes with a hair dryer for heat.

Pros of Peel-and-Stick Caulk

  • Caulk tape doesn’t require a gun.
  • You can finish your project in record time with no mess.
  • Its cost is similar to or even more affordable than other sealant options.

Cons of Peel-and-Stick Caulk

  • Its applications are limited to straight lines and slight curves.
  • Caulk tape might not be as effective or long-lasting as traditional caulk.
  • Caulk tape is typically not good for larger projects.

While there are a few disadvantages of using peel-and-stick caulk, the easy application makes it popular among home DIY-ers for smaller projects.


When deciding between silicone caulk, Flex Shot, and Flex Seal, consider your skill level, the area you’ll be sealing, and the time restraints you have to complete the project. While all three are designed to be waterproof and weatherproof, the application, cost, and available color options differ. 

Sealing areas like windows, doors, and bathrooms is essential to the upkeep of your home, so you’re on the right track no matter what you choose.